Update history to reflect merge of #492 [ci skip]

Merge pull request 492

.github/workflows/ci.yml

@@ -0,0 +1,103 @@
+name: Continuous Integration
+
+on:
+  push:
+    branches:
+    - master
+  pull_request:
+    branches:
+    - master
+
+jobs:
+  j4:
+    if: "!contains(github.event.commits[0].message, '[ci skip]')"
+    name: "Jekyll ${{ matrix.jekyll_version }} (Ruby ${{ matrix.ruby_version }})"
+    runs-on: 'ubuntu-latest'
+    env:
+      JEKYLL_VERSION: ${{ matrix.jekyll_version }}
+    strategy:
+      fail-fast: false
+      matrix:
+        ruby_version:
+        - 2.5
+        - 2.7
+        - 3.1
+        jekyll_version:
+        - "~> 4.0"
+    steps:
+      - uses: actions/checkout@v2
+        with:
+          fetch-depth: 5
+      - name: "Set up Ruby ${{ matrix.ruby_version }}"
+        uses: ruby/setup-ruby@v1
+        with:
+          ruby-version: ${{ matrix.ruby_version }}
+          bundler-cache: true
+      - name: Execute tests
+        run:  bundle exec rspec
+  j3:
+    if: "!contains(github.event.commits[0].message, '[ci skip]')"
+    name: "Jekyll ${{ matrix.jekyll_version }} (Ruby ${{ matrix.ruby_version }})"
+    runs-on: 'ubuntu-latest'
+    env:
+      JEKYLL_VERSION: ${{ matrix.jekyll_version }}
+    strategy:
+      fail-fast: false
+      matrix:
+        ruby_version:
+        - 2.5
+        jekyll_version:
+        - "~> 3.9"
+    steps:
+      - uses: actions/checkout@v2
+        with:
+          fetch-depth: 5
+      - name: "Set up Ruby ${{ matrix.ruby_version }}"
+        uses: ruby/setup-ruby@v1
+        with:
+          ruby-version: ${{ matrix.ruby_version }}
+          bundler-cache: true
+      - name: Execute tests
+        run:  bundle exec rspec
+
+  style_check:
+    if: "!contains(github.event.commits[0].message, '[ci skip]')"
+    name: "Code Style Check (Ruby ${{ matrix.ruby_version }})"
+    runs-on: 'ubuntu-latest'
+    strategy:
+      fail-fast: false
+      matrix:
+        ruby_version:
+        - 2.5
+    steps:
+      - uses: actions/checkout@v2
+        with:
+          fetch-depth: 5
+      - name: "Set up Ruby ${{ matrix.ruby_version }}"
+        uses: ruby/setup-ruby@v1
+        with:
+          ruby-version: ${{ matrix.ruby_version }}
+          bundler-cache: true
+      - name: Check Style Offenses
+        run:  bundle exec rubocop -S -D
+
+  gem_build:
+    if: "!contains(github.event.commits[0].message, '[ci skip]')"
+    name: "Test Gem build (Ruby ${{ matrix.ruby_version }})"
+    runs-on: 'ubuntu-latest'
+    strategy:
+      fail-fast: false
+      matrix:
+        ruby_version:
+        - 2.5
+    steps:
+      - uses: actions/checkout@v2
+        with:
+          fetch-depth: 5
+      - name: "Set up Ruby ${{ matrix.ruby_version }}"
+        uses: ruby/setup-ruby@v1
+        with:
+          ruby-version: ${{ matrix.ruby_version }}
+          bundler-cache: true
+      - name: Test Gem build
+        run:  bundle exec gem build jekyll-seo-tag.gemspec

.github/workflows/release.yml

@@ -0,0 +1,33 @@
+name: Release Gem
+
+on:
+  push:
+    branches:
+      - master
+    paths:
+      - "lib/**/version.rb"
+
+jobs:
+  release:
+    if: "github.repository_owner == 'jekyll'"
+    name: "Release Gem (Ruby ${{ matrix.ruby_version }})"
+    runs-on: "ubuntu-latest"
+    strategy:
+      fail-fast: true
+      matrix:
+        ruby_version:
+          - 2.7
+    steps:
+      - name: Checkout Repository
+        uses: actions/checkout@v2
+      - name: "Set up Ruby ${{ matrix.ruby_version }}"
+        uses: ruby/setup-ruby@v1
+        with:
+          ruby-version: ${{ matrix.ruby_version }}
+          bundler-cache: true
+      - name: Build and Publish Gem
+        uses: ashmaroli/release-gem@dist
+        with:
+          gemspec_name: jekyll-seo-tag
+        env:
+          GEM_HOST_API_KEY: ${{ secrets.RUBYGEMS_GEM_PUSH_API_KEY }}

.github/workflows/scripts/memprof

@@ -0,0 +1,4 @@
+#!/usr/bin/env bash
+
+bundle exec ruby jekyll-seo-tag/.github/workflows/scripts/memprof.rb sandbox
+exit 0

.github/workflows/scripts/memprof.rb

@@ -0,0 +1,14 @@
+# frozen_string_literal: true
+
+require 'jekyll'
+require 'memory_profiler'
+
+MemoryProfiler.report(allow_files: 'lib/jekyll-seo-tag') do
+  Jekyll::PluginManager.require_from_bundler
+  Jekyll::Commands::Build.process({
+    "source"             => File.expand_path(ARGV[0]),
+    "destination"        => File.expand_path("#{ARGV[0]}/_site"),
+    "disable_disk_cache" => true,
+  })
+  puts ''
+end.pretty_print(scale_bytes: true, normalize_paths: true)

.github/workflows/third-party.yml

@@ -0,0 +1,63 @@
+name: Third-Party Repository Profiling
+
+on:
+  push:
+    branches:
+      - master
+  pull_request:
+    branches:
+      - master
+jobs:
+  build_n_profile:
+    name: "Third-Party Repo Profile (Jekyll ${{ matrix.jekyll_version }}, Ruby ${{ matrix.ruby_version }})"
+    runs-on: "ubuntu-latest"
+    strategy:
+      fail-fast: false
+      matrix:
+        ruby_version:
+          - 2.7
+        jekyll_version:
+          - "~> 4.0"
+          - "~> 3.9"
+    env:
+      BUNDLE_GEMFILE: "sandbox/Gemfile"
+      BUNDLE_PATH: "vendor/bundle"
+      BUNDLE_JOBS: 4
+      BUNDLE_RETRY: 3
+      JEKYLL_VERSION: ${{ matrix.jekyll_version }}
+    steps:
+    - name: Checkout Jekyll SEO Tag
+      uses: actions/checkout@v2
+      with:
+        fetch-depth: 5
+        path: jekyll-seo-tag
+    - name: Checkout Third-Party Repository (WITHOUT SEO Tag)
+      uses: actions/checkout@v2
+      with:
+        repository: ashmaroli/tomjoht.github.io
+        ref: "no-seo-tag"
+        path: alpha-sandbox
+    - name: Checkout Same Third-Party Repository (WITH SEO Tag)
+      uses: actions/checkout@v2
+      with:
+        repository: ashmaroli/tomjoht.github.io
+        ref: "seo-tag"
+        path: sandbox
+    - name: "Set up Ruby ${{ matrix.ruby_version }}"
+      uses: ruby/setup-ruby@v1
+      with:
+        ruby-version: ${{ matrix.ruby_version }}
+        bundler-cache: true
+    - name: Run Jekyll Build (WITHOUT SEO Tag) 3 times
+      run: |
+        bundle exec jekyll build -s alpha-sandbox -d alpha-sandbox/_site --trace
+        bundle exec jekyll build -s alpha-sandbox -d alpha-sandbox/_site --trace
+        bundle exec jekyll build -s alpha-sandbox -d alpha-sandbox/_site --trace
+    - name: Run Jekyll Build (WITH SEO Tag) 3 times
+      run: |
+        bundle exec jekyll build -s sandbox -d sandbox/_site --trace
+        bundle exec jekyll build -s sandbox -d sandbox/_site --trace
+        bundle exec jekyll build -s sandbox -d sandbox/_site --trace
+    - name: Memory Analysis of Jekyll Build (WITH SEO Tag)
+      run: bash jekyll-seo-tag/.github/workflows/scripts/memprof
+      if: "!contains(matrix.jekyll_version, '3.')"

.gitignore

@@ -1,11 +1,9 @@
-/.bundle/
-/.yardoc
-/Gemfile.lock
-/_yardoc/
-/coverage/
-/doc/
-/pkg/
-/spec/reports/
-/tmp/
-/bin/
 *.gem
+.bundle
+.yardoc
+Gemfile.lock
+pkg
+spec/reports/
+spec/fixtures/.jekyll-cache
+tmp/
+vendor/bundle

.rubocop.yml

@@ -1,25 +1,42 @@
-inherit_gem:
-  jekyll: .rubocop.yml
+inherit_from: .rubocop_todo.yml
 
-Metrics/LineLength:
+require: rubocop-jekyll
+inherit_gem:
+  rubocop-jekyll: .rubocop.yml
+
+AllCops:
+  TargetRubyVersion: 2.5
+  SuggestExtensions: false
+  Exclude:
+    - vendor/**/*
+
+Layout/LineEndStringConcatenationIndentation:
+  Enabled: true
+Layout/LineLength:
   Exclude:
     - spec/**/*
     - jekyll-seo-tag.gemspec
 
+Lint/EmptyInPattern:
+  Enabled: false
+
 Metrics/BlockLength:
   Exclude:
     - spec/**/*
 
-Style/Documentation:
+Naming/InclusiveLanguage:
   Enabled: false
 
-Style/FileName:
+Performance/MapCompact:
+  Enabled: true
+Performance/RedundantEqualityComparisonBlock:
+  Enabled: true
+Performance/RedundantSplitRegexpArgument:
+  Enabled: true
+
+Style/InPatternThen:
   Enabled: false
-
-Style/IndentHeredoc:
-  Exclude:
-    - spec/**/*
-
-AllCops:
-  Exclude:
-    - vendor/**/*
+Style/MultilineInPatternThen:
+  Enabled: false
+Style/QuotedSymbols:
+  Enabled: true

.rubocop_todo.yml

@@ -0,0 +1,46 @@
+# This configuration was generated by
+# `rubocop --auto-gen-config --auto-gen-only-exclude`
+# on 2021-09-17 06:40:32 UTC using RuboCop version 1.18.4.
+# The point is for the user to remove these configuration records
+# one by one as the offenses are removed from the code base.
+# Note that changes in the inspected code, or installation of new
+# versions of RuboCop, may require this file to be generated again.
+
+# Offense count: 1
+# Configuration parameters: AllowComments.
+Lint/EmptyClass:
+  Exclude:
+    - 'lib/jekyll-seo-tag/version.rb'
+
+# Offense count: 3
+Lint/NoReturnInBeginEndBlocks:
+  Exclude:
+    - 'lib/jekyll-seo-tag/author_drop.rb'
+    - 'lib/jekyll-seo-tag/drop.rb'
+
+# Offense count: 1
+# Cop supports --auto-correct.
+Lint/ToJSON:
+  Exclude:
+    - 'lib/jekyll-seo-tag/json_ld_drop.rb'
+
+# Offense count: 1
+# Configuration parameters: IgnoredMethods, Max.
+Metrics/PerceivedComplexity:
+  Exclude:
+    - 'lib/jekyll-seo-tag/drop.rb'
+
+# Offense count: 1
+# Configuration parameters: MinSize.
+Performance/CollectionLiteralInLoop:
+  Exclude:
+    - 'spec/jekyll_seo_tag/author_drop_spec.rb'
+
+# Offense count: 9
+# Cop supports --auto-correct.
+Style/RedundantBegin:
+  Exclude:
+    - 'lib/jekyll-seo-tag.rb'
+    - 'lib/jekyll-seo-tag/author_drop.rb'
+    - 'lib/jekyll-seo-tag/drop.rb'
+    - 'lib/jekyll-seo-tag/image_drop.rb'

.travis.yml

@@ -1,7 +0,0 @@
-rvm:
-  - 2.2.3
-before_install: gem install bundler
-language: ruby
-script: script/cibuild
-sudo: false
-cache: bundler

Gemfile

@@ -1,16 +1,8 @@
+# frozen_string_literal: true
+
 source "https://rubygems.org"
-require "json"
-require "open-uri"
 
 gemspec
 
-group :development, :test do
-  versions = JSON.parse(open("https://pages.github.com/versions.json").read)
-  versions.delete("ruby")
-  versions.delete("jekyll-seo-tag")
-  versions.delete("github-pages")
-
-  versions.each do |dep, version|
-    gem dep, version
-  end
-end
+gem "jekyll", ENV["JEKYLL_VERSION"] if ENV["JEKYLL_VERSION"]
+gem "kramdown-parser-gfm" if ENV["JEKYLL_VERSION"] == "~> 3.9"

