katoikia-app/web-ui/web-react/node_modules/http-proxy-middleware/lib/handlers.js

83 lines
2.0 KiB
JavaScript

var _ = require('lodash')
var logger = require('./logger').getInstance()
module.exports = {
init: init,
getHandlers: getProxyEventHandlers
}
function init(proxy, opts) {
var handlers = getProxyEventHandlers(opts)
_.forIn(handlers, function(handler, eventName) {
proxy.on(eventName, handlers[eventName])
})
logger.debug('[HPM] Subscribed to http-proxy events: ', _.keys(handlers))
}
function getProxyEventHandlers(opts) {
// https://github.com/nodejitsu/node-http-proxy#listening-for-proxy-events
var proxyEvents = [
'error',
'proxyReq',
'proxyReqWs',
'proxyRes',
'open',
'close'
]
var handlers = {}
_.forEach(proxyEvents, function(event) {
// all handlers for the http-proxy events are prefixed with 'on'.
// loop through options and try to find these handlers
// and add them to the handlers object for subscription in init().
var eventName = _.camelCase('on ' + event)
var fnHandler = _.get(opts, eventName)
if (_.isFunction(fnHandler)) {
handlers[event] = fnHandler
}
})
// add default error handler in absence of error handler
if (!_.isFunction(handlers.error)) {
handlers.error = defaultErrorHandler
}
// add default close handler in absence of close handler
if (!_.isFunction(handlers.close)) {
handlers.close = logClose
}
return handlers
}
function defaultErrorHandler(err, req, res) {
var host = req.headers && req.headers.host
var code = err.code
if (res.writeHead && !res.headersSent) {
if (/HPE_INVALID/.test(code)) {