History.markdown

@@ -1,7 +1,186 @@
 ## HEAD
 
-* Convert template logic to a Liquid Drop (significant performance improvement) (#184)
-* Fix for JSON-LD validation warning for images missing required properties (#183)
+### Development Fixes
+
+  * Add Ruby 3.1 to CI matrix (#459)
+  * chore: remove git.io (#462)
+
+### Minor Enhancements
+
+  * Added the `twitter:description` tag (#464)
+  * Support for image paths relative to the page's directory (#466)
+  * Truncate the description value to 100 words (#492)
+
+## 2.8.0 / 2022-02-04
+
+### Minor Enhancements
+
+  * Allow to set type for author (#427)
+  * Allow setting `author.url` (#453)
+  * Implement Facebook domain verification (#455)
+  * Add `og:image:alt` and `twitter:image:alt` (#438)
+  * Sort JSON-LD data by key (#458)
+
+### Bug Fixes
+
+  * Set the default `og:type` to 'website' (#391)
+  * Template: Remove double new line (#454)
+
+### Development Fixes
+
+  * Fix typo in source code comment (#449)
+  * Set up Continuous Integration via GH Actions (#450)
+  * Bump RuboCop to v1.18.x (#452)
+  * Add workflow to release gem via GH Actions
+
+## 2.7.1 / 2020-10-18
+
+### Development Fixes
+
+  * refactor: mutate site payload instead of duplicating it (#419)
+
+## 2.7.0 / 2020-10-18
+
+### Minor Enhancements
+
+  * Change pagination message with `seo_paginator_message` option (#324)
+  * Make Twitter Summary Card without having Twitter account (#284)
+  * Prefer site.tagline to site.description for page title (#356)
+  * Render og:locale meta only when defined explicitly (#388)
+
+### Bug Fixes
+
+  * Ensure a single leading `@` for twitter usernames (#367)
+
+### Development Fixes
+
+  * chore(deps): require Ruby > 2.4.0 EOL
+  * test: fix locale specs that use the fallback locale (#360)
+  * refactor: Replace read-only empty hash with private constant (#418)
+  * refactor: Mutate hash literals instead of duplicating them (#417)
+  * refactor: Reduce allocations of instance-agnostic objects (#376)
+  * refactor: Memoize #author_hash in SeoTag::AuthorDrop (#342)
+  * refactor: simplify conditional in SeoTag::Drop#date_modified (#343)
+  * chore(ci): profile seo-tag plugin on a third-party repository (#414)
+  * chore(ci): Jekyll v4.0 (#372)
+  * chore(ci): test against current stable Ruby 2.5 and 2.7 (#385)
+  * style: align with latest jekyll-rubocop (#382)
+  * fix: Travis builds for Jekyll 3.x (#415)
+
+### Documentation
+
+  * Structured Data Testing Tool is deprecated (#409)
+  * Rename Google webmaster tools to Google Search Console  (#403)
+  * Improve documentation on plugin usage (#399)
+  * remove Google+ from example snippet (#358)
+  * HTTPS link to https://ogp.me/ (#359)
+  * HTTPS links to schema.org (#350)
+  * use example.com for example URL (#351)
+
+## 2.6.1 / 2019-05-17
+
+### Development Fixes
+
+  * Test against Jekyll 4.x (#336)
+
+## 2.6.0 / 2019-03-16
+
+### Minor Enhancements
+
+  * Twitter Image and Title (#330)
+
+### Bug Fixes
+
+  * Do not cache the drop payload for SeoTag (#306)
+  * Update url of schema website (#296)
+
+### Development Fixes
+
+  * Relax version constraint on Bundler (#325)
+  * chore(ci): Add Ruby 2.6, drop Ruby 2.3 (#326)
+  * chore (ci): remove deprecated `sudo: false` in .travis.yml (#333)
+  * Lint Ruby code with rubocop-jekyll gem (#302)
+  * chore(deps): bump rubocop-jekyll to v0.4 (#320)
+  * chore(deps): bump rubocop-jekyll to v0.3 (#316)
+  * Correct RuboCop offenses in spec files (#319)
+
+### Documentation
+
+  * Rectify error in Usage documentation (#328)
+
+## 2.5.0 / 2018-05-18
+
+  * Docs: Prevent GitHub Pages from processing Liquid raw tag (#276)
+
+### Documentation
+
+  * Use gems config key for Jekyll < 3.5.0 (#255)
+  * docs/usage - replace "below" with correct link (#280)
+
+### Development Fixes
+
+  * Test against Ruby 2.5 (#260)
+  * add tests for twitter.card types (#289)
+  * Target Ruby 2.3 and Rubocop 0.56.0 (#292)
+
+### Minor Enhancements
+
+  * Add webmaster_verifications for baidu (#263)
+  * Include page number in title (#250)
+  * Configure default Twitter summary card type (V2) (#225)
+
+## 2.4.0 / 2017-12-04
+
+### Minor
+
+  * Add meta generator (#236)
+  * Consistently use self-closing tags (#246)
+  * Strip null values from JSON-LD hash (#249)
+
+### Documentation
+
+  * Avoid deprecation warning when building docs (#243)
+
+### Development Fixes
+
+  * Test against latest Rubies (#242)
+  * Use Nokigiri on CI (#181)
+
+## 2.3.0
+
+### Minor Enhancements
+
+  * Use canonical_url specified in page if present #211
+  * Fix for image.path causing an invalid url error #228
+  * Ensure `site.data.authors` is properly formatted before attempting to retrieve author meta #227
+  * Convert author, image, and JSON-LD to dedicated drops #229
+  * Cache parsed template #231
+  * Define path with `__dir__` #232
+
+### Documentation
+
+  * gems: is deprecated in current Jekyll version of github-pages #230
+
+## 2.2.3
+
+  * Guard against the author's Twitter handle being Nil when stripping @'s #203
+  * Guard against empty title or description strings #206
+
+## 2.2.2
+
+### Minor Enhancements
+
+  * Guard against arrays in subhashes #197
+  * Guard against invalid or missing URLs #199
+
+### Development fixes
+
+  * Remove dynamic GitHub Pages logic from Gemfile #194
+
+## 2.2.1
+
+  * Convert template logic to a Liquid Drop (significant performance improvement) (#184)
+  * Fix for JSON-LD validation warning for images missing required properties (#183)
 
 ## 2.2.0
 
@@ -11,7 +190,7 @@
   * Add og:locale support #166
   * Add support for Bing and Yandex webmaster tools. Closes #147 (#148)
   * Add SEO author and date modified to validate JSON-LD output (#151)
-  
+
 ### Minor Enhancements
 
   * Use `|` for title separator (#162)

LICENSE.txt

@@ -1,6 +1,6 @@
 The MIT License (MIT)
 
-Copyright (c) 2015 Ben Balter
+Copyright (c) 2015-present Ben Balter and the jekyll-seo-tag contributors
 
 Permission is hereby granted, free of charge, to any person obtaining a copy
 of this software and associated documentation files (the "Software"), to deal

README.md

@@ -1,226 +0,0 @@
-# Jekyll SEO Tag
-
-A Jekyll plugin to add metadata tags for search engines and social networks to better index and display your site's content.
-
-[![Gem Version](https://badge.fury.io/rb/jekyll-seo-tag.svg)](https://badge.fury.io/rb/jekyll-seo-tag) [![Build Status](https://travis-ci.org/jekyll/jekyll-seo-tag.svg)](https://travis-ci.org/jekyll/jekyll-seo-tag)
-
-## What it does
-
-Jekyll SEO Tag adds the following meta tags to your site:
-
-* Page title, with site title or description appended
-* Page description
-* Canonical URL
-* Next and previous URLs on paginated pages
-* [JSON-LD Site and post metadata](https://developers.google.com/structured-data/) for richer indexing
-* [Open Graph](http://ogp.me/) title, description, site title, and URL (for Facebook, LinkedIn, etc.)
-* [Twitter Summary Card](https://dev.twitter.com/cards/overview) metadata
-
-While you could theoretically add the necessary metadata tags yourself, Jekyll SEO Tag provides a battle-tested template of crowdsourced best-practices.
-
-## What it doesn't do
-
-Jekyll SEO tag is designed to output machine-readable metadata for search engines and social networks to index and display. If you're looking for something to analyze your Jekyll site's structure and content (e.g., more traditional SEO optimization), take a look at [The Jekyll SEO Gem](https://github.com/pmarsceill/jekyll-seo-gem).
-
-Jekyll SEO tag isn't designed to accommodate every possible use case. It should work for most site out of the box and without a laundry list of configuration options that serve only to confuse most users.
-
-## Installation
-
-1. Add the following to your site's `Gemfile`:
-
-  ```ruby
-  gem 'jekyll-seo-tag'
-  ```
-
-2. Add the following to your site's `_config.yml`:
-
-  ```yml
-  gems:
-    - jekyll-seo-tag
-  ```
-
-3. Add the following right before `</head>` in your site's template(s):
-
-  ```liquid
-  {% seo %}
-  ```
-
-## Usage
-
-The SEO tag will respect any of the following if included in your site's `_config.yml` (and simply not include them if they're not defined):
-
-* `title` - Your site's title (e.g., Ben's awesome site, The GitHub Blog, etc.)
-* `description` - A short description (e.g., A blog dedicated to reviewing cat gifs)
-* `url` - The full URL to your site. Note: `site.github.url` will be used by default.
-* `author` - global author information (see below)
-* `twitter:username` - The site's Twitter handle. You'll want to describe it like so:
-
-  ```yml
-  twitter:
-    username: benbalter
-  ```
-
-* `facebook` - The following properties are available:
-  * `facebook:app_id` - a Facebook app ID for Facebook insights
-  * `facebook:publisher` - a Facebook page URL or ID of the publishing entity
-  * `facebook:admins` - a Facebook user ID for domain insights linked to a personal account
-
-  You'll want to describe one or more like so:
-
-   ```yml
-  facebook:
-    app_id: 1234
-    publisher: 1234
-    admins: 1234
-   ```
-
-* `logo` - URL to a site-wide logo (e.g., `/assets/your-company-logo.png`)
-* `social` - For [specifying social profiles](https://developers.google.com/structured-data/customize/social-profiles). The following properties are available:
-  * `name` - If the user or organization name differs from the site's name
-  * `links` - An array of links to social media profiles.
-  * `date_modified` - Manually specify the `dateModified` field in the JSON-LD output to override Jekyll's own `dateModified`. This field will take **first priority** for the `dateModified` JSON-LD output. This is useful when the file timestamp does not match the true time that the content was modified. A user may also install [Last Modified At](https://github.com/gjtorikian/jekyll-last-modified-at) which will offer an alternative way of providing for the `dateModified` field.
-
-  ```yml
-  social:
-    name: Ben Balter
-    links:
-      - https://twitter.com/BenBalter
-      - https://www.facebook.com/ben.balter
-      - https://www.linkedin.com/in/BenBalter
-      - https://plus.google.com/+BenBalter
-      - https://github.com/benbalter
-      - https://keybase.io/benbalter
-    ```
-
-* `google_site_verification` for verifying ownership via Google webmaster tools
-* Alternatively, verify ownership with several services at once using the following format:
-
-```yml
-webmaster_verifications:
-  google: 1234
-  bing: 1234
-  alexa: 1234
-  yandex: 1234
-```
-
-* `lang` - The locale these tags are marked up in. Of the format `language_TERRITORY`. Default is `en_US`.
-
-The SEO tag will respect the following YAML front matter if included in a post, page, or document:
-
-* `title` - The title of the post, page, or document
-* `description` - A short description of the page's content
-* `image` - URL to an image associated with the post, page, or document (e.g., `/assets/page-pic.jpg`)
-* `author` - Page-, post-, or document-specific author information (see below)
-* `lang` - Page-, post-, or document-specific language information
-
-## Advanced usage
-
-Jekyll SEO Tag is designed to implement SEO best practices by default and to be the right fit for most sites right out of the box. If for some reason, you need more control over the output, read on:
-
-### Disabling `<title>` output
-
-If for some reason, you don't want the plugin to output `<title>` tags on each page, simply invoke the plugin within your template like so:
-
-```
-{% seo title=false %}
-```
-
-### Author information
-
-Author information is used to propagate the `creator` field of Twitter summary cards. This should be an author-specific, not site-wide Twitter handle (the site-wide username be stored as `site.twitter.username`).
-
-*TL;DR: In most cases, put `author: [your Twitter handle]` in the document's front matter, for sites with multiple authors. If you need something more complicated, read on.*
-
-There are several ways to convey this author-specific information. Author information is found in the following order of priority:
-
-1. An `author` object, in the documents's front matter, e.g.:
-
-  ```yml
-  author:
-    twitter: benbalter
-  ```
-
-2. An `author` object, in the site's `_config.yml`, e.g.:
-
-  ```yml
-  author:
-    twitter: benbalter
-  ```
-
-3. `site.data.authors[author]`, if an author is specified in the document's front matter, and a corresponding key exists in `site.data.authors`. E.g., you have the following in the document's front matter:
-
-  ```yml
-  author: benbalter
-  ```
-
-  And you have the following in `_data/authors.yml`:
-
-  ```yml
-  benbalter:
-    picture: /img/benbalter.png
-    twitter: jekyllrb
-
-  potus:
-    picture: /img/potus.png
-    twitter: whitehouse
-  ```
-
-  In the above example, the author `benbalter`'s Twitter handle will be resolved to `@jekyllrb`. This allows you to centralize author information in a single `_data/authors` file for site with many authors that require more than just the author's username.
-
-  *Pro-tip: If `authors` is present in the document's front matter as an array (and `author` is not), the plugin will use the first author listed, as Twitter supports only one author.*
-
-4. An author in the document's front matter (the simplest way), e.g.:
-
-  ```yml
-  author: benbalter
-  ```
-
-5. An author in the site's `_config.yml`, e.g.:
-
-  ```yml
-  author: benbalter
-  ```
-
-### Customizing JSON-LD output
-
-The following options can be set for any particular page. While the default options are meant to serve most users in the most common circumstances, there may be situations where more precise control is necessary.
-
-* `seo`
-  * `name` - If the name of the thing that the page represents is different from the page title. (i.e.: "Frank's Café" vs "Welcome to Frank's Café")
-  * `type` - The type of things that the page represents. This must be a [Schema.org type](http://schema.org/docs/schemas.html), and will probably usually be something like [`BlogPosting`](http://schema.org/BlogPosting), [`NewsArticle`](http://schema.org/NewsArticle), [`Person`](http://schema.org/Person), [`Organization`](http://schema.org/Organization), etc.
-  * `links` - An array of other URLs that represent the same thing that this page represents. For instance, Jane's bio page might include links to Jane's GitHub and Twitter profiles.
-
-### Customizing image output
-
-For most users, setting `image: [path-to-image]` on a per-page basis should be enough. If you need more control over how images are represented, the `image` property can also be an object, with the following options:
-
-* `path` - The relative path to the image. Same as `image: [path-to-image]`
-* `height` - The height of the Open Graph (`og:image`) image
-* `width` - The width of the Open Graph (`og:image`) image
-
-You can use any of the above, optional properties, like so:
-
-```yml
-image:
-  path: /img/twitter.png
-  height: 100
-  width: 100
-```
-
-### Setting a default image
-
-You can define a default image using [Front Matter default](https://jekyllrb.com/docs/configuration/#front-matter-defaults), to provide a default Twitter Card or OGP image to all of your posts and pages.
-
-Here is a very basic example, that you are encouraged to adapt to your needs:
-
-```yml
-defaults:
-  - scope:
-      path: ""
-    values:
-      image: /assets/images/default-card.png
-```
-
-### SmartyPants Titles
-
-Titles will be processed using [Jekyll's `smartify` filter](https://jekyllrb.com/docs/templates/). This will use SmartyPants to translate plain ASCII punctuation into "smart" typographic punctuation. This will not render or strip any Markdown you may be using in a page title.

docs/README.md

@@ -0,0 +1,33 @@
+## About Jekyll SEO Tag
+
+A Jekyll plugin to add metadata tags for search engines and social networks to better index and display your site's content.
+
+[![Gem Version](https://badge.fury.io/rb/jekyll-seo-tag.svg)](https://badge.fury.io/rb/jekyll-seo-tag) [![Build Status](https://travis-ci.org/jekyll/jekyll-seo-tag.svg)](https://travis-ci.org/jekyll/jekyll-seo-tag)
+
+## What it does
+
+Jekyll SEO Tag adds the following meta tags to your site:
+
+* Page title, with site title or description appended
+* Page description
+* Canonical URL
+* Next and previous URLs on paginated pages
+* [JSON-LD Site and post metadata](https://developers.google.com/search/docs/guides/intro-structured-data) for richer indexing
+* [Open Graph](https://ogp.me/) title, description, site title, and URL (for Facebook, LinkedIn, etc.)
+* [Twitter Summary Card](https://dev.twitter.com/cards/overview) metadata
+
+While you could theoretically add the necessary metadata tags yourself, Jekyll SEO Tag provides a battle-tested template of crowdsourced best-practices.
+
+## What it doesn't do
+
+Jekyll SEO tag is designed to output machine-readable metadata for search engines and social networks to index and display. If you're looking for something to analyze your Jekyll site's structure and content (e.g., more traditional SEO optimization), take a look at [The Jekyll SEO Gem](https://github.com/pmarsceill/jekyll-seo-gem).
+
+Jekyll SEO tag isn't designed to accommodate every possible use case. It should work for most site out of the box and without a laundry list of configuration options that serve only to confuse most users.
+
+## Documentation
+
+For more information, see:
+
+* [Installation](installation.md)
+* [Usage](usage.md)
+* [Advanced usage](advanced-usage.md)

docs/_config.yml

@@ -0,0 +1,10 @@
+title: Jekyll SEO Tag
+description: A Jekyll plugin to add metadata tags for search engines and social networks to better index and display your site's content.
+
+permalink: pretty
+
+plugins:
+  - jekyll-seo-tag
+  - jekyll-sitemap
+
+theme: jekyll-theme-primer

docs/_layouts/default.html

@@ -0,0 +1,18 @@
+<!DOCTYPE html>
+<html lang="en">
+  <head>
+    <meta charset="UTF-8">
+    <meta name="viewport" content="width=device-width, initial-scale=1">
+    <link href="{{ '/assets/css/style.css?v=' | append: site.github.build_revision | relative_url }}" rel="stylesheet">
+    {% seo %}
+  </head>
+  <body>
+    <div class="container markdown-body">
+      <h1>{{ site.title }}</h1>
+      
+      {{ content }}
+    </div>
+    <script src="{{ "assets/javascript/anchor-js/anchor.min.js" | relative_url }}"></script>
+    <script>anchors.add();</script>
+  </body>
+</html>

docs/advanced-usage.md

@@ -0,0 +1,191 @@
+## Advanced usage
+
+Jekyll SEO Tag is designed to implement SEO best practices by default and to be the right fit for most sites right out of the box. If for some reason, you need more control over the output, read on:
+
+### Disabling `<title>` output
+
+If for some reason, you don't want the plugin to output `<title>` tags on each page, simply invoke the plugin within your template like so:
+
+<!-- {% raw %} -->
+```
+{% seo title=false %}
+```
+<!-- {% endraw %} -->
+
+### Author information
+
+Author information is used to propagate the `creator` field of Twitter summary cards. This should be an author-specific, not site-wide Twitter handle (the site-wide username be stored as `site.twitter.username`).
+
+*TL;DR: In most cases, put `author: [your Twitter handle]` in the document's front matter, for sites with multiple authors. If you need something more complicated, read on.*
+
+There are several ways to convey this author-specific information. Author information is found in the following order of priority:
+
+1. An `author` object, in the documents's front matter, e.g.:
+
+  ```yml
+  author:
+    twitter: benbalter
+  ```
+
+2. An `author` object, in the site's `_config.yml`, e.g.:
+
+  ```yml
+  author:
+    twitter: benbalter
+  ```
+
+3. `site.data.authors[author]`, if an author is specified in the document's front matter, and a corresponding key exists in `site.data.authors`. E.g., you have the following in the document's front matter:
+
+  ```yml
+  author: benbalter
+  ```
+
+  And you have the following in `_data/authors.yml`:
+
+  ```yml
+  benbalter:
+    picture: /img/benbalter.png
+    twitter: jekyllrb
+
+  potus:
+    picture: /img/potus.png
+    twitter: whitehouse
+  ```
+
+  In the above example, the author `benbalter`'s Twitter handle will be resolved to `@jekyllrb`. This allows you to centralize author information in a single `_data/authors` file for site with many authors that require more than just the author's username.
+
+  *Pro-tip: If `authors` is present in the document's front matter as an array (and `author` is not), the plugin will use the first author listed, as Twitter supports only one author.*
+
+4. An author in the document's front matter (the simplest way), e.g.:
+
+  ```yml
+  author: benbalter
+  ```
+
+5. An author in the site's `_config.yml`, e.g.:
+
+  ```yml
+  author: benbalter
+  ```
+
+#### Setting author url
+
+Starting from August 6, 2021 [Google recommends](https://developers.google.com/search/updates) to set the `author.url` property. This property helps Google to disambiguate the correct author of the article.
+
+You can set it the same way as the other author properties. For example, you can put it in an `author` object, in the site's `_config.yml`, e.g.:
+
+  ```yml
+  author:
+    name: My Name
+    url: https://example.com/
+  ```
+
+### Customizing description length
+
+By default, the description is limited to the first 100 words of the full content.
+
+You can adjust this limit at the page level, by using the `seo_description_max_words` page property:
+
+```yml
+  seo_description_max_words: 200
+```
+
+You can also set a default site-wide value for all pages using [Front Matter defaults](https://jekyllrb.com/docs/configuration/front-matter-defaults/) in your `_config.yml` file:
+
+```yml
+defaults:
+  - scope:
+      path: ""
+    values:
+      seo_description_max_words: 200
+```
+
+
+### Customizing JSON-LD output
+
+The following options can be set for any particular page. While the default options are meant to serve most users in the most common circumstances, there may be situations where more precise control is necessary.
+
+* `seo`
+  * `name` - If the name of the thing that the page represents is different from the page title. (i.e.: "Frank's Café" vs "Welcome to Frank's Café")
+  * `type` - The type of things that the page represents. This must be a [Schema.org type](https://schema.org/docs/schemas.html), and will probably usually be something like [`BlogPosting`](https://schema.org/BlogPosting), [`NewsArticle`](https://schema.org/NewsArticle), [`Person`](https://schema.org/Person), [`Organization`](https://schema.org/Organization), etc.
+  * `links` - An array of other URLs that represent the same thing that this page represents. For instance, Jane's bio page might include links to Jane's GitHub and Twitter profiles.
+  * `date_modified` - Manually specify the `dateModified` field in the JSON-LD output to override Jekyll's own `dateModified`.
+  This field will take **first priority** for the `dateModified` JSON-LD output. This is useful when the file timestamp does not match the true time that the content was modified. A user may also install [Last Modified At](https://github.com/gjtorikian/jekyll-last-modified-at) which will offer an alternative way of providing for the `dateModified` field.
+
+### Customizing image output
+
+For most users, setting `image: [path-to-image]` on a per-page basis should be enough. If you need more control over how images are represented, the `image` property can also be an object, with the following options:
+
+* `path` - The relative path to the image. Same as `image: [path-to-image]`
+* `height` - The height of the Open Graph (`og:image`) image
+* `width` - The width of the Open Graph (`og:image`) image
+* `alt` - The alternative image text for Open Graph (`og:image:alt`) and Twitter (`twitter:image:alt`)
+
+You can use any of the above, optional properties, like so:
+
+```yml
+image:
+  path: /img/twitter.png
+  height: 100
+  width: 100
+  alt: Twitter Logo
+```
+
+### Setting a default image
+
+You can define a default image using [Front Matter defaults](https://jekyllrb.com/docs/configuration/front-matter-defaults/), to provide a default Twitter Card or OGP image to all of your posts and pages.
+
+Here is a very basic example, that you are encouraged to adapt to your needs:
+
+```yml
+defaults:
+  - scope:
+      path: ""
+    values:
+      image: /assets/images/default-card.png
+```
+
+### SmartyPants Titles
+
+Titles will be processed using [Jekyll's `smartify` filter](https://jekyllrb.com/docs/liquid/filters/). This will use SmartyPants to translate plain ASCII punctuation into "smart" typographic punctuation. This will not render or strip any Markdown you may be using in a page title.
+
+### Setting customized Canonical URL
+
+You can set custom Canonical URL for a page by specifying canonical_url option in page front matter.
+E.g., you have the following in the page's front matter:
+```yml
+layout: post
+title: Title of Your Post
+canonical_url: 'https://github.com/jekyll/jekyll-seo-tag/'
+```
+
+Which will generate canonical_url with specified link in canonical_url.
+```html
+<link rel="canonical" href="https://github.com/jekyll/jekyll-seo-tag/" />
+```
+
+If no canonical_url option was specified, then uses page url for generating canonical_url.
+E.g., you have not specified canonical_url in front matter:
+```yml
+layout: post
+title: Title of Your Post
+```
+
+Which will generate following canonical_url:
+```html
+<link rel="canonical" href="https://example.com/title-of-your-post" />
+```
+
+### Customizing title modifier for paginated pages
+
+You can override the default title modifier for paginated pages from `Page %{current} of %{total} for ` to a string of your
+choice by setting a `seo_paginator_message` key in your `_config.yml`.
+
+For example:
+
+```yml
+seo_paginator_message: "%<current>s / %<total>s | "
+```
+
+While the value can be any string text, we recommend using a Ruby string-template containing the variables `current` and `total`
+similar to the example above, to incorporate the current page-number and total number of paginated pages in the title.

docs/installation.md

@@ -0,0 +1,24 @@
+# Installing Jekyll SEO Tag
+
+1. Add the following to your site's `Gemfile`:
+
+  ```ruby
+  gem 'jekyll-seo-tag'
+  ```
+
+2. Add the following to your site's `_config.yml`:
+
+  ```yml
+  plugins:
+    - jekyll-seo-tag
+  ```
+
+If you are using a Jekyll version less than `3.5.0`, use the `gems` key instead of `plugins`.
+
+3. Add the following right before `</head>` in your site's template(s):
+
+<!-- {% raw %} -->
+  ```liquid
+  {% seo %}
+  ```
+<!-- {% endraw %} -->

docs/usage.md

@@ -0,0 +1,81 @@
+## Usage
+
+The SEO tag will respect any of the following if included in your site's `_config.yml` (and simply not include them if
+they're not defined):
+
+* `title` - Your site's title (e.g., *Ben's Awesome Site*, *The GitHub Blog*, etc.), used as part of the title tag like
+`Home | Ben's Awesome Site`.
+* `tagline` - A short description (e.g., *A blog dedicated to reviewing cat gifs*), used as part of the title tag like
+`Ben's Awesome Site | A blog dedicated to reviewing cat gifs` instead of `Ben's Awesome Site | Long description about a
+blog dedicated to reviewing cat gifs` that would be used when `page.title` is not defined.
+* `description` - A longer description used for the description meta tag. Also used as fallback for pages that don't
+provide their own `description`, and also as part of the page's title tag if neither `page.title` nor `site.tagline`
+has been defined.
+* `url` - The full URL to your site. Note: `site.github.url` will be used by default.
+* `author` - global author information (see [Advanced usage](advanced-usage.md#author-information))
+* `twitter` - The following properties are available:
+  * `twitter:card` - The site's default card type
+  * `twitter:username` - The site's Twitter handle.
+
+  You'll want to describe them like so:
+
+  ```yml
+  twitter:
+    username: benbalter
+    card: summary
+  ```
+* `facebook` - The following properties are available:
+  * `facebook:app_id` - a Facebook app ID for Facebook insights
+  * `facebook:publisher` - a Facebook page URL or ID of the publishing entity
+  * `facebook:admins` - a Facebook user ID for domain insights linked to a personal account
+
+  You'll want to describe one or more like so:
+
+  ```yml
+  facebook:
+    app_id: 1234
+    publisher: 1234
+    admins: 1234
+  ```
+* `logo` - URL to a site-wide logo (e.g., `/assets/your-company-logo.png`) - If you would like the "publisher" property
+to be present, you must add this field to your site's configuration, during the validation of the structured data by
+Google Search Console, if the `logo` field is not validated, you will find errors inherent to the publisher in the
+[Rich Results Testing Tool](https://search.google.com/test/rich-results)
+* `social` - For [specifying social profiles](https://developers.google.com/search/docs/guides/enhance-site#add-your-sites-name-logo-and-social-links).
+The following properties are available:
+  * `name` - If the user or organization name differs from the site's name
+  * `links` - An array of links to social media profiles.
+
+  ```yml
+  social:
+    name: Ben Balter
+    links:
+      - https://twitter.com/BenBalter
+      - https://www.facebook.com/ben.balter
+      - https://www.linkedin.com/in/BenBalter
+      - https://github.com/benbalter
+      - https://keybase.io/benbalter
+  ```
+* `google_site_verification` for verifying ownership via Google Search Console
+* Alternatively, verify ownership with several services at once using the following format:
+  ```yml
+  webmaster_verifications:
+    google: 1234
+    bing: 1234
+    alexa: 1234
+    yandex: 1234
+    baidu: 1234
+    facebook: 1234
+  ```
+* `locale` - The locale these tags are marked up in. Of the format `language_TERRITORY`. Default is `en_US`. Takes priority
+over existing config key `lang`.
+
+The SEO tag will respect the following YAML front matter if included in a post, page, or document:
+
+* `title` - The title of the post, page, or document
+* `description` - A short description of the page's content
+* `image` - URL to an image associated with the post, page, or document (e.g., `/assets/page-pic.jpg`)
+* `author` - Page-, post-, or document-specific author information (see [Advanced usage](advanced-usage.md#author-information))
+* `locale` - Page-, post-, or document-specific locale information. Takes priority over existing front matter attribute `lang`.
+
+*Note:* Front matter defaults can be used for any of the above values as described in advanced usage with an image example.

jekyll-seo-tag.gemspec

@@ -1,8 +1,6 @@
-# coding: utf-8
+# frozen_string_literal: true
 
-lib = File.expand_path("../lib", __FILE__)
-$LOAD_PATH.unshift(lib) unless $LOAD_PATH.include?(lib)
-require "jekyll-seo-tag/version"
+require_relative "lib/jekyll-seo-tag/version"
 
 Gem::Specification.new do |spec|
   spec.name          = "jekyll-seo-tag"
@@ -10,7 +8,7 @@ Gem::Specification.new do |spec|
   spec.authors       = ["Ben Balter"]
   spec.email         = ["ben.balter@github.com"]
   spec.summary       = "A Jekyll plugin to add metadata tags for search engines and social networks to better index and display your site's content."
-  spec.homepage      = "https://github.com/benbalter/jekyll-seo-tag"
+  spec.homepage      = "https://github.com/jekyll/jekyll-seo-tag"
   spec.license       = "MIT"
 
   # Prevent pushing this gem to RubyGems.org by setting 'allowed_push_host', or
@@ -21,14 +19,16 @@ Gem::Specification.new do |spec|
     raise "RubyGems 2.0 or newer is required to protect against public gem pushes."
   end
 
+  spec.required_ruby_version = ">= 2.5.0"
+
   spec.files         = `git ls-files -z`.split("\x0").reject { |f| f.match(%r!^(test|spec|features)/!) }
   spec.bindir        = "exe"
   spec.executables   = spec.files.grep(%r!^exe/!) { |f| File.basename(f) }
   spec.require_paths = ["lib"]
 
-  spec.add_dependency "jekyll", "~> 3.3"
-  spec.add_development_dependency "bundler", "~> 1.14"
+  spec.add_dependency "jekyll", ">= 3.8", "< 5.0"
+  spec.add_development_dependency "bundler", ">= 1.15"
+  spec.add_development_dependency "html-proofer", "~> 3.7"
   spec.add_development_dependency "rspec", "~> 3.5"
-  spec.add_development_dependency "html-proofer", "~> 3.6"
-  spec.add_development_dependency "rubocop", "~> 0.48"
+  spec.add_development_dependency "rubocop-jekyll", "~> 0.12.0"
 end

lib/jekyll-seo-tag.rb

@@ -1,11 +1,17 @@
+# frozen_string_literal: true
+
 require "jekyll"
 require "jekyll-seo-tag/version"
 
 module Jekyll
   class SeoTag < Liquid::Tag
-    autoload :JSONLD,  "jekyll-seo-tag/json_ld"
-    autoload :Drop,    "jekyll-seo-tag/drop"
-    autoload :Filters, "jekyll-seo-tag/filters"
+    autoload :JSONLD,     "jekyll-seo-tag/json_ld"
+    autoload :AuthorDrop, "jekyll-seo-tag/author_drop"
+    autoload :ImageDrop,  "jekyll-seo-tag/image_drop"
+    autoload :JSONLDDrop, "jekyll-seo-tag/json_ld_drop"
+    autoload :UrlHelper,  "jekyll-seo-tag/url_helper"
+    autoload :Drop,       "jekyll-seo-tag/drop"
+    autoload :Filters,    "jekyll-seo-tag/filters"
 
     attr_accessor :context
 
@@ -18,7 +24,7 @@ module Jekyll
     # We will not strip any whitespace if the next character is a '-'
     #   so that we do not interfere with the HTML comment at the
     #   very begining
-    MINIFY_REGEX = %r!(?<=[{}]|[>,]\n)\s+(?\!-)!
+    MINIFY_REGEX = %r!(?<=[{}]|[>,]\n)\s+(?\!-)!.freeze
 
     def initialize(_tag_name, text, _tokens)
       super
@@ -27,7 +33,7 @@ module Jekyll
 
     def render(context)
       @context = context
-      template.render!(payload, info)
+      SeoTag.template.render!(payload, info)
     end
 
     private
@@ -40,16 +46,20 @@ module Jekyll
     end
 
     def payload
-      {
-        "page"      => context.registers[:page],
-        "site"      => context.registers[:site].site_payload["site"],
-        "paginator" => context["paginator"],
-        "seo_tag"   => drop,
-      }
+      # site_payload is an instance of UnifiedPayloadDrop. See https://github.com/jekyll/jekyll/blob/22f2724a1f117a94cc16d18c499a93d5915ede4f/lib/jekyll/site.rb#L261-L276
+      context.registers[:site].site_payload.tap do |site_payload|
+        site_payload["page"]      = context.registers[:page]
+        site_payload["paginator"] = context["paginator"]
+        site_payload["seo_tag"]   = drop
+      end
     end
 
     def drop
-      @drop ||= Jekyll::SeoTag::Drop.new(@text, @context)
+      if context.registers[:site].liquid_renderer.respond_to?(:cache)
+        Jekyll::SeoTag::Drop.new(@text, @context)
+      else
+        @drop ||= Jekyll::SeoTag::Drop.new(@text, @context)
+      end
     end
 
     def info
@@ -59,19 +69,23 @@ module Jekyll
       }
     end
 
-    def template
-      @template ||= Liquid::Template.parse template_contents
-    end
-
-    def template_contents
-      @template_contents ||= begin
-        File.read(template_path).gsub(MINIFY_REGEX, "")
+    class << self
+      def template
+        @template ||= Liquid::Template.parse template_contents
       end
-    end
 
-    def template_path
-      @template_path ||= begin
-        File.expand_path "./template.html", File.dirname(__FILE__)
+      private
+
+      def template_contents
+        @template_contents ||= begin
+          File.read(template_path).gsub(MINIFY_REGEX, "")
+        end
+      end
+
+      def template_path
+        @template_path ||= begin
+          File.expand_path "./template.html", File.dirname(__FILE__)
+        end
       end
     end
   end

lib/jekyll-seo-tag/author_drop.rb

@@ -0,0 +1,93 @@
+# frozen_string_literal: true
+
+module Jekyll
+  class SeoTag
+    # A drop representing the current page's author
+    #
+    # Author name will be pulled from:
+    #
+    # 1. The page's `author` key
+    # 2. The first author in the page's `authors` key
+    # 3. The `author` key in the site config
+    #
+    # If the result from the name search is a string, we'll also check
+    # for additional author metadata in `site.data.authors`
+    class AuthorDrop < Jekyll::Drops::Drop
+      # Initialize a new AuthorDrop
+      #
+      # page - The page hash (e.g., Page#to_liquid)
+      # site - The Jekyll::Drops::SiteDrop
+      def initialize(page: nil, site: nil)
+        raise ArgumentError unless page && site
+
+        @mutations = {}
+        @page = page
+        @site = site
+      end
+
+      # AuthorDrop#to_s should return name, allowing the author drop to safely
+      # replace `page.author`, if necessary, and remain backwards compatible
+      def name
+        author_hash["name"]
+      end
+      alias_method :to_s, :name
+
+      def twitter
+        return @twitter if defined? @twitter
+
+        twitter = author_hash["twitter"] || author_hash["name"]
+        @twitter = twitter.is_a?(String) ? twitter.sub(%r!^@!, "") : nil
+      end
+
+      private
+
+      attr_reader :site, :page
+
+      # Finds the page author in the page.author, page.authors, or site.author
+      #
+      # Returns a string or hash representing the author
+      def resolved_author
+        return @resolved_author if defined? @resolved_author
+
+        sources = [page["author"]]
+        sources << page["authors"].first if page["authors"].is_a?(Array)
+        sources << site["author"]
+        @resolved_author = sources.find { |s| !s.to_s.empty? }
+      end
+
+      # If resolved_author is a string, attempts to find coresponding author
+      # metadata in `site.data.authors`
+      #
+      # Returns a hash representing additional metadata or an empty hash
+      def site_data_hash
+        @site_data_hash ||= begin
+          return {} unless resolved_author.is_a?(String)
+          return {} unless site.data["authors"].is_a?(Hash)
+
+          author_hash = site.data["authors"][resolved_author]
+          author_hash.is_a?(Hash) ? author_hash : {}
+        end
+      end
+
+      # Returns the normalized author hash representing the page author,
+      # including site-wide metadata if the author is provided as a string,
+      # or an empty hash, if the author cannot be resolved
+      def author_hash
+        @author_hash ||= begin
+          case resolved_author
+          when Hash
+            resolved_author
+          when String
+            { "name" => resolved_author }.merge!(site_data_hash)
+          else
+            {}
+          end
+        end
+      end
+
+      # Since author_hash is aliased to fallback_data, any values in the hash
+      # will be exposed via the drop, allowing support for arbitrary metadata
+      alias_method :fallback_data, :author_hash
+    end
+  end
+end

lib/jekyll-seo-tag/drop.rb

@@ -1,18 +1,23 @@
+# frozen_string_literal: true
+
 module Jekyll
   class SeoTag
     class Drop < Jekyll::Drops::Drop
-      include Jekyll::SeoTag::JSONLD
+      include Jekyll::SeoTag::UrlHelper
 
-      TITLE_SEPARATOR = " | ".freeze
-      FORMAT_STRING_METHODS = %i[
-        markdownify strip_html normalize_whitespace escape_once
+      TITLE_SEPARATOR = " | "
+      FORMAT_STRING_METHODS = [
+        :markdownify, :strip_html, :normalize_whitespace, :escape_once,
       ].freeze
-      HOMEPAGE_OR_ABOUT_REGEX = %r!^/(about/)?(index.html?)?$!
+      HOMEPAGE_OR_ABOUT_REGEX = %r!^/(about/)?(index.html?)?$!.freeze
+
+      EMPTY_READ_ONLY_HASH = {}.freeze
+      private_constant :EMPTY_READ_ONLY_HASH
 
       def initialize(text, context)
-        @obj = {}
+        @obj = EMPTY_READ_ONLY_HASH
         @mutations = {}
-        @text    = text
+        @text = text
         @context = context
       end
 
@@ -24,6 +29,7 @@ module Jekyll
       def title?
         return false unless title
         return @display_title if defined?(@display_title)
+
         @display_title = (@text !~ %r!title=false!i)
       end
 
@@ -31,75 +37,83 @@ module Jekyll
         @site_title ||= format_string(site["title"] || site["name"])
       end
 
+      def site_tagline
+        @site_tagline ||= format_string site["tagline"]
+      end
+
+      def site_description
+        @site_description ||= format_string site["description"]
+      end
+
       # Page title without site title or description appended
       def page_title
-        @page_title ||= format_string(page["title"] || site_title)
+        @page_title ||= format_string(page["title"]) || site_title
+      end
+
+      def site_tagline_or_description
+        site_tagline || site_description
       end
 
       # Page title with site title or description appended
+      # rubocop:disable Metrics/CyclomaticComplexity
       def title
         @title ||= begin
-          if page["title"] && site_title
+          if site_title && page_title != site_title
             page_title + TITLE_SEPARATOR + site_title
-          elsif site["description"] && site_title
-            site_title + TITLE_SEPARATOR + format_string(site["description"])
+          elsif site_description && site_title
+            site_title + TITLE_SEPARATOR + site_tagline_or_description
           else
             page_title || site_title
           end
         end
+
+        return page_number + @title if page_number
+
+        @title
       end
+      # rubocop:enable Metrics/CyclomaticComplexity
 
       def name
         return @name if defined?(@name)
+
         @name = if seo_name
                   seo_name
                 elsif !homepage_or_about?
                   nil
-                elsif site["social"] && site["social"]["name"]
-                  format_string site["social"]["name"]
+                elsif site_social["name"]
+                  format_string site_social["name"]
                 elsif site_title
-                  format_string site_title
+                  site_title
                 end
       end
 
       def description
-        @description ||= format_string(
-          page["description"] || page["excerpt"] || site["description"]
-        )
+        @description ||= begin
+          value = format_string(page["description"] || page["excerpt"]) || site_description
+          snippet(value, description_max_words)
+        end
       end
 
-      # Returns a nil or a hash representing the author
-      # Author name will be pulled from:
-      #
-      # 1. The `author` key, if the key is a string
-      # 2. The first author in the `authors` key
-      # 3. The `author` key in the site config
-      #
-      # If the result from the name search is a string, we'll also check
-      # to see if the author exists in `site.data.authors`
+      # A drop representing the page author
       def author
-        @author ||= begin
-          return if author_string_or_hash.to_s.empty?
+        @author ||= AuthorDrop.new(:page => page, :site => site)
+      end
 
-          author = if author_string_or_hash.is_a?(String)
-                     author_hash(author_string_or_hash)
-                   else
-                     author_string_or_hash
-                   end
+      # A drop representing the JSON-LD output
+      def json_ld
+        @json_ld ||= JSONLDDrop.new(self)
+      end
 
-          author["twitter"] ||= author["name"]
-          author["twitter"].delete! "@"
-          author.to_liquid
-        end
+      # Returns a Drop representing the page's image
+      # Returns nil if the image has no path, to preserve backwards compatability
+      def image
+        @image ||= ImageDrop.new(:page => page, :context => @context)
+        @image if @image.path
       end
 
       def date_modified
         @date_modified ||= begin
-          date = if page["seo"] && page["seo"]["date_modified"]
-                   page["seo"]["date_modified"]
-                 else
-                   page["last_modified_at"] || page["date"]
-                 end
+          date = page_seo["date_modified"] || page["last_modified_at"].to_liquid || page["date"]
           filters.date_to_xmlschema(date) if date
         end
       end
@@ -110,8 +124,8 @@ module Jekyll
 
       def type
         @type ||= begin
-          if page["seo"] && page["seo"]["type"]
-            page["seo"]["type"]
+          if page_seo["type"]
+            page_seo["type"]
           elsif homepage_or_about?
             "WebSite"
           elsif page["date"]
@@ -124,10 +138,10 @@ module Jekyll
 
       def links
         @links ||= begin
-          if page["seo"] && page["seo"]["links"]
-            page["seo"]["links"]
-          elsif homepage_or_about? && site["social"] && site["social"]["links"]
-            site["social"]["links"]
+          if page_seo["links"]
+            page_seo["links"]
+          elsif homepage_or_about? && site_social["links"]
+            site_social["links"]
           end
         end
       end
@@ -135,6 +149,7 @@ module Jekyll
       def logo
         @logo ||= begin
           return unless site["logo"]
+
           if absolute_url? site["logo"]
             filters.uri_escape site["logo"]
           else
@@ -143,39 +158,26 @@ module Jekyll
         end
       end
 
-      # Returns nil or a hash representing the page image
-      # The image hash will always contain a path, pulled from:
-      #
-      # 1. The `image` key if it's a string
-      # 2. The `image.path` key if it's a hash
-      # 3. The `image.facebook` key
-      # 4. The `image.twitter` key
-      #
-      # The resulting path is always an absolute URL
-      def image
-        return @image if defined?(@image)
-
-        image = page["image"]
-        return @image = nil unless image
-
-        image = { "path" => image } if image.is_a?(String)
-        image["path"] ||= image["facebook"] || image["twitter"]
-
-        unless absolute_url? image["path"]
-          image["path"] = filters.absolute_url image["path"]
-        end
-
-        image["path"] = filters.uri_escape image["path"]
-
-        @image = image.to_liquid
-      end
-
       def page_lang
         @page_lang ||= page["lang"] || site["lang"] || "en_US"
       end
 
+      def page_locale
+        @page_locale ||= (page["locale"] || site["locale"] || page_lang).tr("-", "_")
+      end
+
       def canonical_url
-        @canonical_url ||= filters.absolute_url(page["url"]).gsub(%r!/index\.html$!, "/")
+        @canonical_url ||= begin
+          if page["canonical_url"].to_s.empty?
+            filters.absolute_url(page["url"]).to_s.gsub(%r!/index\.html$!, "/")
+          else
+            page["canonical_url"]
+          end
+        end
+      end
+
+      def description_max_words
+        @description_max_words ||= page["seo_description_max_words"] || 100
       end
 
       private
@@ -196,16 +198,22 @@ module Jekyll
         page["url"] =~ HOMEPAGE_OR_ABOUT_REGEX
       end
 
+      def page_number
+        return unless @context["paginator"] && @context["paginator"]["page"]
+
+        current = @context["paginator"]["page"]
+        total = @context["paginator"]["total_pages"]
+        paginator_message = site["seo_paginator_message"] || "Page %<current>s of %<total>s for "
+
+        format(paginator_message, :current => current, :total => total) if current > 1
+      end
+
       attr_reader :context
 
       def fallback_data
         @fallback_data ||= {}
       end
 
-      def absolute_url?(string)
-        Addressable::URI.parse(string).absolute?
-      end
-
       def format_string(string)
         string = FORMAT_STRING_METHODS.reduce(string) do |memo, method|
           filters.public_send(method, memo)
@@ -214,27 +222,37 @@ module Jekyll
         string unless string.empty?
       end
 
-      def author_string_or_hash
-        @author_string_or_hash ||= begin
-          author = page["author"]
-          author = page["authors"][0] if author.to_s.empty? && page["authors"]
-          author = site["author"] if author.to_s.empty?
-          author
-        end
-      end
+      def snippet(string, max_words)
+        return string if string.nil?
 
-      def author_hash(author_string)
-        if site.data["authors"] && site.data["authors"][author_string]
-          hash = site.data["authors"][author_string]
-          hash["twitter"] ||= author_string
-          hash
-        else
-          { "name" => author_string }
-        end
+        result = string.split(%r!\s+!, max_words + 1)[0...max_words].join(" ")
+        result.length < string.length ? result.concat("…") : result
       end
 
       def seo_name
-        @seo_name ||= format_string(page["seo"]["name"]) if page["seo"]
+        @seo_name ||= format_string(page_seo["name"]) if page_seo["name"]
+      end
+
+      def page_seo
+        @page_seo ||= sub_hash(page, "seo")
+      end
+
+      def site_social
+        @site_social ||= sub_hash(site, "social")
+      end
+
+      # Safely returns a sub hash
+      #
+      # hash - the parent hash
+      # key  - the key in the parent hash
+      #
+      # Returns the sub hash or an empty hash, if it does not exist
+      def sub_hash(hash, key)
+        if hash[key].is_a?(Hash)
+          hash[key]
+        else
+          EMPTY_READ_ONLY_HASH
+        end
       end
     end
   end

lib/jekyll-seo-tag/filters.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module Jekyll
   class SeoTag
     class Filters

lib/jekyll-seo-tag/image_drop.rb

@@ -0,0 +1,83 @@
+# frozen_string_literal: true
+
+module Jekyll
+  class SeoTag
+    # A drop representing the page image
+    # The image path will be pulled from:
+    #
+    # 1. The `image` key if it's a string
+    # 2. The `image.path` key if it's a hash
+    # 3. The `image.facebook` key
+    # 4. The `image.twitter` key
+    class ImageDrop < Jekyll::Drops::Drop
+      include Jekyll::SeoTag::UrlHelper
+
+      # Initialize a new ImageDrop
+      #
+      # page - The page hash (e.g., Page#to_liquid)
+      # context - the Liquid::Context
+      def initialize(page: nil, context: nil)
+        raise ArgumentError unless page && context
+
+        @mutations = {}
+        @page = page
+        @context = context
+      end
+
+      # Called path for backwards compatability, this is really
+      # the escaped, absolute URL representing the page's image
+      # Returns nil if no image path can be determined
+      def path
+        @path ||= filters.uri_escape(absolute_url) if absolute_url
+      end
+      alias_method :to_s, :path
+
+      private
+
+      attr_accessor :page, :context
+
+      # The normalized image hash with a `path` key (which may be nil)
+      def image_hash
+        @image_hash ||= begin
+          image_meta = page["image"]
+
+          case image_meta
+          when Hash
+            { "path" => nil }.merge!(image_meta)
+          when String
+            { "path" => image_meta }
+          else
+            { "path" => nil }
+          end
+        end
+      end
+      alias_method :fallback_data, :image_hash
+
+      def raw_path
+        @raw_path ||= begin
+          image_hash["path"] || image_hash["facebook"] || image_hash["twitter"]
+        end
+      end
+
+      def absolute_url
+        return unless raw_path
+
+        @absolute_url ||= build_absolute_path
+      end
+
+      def build_absolute_path
+        return raw_path unless raw_path.is_a?(String) && absolute_url?(raw_path) == false
+        return filters.absolute_url(raw_path) if raw_path.start_with?("/")
+
+        page_dir = @page["url"]
+        page_dir = File.dirname(page_dir) unless page_dir.end_with?("/")
+
+        filters.absolute_url File.join(page_dir, raw_path)
+      end
+
+      def filters
+        @filters ||= Jekyll::SeoTag::Filters.new(context)
+      end
+    end
+  end
+end

lib/jekyll-seo-tag/json_ld.rb

@@ -1,8 +1,10 @@
+# frozen_string_literal: true
+
 module Jekyll
   class SeoTag
+    # This module is deprecated, but is included in the Gem to avoid a breaking
+    # change and should be removed at the next major version bump
     module JSONLD
-
-      # A hash of instance methods => key in resulting JSON-LD hash
       METHODS_KEYS = {
         :json_context   => "@context",
         :type           => "@type",
@@ -19,60 +21,10 @@ module Jekyll
         :canonical_url  => "url",
       }.freeze
 
+      # Self should be a Jekyll::SeoTag::Drop instance (when extending the module)
       def json_ld
-        @json_ld ||= begin
-          output = {}
-          METHODS_KEYS.each do |method, key|
-            value = send(method)
-            output[key] = value unless value.nil?
-          end
-          output
-        end
-      end
-
-      private
-
-      def json_context
-        "http://schema.org"
-      end
-
-      def json_author
-        return unless author
-        {
-          "@type" => "Person",
-          "name"  => author["name"],
-        }
-      end
-
-      def json_image
-        return unless image
-        return image["path"] if image.length == 1
-
-        hash = image.dup
-        hash["url"]   = hash.delete("path")
-        hash["@type"] = "imageObject"
-        hash
-      end
-
-      def publisher
-        return unless logo
-        output = {
-          "@type" => "Organization",
-          "logo"  => {
-            "@type" => "ImageObject",
-            "url"   => logo,
-          },
-        }
-        output["name"] = author["name"] if author
-        output
-      end
-
-      def main_entity
-        return unless %w(BlogPosting CreativeWork).include?(type)
-        {
-          "@type" => "WebPage",
-          "@id"   => canonical_url,
-        }
+        Jekyll.logger.warn "Jekyll::SeoTag::JSONLD is deprecated"
+        @json_ld ||= JSONLDDrop.new(self)
       end
     end
   end

lib/jekyll-seo-tag/json_ld_drop.rb

@@ -0,0 +1,104 @@
+# frozen_string_literal: true
+
+module Jekyll
+  class SeoTag
+    class JSONLDDrop < Jekyll::Drops::Drop
+      extend Forwardable
+
+      def_delegator :page_drop, :name,           :name
+      def_delegator :page_drop, :description,    :description
+      def_delegator :page_drop, :canonical_url,  :url
+      def_delegator :page_drop, :page_title,     :headline
+      def_delegator :page_drop, :date_modified,  :dateModified
+      def_delegator :page_drop, :date_published, :datePublished
+      def_delegator :page_drop, :links,          :sameAs
+      def_delegator :page_drop, :logo,           :logo
+      def_delegator :page_drop, :type,           :type
+
+      # Expose #type and #logo as private methods and #@type as a public method
+      alias_method :@type, :type
+      private :type, :logo
+
+      VALID_ENTITY_TYPES = %w(BlogPosting CreativeWork).freeze
+      VALID_AUTHOR_TYPES = %w(Organization Person).freeze
+      private_constant :VALID_ENTITY_TYPES, :VALID_AUTHOR_TYPES
+
+      # page_drop should be an instance of Jekyll::SeoTag::Drop
+      def initialize(page_drop)
+        @mutations = {}
+        @page_drop = page_drop
+      end
+
+      def fallback_data
+        @fallback_data ||= {
+          "@context" => "https://schema.org",
+        }
+      end
+
+      def author
+        return unless page_drop.author["name"]
+
+        author_type = page_drop.author["type"]
+        return if author_type && !VALID_AUTHOR_TYPES.include?(author_type)
+
+        hash = {
+          "@type" => author_type || "Person",
+          "name"  => page_drop.author["name"],
+        }
+
+        author_url = page_drop.author["url"]
+        hash["url"] = author_url if author_url
+
+        hash
+      end
+
+      def image
+        return unless page_drop.image
+        return page_drop.image.path if page_drop.image.keys.length == 1
+
+        hash = page_drop.image.to_h
+        hash["url"]   = hash.delete("path")
+        hash["@type"] = "imageObject"
+        hash
+      end
+
+      def publisher
+        return unless logo
+
+        output = {
+          "@type" => "Organization",
+          "logo"  => {
+            "@type" => "ImageObject",
+            "url"   => logo,
+          },
+        }
+        output["name"] = page_drop.author.name if page_drop.author.name
+        output
+      end
+
+      def main_entity
+        return unless VALID_ENTITY_TYPES.include?(type)
+
+        {
+          "@type" => "WebPage",
+          "@id"   => page_drop.canonical_url,
+        }
+      end
+      alias_method :mainEntityOfPage, :main_entity
+      private :main_entity
+
+      # Returns a JSON-encoded object containing the JSON-LD data.
+      # Keys are sorted.
+      def to_json(state = nil)
+        keys.sort.each_with_object({}) do |(key, _), result|
+          v = self[key]
+          result[key] = v unless v.nil?
+        end.to_json(state)
+      end
+
+      private
+
+      attr_reader :page_drop
+    end
+  end
+end

lib/jekyll-seo-tag/url_helper.rb

@@ -0,0 +1,23 @@
+# frozen_string_literal: true
+
+module Jekyll
+  class SeoTag
+    # Mixin to share common URL-related methods between class
+    module UrlHelper
+      private
+
+      # Determines if the given string is an absolute URL
+      #
+      # Returns true if an absolute URL
+      # Returns false if it's a relative URL
+      # Returns nil if it is not a string or can't be parsed as a URL
+      def absolute_url?(string)
+        return unless string
+
+        Addressable::URI.parse(string).absolute?
+      rescue Addressable::URI::InvalidURIError
+        nil
+      end
+    end
+  end
+end

lib/jekyll-seo-tag/version.rb

@@ -1,8 +1,10 @@
+# frozen_string_literal: true
+
 # Prevent bundler errors
 module Liquid; class Tag; end; end
 
 module Jekyll
   class SeoTag < Liquid::Tag
-    VERSION = "2.2.0".freeze
+    VERSION = "2.8.0"
   end
 end

lib/template.html

@@ -3,6 +3,8 @@
   <title>{{ seo_tag.title }}</title>
 {% endif %}
 
+<meta name="generator" content="Jekyll v{{ jekyll.version }}" />
+
 {% if seo_tag.page_title %}
   <meta property="og:title" content="{{ seo_tag.page_title }}" />
 {% endif %}
@@ -11,11 +13,12 @@
   <meta name="author" content="{{ seo_tag.author.name }}" />
 {% endif %}
 
-<meta property="og:locale" content="{{ seo_tag.page_lang | replace:'-','_' }}" />
+<meta property="og:locale" content="{{ seo_tag.page_locale }}" />
 
 {% if seo_tag.description %}
   <meta name="description" content="{{ seo_tag.description }}" />
   <meta property="og:description" content="{{ seo_tag.description }}" />
+  <meta property="twitter:description" content="{{ seo_tag.description }}" />
 {% endif %}
 
 {% if site.url %}
@@ -35,31 +38,45 @@
   {% if seo_tag.image.width %}
     <meta property="og:image:width" content="{{ seo_tag.image.width }}" />
   {% endif %}
+  {% if seo_tag.image.alt %}
+    <meta property="og:image:alt" content="{{ seo_tag.image.alt }}" />
+  {% endif %}
 {% endif %}
 
 {% if page.date %}
   <meta property="og:type" content="article" />
   <meta property="article:published_time" content="{{ page.date | date_to_xmlschema }}" />
+{% else %}
+  <meta property="og:type" content="website" />
 {% endif %}
 
 {% if paginator.previous_page %}
-  <link rel="prev" href="{{ paginator.previous_page_path | absolute_url }}">
+  <link rel="prev" href="{{ paginator.previous_page_path | absolute_url }}" />
 {% endif %}
 {% if paginator.next_page %}
-  <link rel="next" href="{{ paginator.next_page_path | absolute_url }}">
+  <link rel="next" href="{{ paginator.next_page_path | absolute_url }}" />
+{% endif %}
+
+{% if seo_tag.image %}
+  <meta name="twitter:card" content="{{ page.twitter.card | default: site.twitter.card | default: "summary_large_image" }}" />
+  <meta property="twitter:image" content="{{ seo_tag.image.path }}" />
+{% else %}
+  <meta name="twitter:card" content="summary" />
+{% endif %}
+
+{% if seo_tag.image.alt %}
+  <meta name="twitter:image:alt" content="{{ seo_tag.image.alt }}" />
+{% endif %}
+
+{% if seo_tag.page_title %}
+  <meta property="twitter:title" content="{{ seo_tag.page_title }}" />
 {% endif %}
 
 {% if site.twitter %}
-  {% if seo_tag.image %}
-    <meta name="twitter:card" content="summary_large_image" />
-  {% else %}
-    <meta name="twitter:card" content="summary" />
-  {% endif %}
-
-  <meta name="twitter:site" content="@{{ site.twitter.username | replace:"@","" }}" />
+  <meta name="twitter:site" content="@{{ site.twitter.username | remove:'@' }}" />
 
   {% if seo_tag.author.twitter %}
-    <meta name="twitter:creator" content="@{{ seo_tag.author.twitter }}" />
+    <meta name="twitter:creator" content="@{{ seo_tag.author.twitter | remove:'@' }}" />
   {% endif %}
 {% endif %}
 
@@ -79,19 +96,27 @@
 
 {% if site.webmaster_verifications %}
   {% if site.webmaster_verifications.google %}
-    <meta name="google-site-verification" content="{{ site.webmaster_verifications.google }}">
+    <meta name="google-site-verification" content="{{ site.webmaster_verifications.google }}" />
   {% endif %}
 
   {% if site.webmaster_verifications.bing %}
-    <meta name="msvalidate.01" content="{{ site.webmaster_verifications.bing }}">
+    <meta name="msvalidate.01" content="{{ site.webmaster_verifications.bing }}" />
   {% endif %}
 
   {% if site.webmaster_verifications.alexa %}
-    <meta name="alexaVerifyID" content="{{ site.webmaster_verifications.alexa }}">
+    <meta name="alexaVerifyID" content="{{ site.webmaster_verifications.alexa }}" />
   {% endif %}
 
   {% if site.webmaster_verifications.yandex %}
-    <meta name="yandex-verification" content="{{ site.webmaster_verifications.yandex }}">
+    <meta name="yandex-verification" content="{{ site.webmaster_verifications.yandex }}" />
+  {% endif %}
+
+  {% if site.webmaster_verifications.baidu %}
+    <meta name="baidu-site-verification" content="{{ site.webmaster_verifications.baidu }}" />
+  {% endif %}
+
+  {% if site.webmaster_verifications.facebook %}
+    <meta name="facebook-domain-verification" content="{{ site.webmaster_verifications.facebook }}" />
   {% endif %}
 {% elsif site.google_site_verification %}
   <meta name="google-site-verification" content="{{ site.google_site_verification }}" />

script/site

@@ -0,0 +1,3 @@
+#!/bin/sh
+
+bundle exec jekyll serve --source docs

spec/fixtures/_posts/2017-01-03-.md

@@ -0,0 +1,6 @@
+---
+---
+
+# A post without a title
+
+*See* https://github.com/jekyll/jekyll-seo-tag/commit/4f80ea50b773d1995985e35a8a63806516c353c4#commitcomment-22010563

spec/jekyll_seo_tag/author_drop_spec.rb

@@ -0,0 +1,164 @@
+# frozen_string_literal: true
+
+RSpec.describe Jekyll::SeoTag::AuthorDrop do
+  let(:data) { {} }
+  let(:config) { { "author" => "site_author" } }
+  let(:site) do
+    site = make_site(config)
+    site.data = data
+    site
+  end
+  let(:site_payload) { site.site_payload["site"] }
+
+  let(:name) { "foo" }
+  let(:twitter) { "foo" }
+  let(:picture) { nil }
+  let(:expected_hash) do
+    {
+      "name"    => name,
+      "twitter" => twitter,
+    }
+  end
+
+  let(:page_meta) { { "title" => "page title" } }
+  let(:page)      { make_page(page_meta) }
+  subject { described_class.new(:page => page.to_liquid, :site => site_payload.to_liquid) }
+
+  before do
+    Jekyll.logger.log_level = :error
+  end
+
+  it "returns the author's name for #to_s" do
+    expect(subject.to_s).to eql("site_author")
+  end
+
+  context "with site.authors as an array" do
+    let("data") { { "authors" => %w(foo bar) } }
+    let(:page_meta) { { "author" => "foo" } }
+
+    it "doesn't error" do
+      expect(subject.to_h).to eql(expected_hash)
+    end
+  end
+
+  context "with site.authors[author] as string" do
+    let("data") { { "authors" => { "foo" => "bar" } } }
+    let(:page_meta) { { "author" => "foo" } }
+
+    it "doesn't error" do
+      expect(subject.to_h).to eql(expected_hash)
+    end
+  end
+
+  [:with, :without].each do |site_data_type|
+    context "#{site_data_type} site.author data" do
+      let(:data) do
+        if site_data_type == :with
+          {
+            "authors" => {
+              "author"        => { "name" => "data_author", "image" => "author.png" },
+              "array_author"  => { "image" => "author.png" },
+              "string_author" => { "image" => "author.png" },
+              "site_author"   => { "image" => "author.png" },
+            },
+          }
+        else
+          {}
+        end
+      end
+
+      {
+        :string       => { "author" => "string_author" },
+        :array        => { "authors" => %w(array_author author2) },
+        :empty_string => { "author" => "" },
+        :nil          => { "author" => nil },
+        :hash         => { "author" => { "name" => "hash_author" } },
+      }.each do |author_type, data|
+        context "with author as #{author_type}" do
+          let(:page_meta) { data }
+          let(:expected_author) do
+            "#{author_type}_author".sub("nil_", "site_").sub("empty_string_", "site_")
+          end
+
+          it "returns the name" do
+            expect(subject["name"]).to eql(expected_author)
+          end
+
+          it "returns the twitter handle" do
+            expect(subject["twitter"]).to eql(expected_author)
+          end
+
+          if site_data_type == :with && author_type != :hash
+            it "returns arbitrary metadata" do
+              expect(subject["image"]).to eql("author.png")
+            end
+          end
+        end
+      end
+    end
+  end
+
+  context "with author as a front matter default" do
+    let(:config) do
+      {
+        "defaults" => [
+          {
+            "scope"  => { "path" => "" },
+            "values" => { "author" => "front matter default" },
+          },
+        ],
+      }
+    end
+
+    it "uses the author from the front matter default" do
+      expect(subject["name"]).to eql("front matter default")
+    end
+  end
+
+  context "twitter" do
+    let(:page_meta) { { "author" => "author" } }
+
+    it "pulls the handle from the author" do
+      expect(subject["twitter"]).to eql("author")
+    end
+
+    context "with an @" do
+      let(:page_meta) do
+        {
+          "author" => {
+            "name"    => "author",
+            "twitter" => "@twitter",
+          },
+        }
+      end
+
+      it "strips the @" do
+        expect(subject["twitter"]).to eql("twitter")
+      end
+    end
+
+    # See https://github.com/jekyll/jekyll-seo-tag/issues/202
+    context "without an author name or handle" do
+      let(:page_meta) { { "author" => { "foo" => "bar" } } }
+
+      it "dosen't blow up" do
+        expect(subject["twitter"]).to be_nil
+      end
+    end
+
+    context "with an explicit handle" do
+      let(:page_meta) do
+        {
+          "author" => {
+            "name"    => "author",
+            "twitter" => "twitter",
+          },
+        }
+      end
+
+      it "pulls the handle from the hash" do
+        expect(subject["twitter"]).to eql("twitter")
+      end
+    end
+  end
+end

spec/jekyll_seo_tag/drop_spec.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 RSpec.describe Jekyll::SeoTag::Drop do
   let(:config)    { { "title" => "site title" } }
   let(:page_meta) { { "title" => "page title" } }
@@ -82,6 +84,17 @@ RSpec.describe Jekyll::SeoTag::Drop do
         end
       end
 
+      context "with a site tagline but no page title" do
+        let(:page)  { make_page }
+        let(:config) do
+          { "title" => "site title", "description" => "site description", "tagline" => "site tagline" }
+        end
+
+        it "builds the title" do
+          expect(subject.title).to eql("site title | site tagline")
+        end
+      end
+
       context "with just a page title" do
         let(:site)  { make_site }
 
@@ -97,6 +110,40 @@ RSpec.describe Jekyll::SeoTag::Drop do
           expect(subject.title).to eql("site title")
         end
       end
+
+      context "without a page or site title" do
+        let(:page)  { make_page }
+        let(:site)  { make_site }
+
+        it "returns nil" do
+          expect(subject.title).to be_nil
+        end
+      end
+
+      context "with an empty page title" do
+        let(:page_meta) { { :title => "" } }
+
+        it "builds the title" do
+          expect(subject.title).to eql("site title")
+        end
+      end
+
+      context "with an empty site title" do
+        let(:config) { { :title => "" } }
+
+        it "builds the title" do
+          expect(subject.title).to eql("page title")
+        end
+      end
+
+      context "with an empty page and site title" do
+        let(:page_meta) { { :title => "" } }
+        let(:config) { { :title => "" } }
+
+        it "returns nil" do
+          expect(subject.title).to be_nil
+        end
+      end
     end
   end
 
@@ -122,12 +169,38 @@ RSpec.describe Jekyll::SeoTag::Drop do
         end
       end
 
+      context "with site.social as an array" do
+        let(:config) { { "social" => %w(a b) } }
+
+        it "uses site.social.name" do
+          expect(subject.name).to be_nil
+        end
+      end
+
       it "uses the site title" do
         expect(subject.name).to eql("site title")
       end
     end
 
-    context "description" do
+    context "site description" do
+      context "with a site description" do
+        let(:config) { { :description => "site description " } }
+
+        it "returns the site discription" do
+          expect(subject.site_description).to eql("site description")
+        end
+      end
+
+      context "without a site description" do
+        let(:site) { make_site }
+
+        it "returns nil" do
+          expect(subject.site_description).to be_nil
+        end
+      end
+    end
+
+    context "page description" do
       context "with a page description" do
         let(:page_meta) { { "description"=> "page description" } }
 
@@ -151,96 +224,63 @@ RSpec.describe Jekyll::SeoTag::Drop do
           expect(subject.description).to eql("site description")
         end
       end
+
+      context "with no descriptions" do
+        let(:page_meta) { { "description" => nil, "excerpt" => nil } }
+        let(:config) { { "description"=> nil } }
+
+        it "uses returns nil" do
+          expect(subject.description).to be_nil
+        end
+      end
+
+      context "truncation" do
+        context "without seo_description_max_words" do
+          let(:page_meta) { { "description" => "word " * 150 } }
+
+          it "truncates the description to the first 200 words" do
+            expect(subject.description).to eql(("word " * 100).chop.concat("…"))
+          end
+        end
+
+        context "with an explicit seo_description_max_words property" do
+          let(:page_meta) { { "description" => "For a long time, I went to bed early", "seo_description_max_words" => 6 } }
+
+          it "truncates the description to the configured words count" do
+            expect(subject.description).to eql("For a long time, I went…")
+          end
+        end
+      end
     end
 
     context "author" do
-      let(:data) { {} }
-      let(:config) { { "author" => "author" } }
-      let(:site) do
-        site = make_site(config)
-        site.data = data
-        site
+      let(:page_meta) { { "author" => "foo" } }
+
+      it "returns an AuthorDrop" do
+        expect(subject.author).to be_a(Jekyll::SeoTag::AuthorDrop)
       end
 
-      %i[with without].each do |site_data_type|
-        context "#{site_data_type} site.author data" do
-          let(:data) do
-            if site_data_type == :with
-              {
-                "authors" => {
-                  "author" => { "name" => "Author" },
-                },
-              }
-            else
-              {}
-            end
-          end
+      it "passes page information" do
+        expect(subject.author.name).to eql("foo")
+      end
 
+      # Regression test to ensure to_liquid is called on site and page
+      # before being passed to AuthorDrop
+      context "with author as a front matter default" do
+        let(:page_meta) { {} }
+        let(:config) do
           {
-            :string       => { "author" => "author" },
-            :array        => { "authors" => %w(author author2) },
-            :empty_string => { "author" => "" },
-            :nil          => { "author" => nil },
-            :hash         => { "author" => { "name" => "author" } },
-          }.each do |author_type, data|
-            context "with author as #{author_type}" do
-              let(:page_meta) { data }
-
-              it "returns a hash" do
-                expect(subject.author).to be_a(Hash)
-              end
-
-              it "returns the name" do
-                if site_data_type == :with && author_type != :hash
-                  expect(subject.author["name"]).to eql("Author")
-                else
-                  expect(subject.author["name"]).to eql("author")
-                end
-              end
-
-              it "returns the twitter handle" do
-                expect(subject.author["twitter"]).to eql("author")
-              end
-            end
-          end
-        end
-      end
-
-      context "twitter" do
-        let(:page_meta) { { "author" => "author" } }
-
-        it "pulls the handle from the author" do
-          expect(subject.author["twitter"]).to eql("author")
-        end
-
-        context "with an @" do
-          let(:page_meta) do
-            {
-              "author" => {
-                "name"    => "author",
-                "twitter" => "@twitter",
+            "defaults" => [
+              {
+                "scope"  => { "path" => "" },
+                "values" => { "author" => "front matter default" },
               },
-            }
-          end
-
-          it "strips the @" do
-            expect(subject.author["twitter"]).to eql("twitter")
-          end
+            ],
+          }
         end
 
-        context "with an explicit handle" do
-          let(:page_meta) do
-            {
-              "author" => {
-                "name"    => "author",
-                "twitter" => "twitter",
-              },
-            }
-          end
-
-          it "pulls the handle from the hash" do
-            expect(subject.author["twitter"]).to eql("twitter")
-          end
+        it "uses the author from the front matter default" do
+          expect(subject.author["name"]).to eql("front matter default")
         end
       end
     end
@@ -292,6 +332,14 @@ RSpec.describe Jekyll::SeoTag::Drop do
       end
     end
 
+    context "with seo as an array" do
+      let(:page_meta) { { "seo" => %w(a b) } }
+
+      it "uses seo.type" do
+        expect(subject.type).to eql("WebPage")
+      end
+    end
+
     context "the homepage" do
       let(:page_meta) { { "permalink" => "/" } }
 
@@ -301,7 +349,7 @@ RSpec.describe Jekyll::SeoTag::Drop do
     end
 
     context "the about page" do
-      let(:page) { make_page({ "permalink" => "/about/" }) }
+      let(:page) { make_page("permalink" => "/about/") }
 
       it "is a website" do
         expect(subject.type).to eql("WebSite")
@@ -385,69 +433,15 @@ RSpec.describe Jekyll::SeoTag::Drop do
   end
 
   context "image" do
+    let(:image) { "/foo.png" }
     let(:page_meta) { { "image" => image } }
 
-    context "with image as a string" do
-      let(:image) { "image.png" }
-
-      it "returns a hash" do
-        expect(subject.image).to be_a(Hash)
-      end
-
-      it "returns the image" do
-        expect(subject.image["path"]).to eql("/image.png")
-      end
-
-      context "with site.url" do
-        let(:config) { { "url" => "http://example.com" } }
-
-        it "makes the path absolute" do
-          expect(subject.image["path"]).to eql("http://example.com/image.png")
-        end
-      end
-
-      context "with a URL-escaped path" do
-        let(:image) { "some image.png" }
-
-        it "URL-escapes the image" do
-          expect(subject.image["path"]).to eql("/some%20image.png")
-        end
-      end
+    it "returns a Drop" do
+      expect(subject.image).to be_a(Jekyll::SeoTag::ImageDrop)
     end
 
-    context "with image as a hash" do
-      context "with a path" do
-        let(:image) { { "path" => "image.png" } }
-
-        it "returns the image" do
-          expect(subject.image["path"]).to eql("/image.png")
-        end
-      end
-
-      context "with facebook" do
-        let(:image) { { "facebook" => "image.png" } }
-
-        it "returns the image" do
-          expect(subject.image["path"]).to eql("/image.png")
-        end
-      end
-
-      context "with twitter" do
-        let(:image) { { "twitter" => "image.png" } }
-
-        it "returns the image" do
-          expect(subject.image["path"]).to eql("/image.png")
-        end
-      end
-
-      context "with height and width" do
-        let(:image) { { "path" => "image.png", "height" => 5, "width" => 10 } }
-
-        it "returns the height and width" do
-          expect(subject.image["height"]).to eql(5)
-          expect(subject.image["width"]).to eql(10)
-        end
-      end
+    it "returns the image" do
+      expect(subject.image["path"]).to eql("/foo.png")
     end
   end
 
@@ -497,4 +491,48 @@ RSpec.describe Jekyll::SeoTag::Drop do
       end
     end
   end
+
+  context "canonical url" do
+    let(:config) { { :url => "http://example.com" } }
+
+    context "when canonical url is specified for a page" do
+      let(:canonical_url) { "https://github.com/jekyll/jekyll-seo-tag/" }
+      let(:page_meta) { { "title" => "page title", "canonical_url" => canonical_url } }
+
+      it "uses specified canonical url" do
+        expect(subject.canonical_url).to eq(canonical_url)
+      end
+    end
+
+    context "when canonical url is not specified for a page" do
+      it "uses site specific canonical url" do
+        expect(subject.canonical_url).to eq("http://example.com/page.html")
+      end
+    end
+  end
+
+  context "pagination" do
+    let(:context) do
+      make_context(
+        { :page => page, :site => site },
+        "paginator" => { "page" => 2, "total_pages" => 10 }
+      )
+    end
+
+    it "render default pagination title" do
+      expect(subject.send(:page_number)).to eq("Page 2 of 10 for ")
+    end
+
+    context "render custom pagination title" do
+      let(:config) { { "seo_paginator_message" => "%<current>s of %<total>s" } }
+
+      it "renders the correct page number" do
+        expect(subject.send(:page_number)).to eq("2 of 10")
+      end
+    end
+  end
+
+  it "exposes the JSON-LD drop" do
+    expect(subject.json_ld).to be_a(Jekyll::SeoTag::JSONLDDrop)
+  end
 end

spec/jekyll_seo_tag/filters_spec.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 RSpec.describe Jekyll::SeoTag::Filters do
   let(:page)      { make_page }
   let(:site)      { make_site }

spec/jekyll_seo_tag/image_drop_spec.rb

@@ -0,0 +1,121 @@
+# frozen_string_literal: true
+
+RSpec.describe Jekyll::SeoTag::ImageDrop do
+  let(:config)    { { "title" => "site title" } }
+  let(:image)     { nil }
+  let(:page_meta) { { "image" => image, "dir" => "foo" } }
+  let(:page)      { make_page(page_meta) }
+  let(:site)      { make_site(config) }
+  let(:context)   { make_context(:page => page, :site => site) }
+  let(:text) { "" }
+  subject { described_class.new(:page => page.to_liquid, :context => context) }
+
+  before do
+    Jekyll.logger.log_level = :error
+  end
+
+  context "with a post object" do
+    let(:image) { "image.png" }
+    let(:page_meta) { { "image" => image, "date" => "2017-01-01" } }
+    let(:page) { make_post(page_meta) }
+
+    it "returns the image url relative to the post directory" do
+      expect(subject["path"]).to eql("/2017/01/01/image.png")
+    end
+  end
+
+  context "with image as a relative path" do
+    let(:image) { "image.png" }
+
+    it "returns the image with the page dir prepended" do
+      expect(subject["path"]).to eql("/foo/image.png")
+    end
+
+    context "with site.url" do
+      let(:config) { { "url" => "http://example.com" } }
+
+      it "makes the path absolute" do
+        expect(subject["path"]).to eql("http://example.com/foo/image.png")
+      end
+    end
+  end
+
+  context "with image as an absolute path" do
+    let(:image) { "/image.png" }
+
+    it "returns the image" do
+      expect(subject["path"]).to eql("/image.png")
+    end
+
+    context "with site.url" do
+      let(:config) { { "url" => "http://example.com" } }
+
+      it "makes the path absolute" do
+        expect(subject["path"]).to eql("http://example.com/image.png")
+      end
+    end
+
+    context "with a URL-escaped path" do
+      let(:image) { "/some image.png" }
+
+      it "URL-escapes the image" do
+        expect(subject["path"]).to eql("/some%20image.png")
+      end
+    end
+  end
+
+  context "with image as a hash" do
+    context "with an absolute path" do
+      let(:image) { { "path" => "/image.png" } }
+
+      it "returns the image" do
+        expect(subject["path"]).to eql("/image.png")
+      end
+    end
+
+    context "with facebook" do
+      let(:image) { { "facebook" => "/image.png" } }
+
+      it "returns the image" do
+        expect(subject["path"]).to eql("/image.png")
+      end
+    end
+
+    context "with twitter" do
+      let(:image) { { "twitter" => "/image.png" } }
+
+      it "returns the image" do
+        expect(subject["path"]).to eql("/image.png")
+      end
+    end
+
+    context "with some random hash" do
+      let(:image) { { "foo" => "bar" } }
+
+      it "returns nil" do
+        expect(subject["path"]).to be_nil
+      end
+
+      it "returns arbitrary values" do
+        expect(subject["foo"]).to eql("bar")
+      end
+    end
+
+    context "with an invalid path" do
+      let(:image) { ":" }
+
+      it "returns the path" do
+        expect(subject["path"]).to eql(":")
+      end
+    end
+
+    context "with height and width" do
+      let(:image) { { "path" => "image.png", "height" => 5, "width" => 10 } }
+
+      it "returns the height and width" do
+        expect(subject["height"]).to eql(5)
+        expect(subject["width"]).to eql(10)
+      end
+    end
+  end
+end

spec/jekyll_seo_tag/json_ld_drop_spec.rb

@@ -1,8 +1,6 @@
-RSpec.describe Jekyll::SeoTag::JSONLD do
-  before do
-    Jekyll.logger.log_level = :error
-  end
+# frozen_string_literal: true
 
+RSpec.describe Jekyll::SeoTag::JSONLDDrop do
   let(:author) { "author" }
   let(:image) { "image" }
   let(:metadata) do
@@ -28,11 +26,16 @@ RSpec.describe Jekyll::SeoTag::JSONLD do
   let(:page)      { make_page(metadata) }
   let(:site)      { make_site(config) }
   let(:context)   { make_context(:page => page, :site => site) }
-  subject { Jekyll::SeoTag::Drop.new("", context).json_ld }
+  let(:page_drop) { Jekyll::SeoTag::Drop.new("", context) }
+  subject { described_class.new(page_drop) }
+
+  before do
+    Jekyll.logger.log_level = :error
+  end
 
   it "returns the context" do
     expect(subject).to have_key("@context")
-    expect(subject["@context"]).to eql("http://schema.org")
+    expect(subject["@context"]).to eql("https://schema.org")
   end
 
   it "returns the type" do
@@ -66,14 +69,52 @@ RSpec.describe Jekyll::SeoTag::JSONLD do
           expect(subject["author"]).to have_key("name")
           expect(subject["author"]["name"]).to be_a(String)
           expect(subject["author"]["name"]).to eql("author")
+          expect(subject["author"]["url"]).to be nil
         end
       end
     end
+
+    context "when type Organization" do
+      let(:author) { { "name" => "organization", "type" => "Organization" } }
+
+      it "returns the author with type" do
+        expect(subject).to have_key("author")
+        expect(subject["author"]).to be_a(Hash)
+        expect(subject["author"]).to have_key("@type")
+        expect(subject["author"]["@type"]).to eql("Organization")
+        expect(subject["author"]).to have_key("name")
+        expect(subject["author"]["name"]).to be_a(String)
+        expect(subject["author"]["name"]).to eql("organization")
+      end
+    end
+
+    context "when invalid type" do
+      let(:author) { { "name" => "organization", "type" => "Invalid" } }
+
+      it "returns the author with type" do
+        expect(subject).to have_key("author")
+        expect(subject["author"]).to be nil
+      end
+    end
+
+    context "when url is present" do
+      let(:author) { { "name" => "author", "url" => "https://example.com" } }
+
+      it "returns the author with url" do
+        expect(subject).to have_key("author")
+        expect(subject["author"]).to be_a(Hash)
+        expect(subject["author"]).to have_key("url")
+        expect(subject["author"]["url"]).to eql("https://example.com")
+        expect(subject["author"]).to have_key("name")
+        expect(subject["author"]["name"]).to be_a(String)
+        expect(subject["author"]["name"]).to eql("author")
+      end
+    end
   end
 
   context "image" do
-    context "with image as a string" do
-      let(:image) { "image" }
+    context "with image as an absolute path" do
+      let(:image) { "/image" }
 
       it "returns the image as a string" do
         expect(subject).to have_key("image")
@@ -83,17 +124,17 @@ RSpec.describe Jekyll::SeoTag::JSONLD do
     end
 
     context "with image as a hash" do
-      let(:image) { { "path" => "image", "height" => 5, "width" => 10 } }
+      let(:image) { { "path" => "/image", "height" => 5, "width" => 10 } }
 
       it "returns the image as a hash" do
         expect(subject).to have_key("image")
         expect(subject["image"]).to be_a(Hash)
-        expect(subject["image"]).to eql({
+        expect(subject["image"]).to eql(
           "@type"  => "imageObject",
           "url"    => "/image",
           "height" => 5,
-          "width"  => 10,
-        })
+          "width"  => 10
+        )
       end
     end
   end
@@ -150,21 +191,11 @@ RSpec.describe Jekyll::SeoTag::JSONLD do
     expect(subject["url"]).to eql("/page.html")
   end
 
-  context "validating" do
-    let(:html) do
-      "<script type=\"application/ld+json\">#{subject.to_json}</script>"
-    end
-    let(:image) { { "path" => "image", "height" => "100%", "width" => "10px" } }
-    let(:config) do
-      {
-        "logo"     => "logo",
-        "timezone" => "America/New_York",
-        "url"      => "http://example.com",
-      }
-    end
+  context "with null values" do
+    let(:metadata) { {} }
 
-    it "validates" do
-      expect(html).to be_valid_json_ld
+    it "does not return null values as json" do
+      expect(subject.to_json).to_not match(%r!:null!)
     end
   end
 end

spec/jekyll_seo_tag_integration_spec.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 RSpec.describe Jekyll::SeoTag do
   let(:page)      { make_page }
   let(:site)      { make_site }
@@ -6,7 +8,7 @@ RSpec.describe Jekyll::SeoTag do
   let(:tag)       { "seo" }
   let(:text)      { "" }
   let(:output)    { Liquid::Template.parse("{% #{tag} #{text} %}").render!(context, {}) }
-  let(:json)      { output.match(%r!<script type=\"application/ld\+json\">(.*)</script>!m)[1] }
+  let(:json)      { output.match(%r!<script type="application/ld\+json">(.*)</script>!m)[1] }
   let(:json_data) { JSON.parse(json) }
   let(:paginator) { { "previous_page" => true, "previous_page_path" => "foo", "next_page" => true, "next_page_path" => "bar" } }
 
@@ -23,6 +25,15 @@ RSpec.describe Jekyll::SeoTag do
     expect(output).to match(%r!Jekyll SEO tag v#{version}!i)
   end
 
+  it "outputs meta generator" do
+    version = Jekyll::VERSION
+    expect(output).to match(%r!Jekyll v#{version}!i)
+  end
+
+  it "outputs JSON sorted by key" do
+    expect(json.strip).to eql('{"@context":"https://schema.org","@type":"WebPage","url":"/page.html"}')
+  end
+
   it "outputs valid HTML" do
     site.process
     options = {
@@ -113,6 +124,7 @@ RSpec.describe Jekyll::SeoTag do
     it "uses the page description" do
       expect(output).to match(%r!<meta name="description" content="foo" />!)
       expect(output).to match(%r!<meta property="og:description" content="foo" />!)
+      expect(output).to match(%r!<meta property="twitter:description" content="foo" />!)
     end
   end
 
@@ -122,6 +134,7 @@ RSpec.describe Jekyll::SeoTag do
     it "uses the page excerpt when no page description exists" do
       expect(output).to match(%r!<meta name="description" content="foo" />!)
       expect(output).to match(%r!<meta property="og:description" content="foo" />!)
+      expect(output).to match(%r!<meta property="twitter:description" content="foo" />!)
     end
   end
 
@@ -131,6 +144,7 @@ RSpec.describe Jekyll::SeoTag do
     it "uses the site description when no page description nor excerpt exist" do
       expect(output).to match(%r!<meta name="description" content="foo" />!)
       expect(output).to match(%r!<meta property="og:description" content="foo" />!)
+      expect(output).to match(%r!<meta property="twitter:description" content="foo" />!)
     end
   end
 
@@ -293,15 +307,16 @@ RSpec.describe Jekyll::SeoTag do
 
       it "minifies the output" do
         version = Jekyll::SeoTag::VERSION
-        expected = <<-EOS
-<!-- Begin Jekyll SEO tag v#{version} -->
-<title>Foo</title>
-<meta property="og:title" content="Foo" />
-<meta property="og:locale" content="en_US" />
-<link rel="canonical" href="http://example.invalid/page.html" />
-<meta property="og:url" content="http://example.invalid/page.html" />
-<meta property="og:site_name" content="Foo" />
-EOS
+        expected = <<~HTML
+          <!-- Begin Jekyll SEO tag v#{version} -->
+          <title>Foo</title>
+          <meta name="generator" content="Jekyll v#{Jekyll::VERSION}" />
+          <meta property="og:title" content="Foo" />
+          <meta property="og:locale" content="en_US" />
+          <link rel="canonical" href="http://example.invalid/page.html" />
+          <meta property="og:url" content="http://example.invalid/page.html" />
+          <meta property="og:site_name" content="Foo" />
+        HTML
         expect(output).to match(expected)
       end
     end
@@ -329,10 +344,28 @@ EOS
       end
 
       it "minifies JSON-LD" do
-        expected = <<-EOS.strip
-{"@context":"http://schema.org","@type":"BlogPosting","headline":"post",
-EOS
-        expect(output).to match(expected)
+        expect(output).to_not match(%r!{.*?\s.*?}!)
+      end
+
+      it "removes null values from JSON-LD" do
+        expect(output).to_not match(%r!:null!)
+      end
+
+      context "description" do
+        context "with page.seo_description_max_words" do
+          let(:meta) do
+            {
+              "title"                     => "post",
+              "description"               => "For a long time, I went to bed early",
+              "image"                     => "/img.png",
+              "seo_description_max_words" => 6,
+            }
+          end
+
+          it "truncates the description" do
+            expect(json_data["description"]).to eql("For a long time, I went…")
+          end
+        end
       end
     end
   end
@@ -416,11 +449,34 @@ EOS
       end
 
       context "with page.image" do
-        let(:page) { make_page("image" => "/img/foo.png") }
+        context "without *.twitter.card" do
+          let(:page) { make_page("image" => "/img/foo.png") }
 
-        it "outputs summary card with large image" do
-          expected = %r!<meta name="twitter:card" content="summary_large_image" />!
-          expect(output).to match(expected)
+          it "outputs summary card with large image" do
+            expected = %r!<meta name="twitter:card" content="summary_large_image" />!
+            expect(output).to match(expected)
+          end
+        end
+
+        context "with page.twitter.card" do
+          let(:page_twitter) { { "card" => "summary" } }
+          let(:page) { make_page("image" => "/img/foo.png", "twitter" => page_twitter) }
+
+          it "outputs summary card with small image" do
+            expected = %r!<meta name="twitter:card" content="summary" />!
+            expect(output).to match(expected)
+          end
+        end
+
+        context "with site.twitter.card" do
+          let(:site_twitter) { { "username" => "jekyllrb", "card" => "summary" } }
+          let(:site) { make_site("twitter" => site_twitter) }
+          let(:page) { make_page("image" => "/img/foo.png") }
+
+          it "outputs summary card with small image" do
+            expected = %r!<meta name="twitter:card" content="summary" />!
+            expect(output).to match(expected)
+          end
         end
       end
 
@@ -573,8 +629,8 @@ EOS
     let(:context) { make_context({}, "paginator" => paginator) }
 
     it "outputs pagination links" do
-      expect(output).to match(%r!<link rel="prev" href="/foo">!)
-      expect(output).to match(%r!<link rel="next" href="/bar">!)
+      expect(output).to match(%r!<link rel="prev" href="/foo" />!)
+      expect(output).to match(%r!<link rel="next" href="/bar" />!)
     end
   end
 
@@ -582,32 +638,38 @@ EOS
     context "with site.webmaster_verifications" do
       let(:site_verifications) do
         {
-          "google" => "foo",
-          "bing"   => "bar",
-          "alexa"  => "baz",
-          "yandex" => "bat",
+          "google"   => "foo",
+          "bing"     => "bar",
+          "alexa"    => "baz",
+          "yandex"   => "bat",
+          "facebook" => "bas",
         }
       end
 
       let(:site) { make_site("webmaster_verifications" => site_verifications) }
 
       it "outputs google verification meta" do
-        expected = %r!<meta name="google-site-verification" content="foo">!
+        expected = %r!<meta name="google-site-verification" content="foo" />!
         expect(output).to match(expected)
       end
 
       it "outputs bing verification meta" do
-        expected = %r!<meta name="msvalidate.01" content="bar">!
+        expected = %r!<meta name="msvalidate.01" content="bar" />!
         expect(output).to match(expected)
       end
 
       it "outputs alexa verification meta" do
-        expected = %r!<meta name="alexaVerifyID" content="baz">!
+        expected = %r!<meta name="alexaVerifyID" content="baz" />!
         expect(output).to match(expected)
       end
 
       it "outputs yandex verification meta" do
-        expected = %r!<meta name="yandex-verification" content="bat">!
+        expected = %r!<meta name="yandex-verification" content="bat" />!
+        expect(output).to match(expected)
+      end
+
+      it "outputs facebook verification meta" do
+        expected = %r!<meta name="facebook-domain-verification" content="bas" />!
         expect(output).to match(expected)
       end
     end
@@ -629,10 +691,10 @@ EOS
     end
 
     context "with site.lang" do
-      let(:site)  { make_site("lang" => "en_US") }
+      let(:site)  { make_site("lang" => "de_DE") }
 
       it "uses site.lang if page.lang is not present" do
-        expected = %r!<meta property="og:locale" content="en_US" />!
+        expected = %r!<meta property="og:locale" content="de_DE" />!
         expect(output).to match(expected)
       end
 
@@ -647,10 +709,10 @@ EOS
     end
 
     context "with site.lang hyphenated" do
-      let(:site)  { make_site("lang" => "en-US") }
+      let(:site)  { make_site("lang" => "en-AU") }
 
       it "coerces hyphen to underscore" do
-        expected = %r!<meta property="og:locale" content="en_US" />!
+        expected = %r!<meta property="og:locale" content="en_AU" />!
         expect(output).to match(expected)
       end
     end

spec/jekyll_seo_tag_spec.rb

@@ -0,0 +1,52 @@
+# frozen_string_literal: true
+
+RSpec.describe Jekyll::SeoTag do
+  let(:config)    { { "title" => "site title" } }
+  let(:page_meta) { {} }
+  let(:page)      { make_page(page_meta) }
+  let(:site)      { make_site(config) }
+  let(:render_context) { make_context(:page => page, :site => site) }
+  let(:text) { "" }
+  let(:tag_name) { "github_edit_link" }
+  let(:tokenizer) { Liquid::Tokenizer.new("") }
+  let(:parse_context) { Liquid::ParseContext.new }
+  let(:rendered) { subject.render(render_context) }
+  let(:payload) { subject.send(:payload) }
+
+  subject do
+    tag = described_class.parse(tag_name, text, tokenizer, parse_context)
+    tag.instance_variable_set("@context", render_context)
+    tag
+  end
+
+  before do
+    Jekyll.logger.log_level = :error
+  end
+
+  it "returns the template" do
+    expect(described_class.template).to be_a(Liquid::Template)
+  end
+
+  context "payload" do
+    it "contains the drop" do
+      expect(payload["seo_tag"]).to be_a(Jekyll::SeoTag::Drop)
+    end
+
+    it "contains the Jekyll drop" do
+      expect(payload["jekyll"]).to be_a(Jekyll::Drops::JekyllDrop)
+    end
+
+    it "contains the page" do
+      expect(payload["page"]).to be_a(Jekyll::Page)
+    end
+
+    it "contains the site" do
+      expect(payload["site"]).to be_a(Jekyll::Drops::SiteDrop)
+    end
+  end
+
+  it "renders" do
+    expected = "<!-- Begin Jekyll SEO tag v#{described_class::VERSION} -->"
+    expect(rendered).to match(expected)
+  end
+end

spec/spec_helper.rb

@@ -1,38 +1,27 @@
-$LOAD_PATH.unshift File.expand_path("../../lib", __FILE__)
+# frozen_string_literal: true
+
+$LOAD_PATH.unshift File.expand_path("../lib", __dir__)
 require "jekyll"
 require "jekyll-seo-tag"
 require "html-proofer"
-require "uri"
-require "net/http"
+
+# Monkey patch Jekyll::Drops::Drop so Rspec's `have_key` works as expected
+module Jekyll
+  module Drops
+    class Drop
+      alias_method :has_key?, :key?
+    end
+  end
+end
 
 ENV["JEKYLL_LOG_LEVEL"] = "error"
 
-RSpec::Matchers.define :be_valid_json_ld do |_expected|
-  match do |actual|
-    validate_json_ld(actual)["errors"].empty?
-  end
-
-  failure_message do |actual|
-    validate_json_ld(actual)["errors"]
-  end
-
-  def validate_json_ld(html)
-    params = { "html" => html }
-    url = URI.parse("https://search.google.com/structured-data/testing-tool/validate")
-    response = Net::HTTP.post_form(url, params)
-    JSON.parse(response.body.split("\n")[1])
-  rescue
-    puts "Unable to validate JSON"
-    { "errors" => [] }
-  end
-end
-
 def dest_dir
-  File.expand_path("../tmp/dest", File.dirname(__FILE__))
+  File.expand_path("../tmp/dest", __dir__)
 end
 
 def source_dir
-  File.expand_path("./fixtures", File.dirname(__FILE__))
+  File.expand_path("fixtures", __dir__)
 end
 
 CONFIG_DEFAULTS = {
@@ -42,7 +31,7 @@ CONFIG_DEFAULTS = {
 }.freeze
 
 def make_page(options = {})
-  page = Jekyll::Page.new site, CONFIG_DEFAULTS["source"], "", "page.md"
+  page = Jekyll::Page.new site, CONFIG_DEFAULTS["source"], options.delete("dir") || "", "page.md"
   page.data = options
   page
 end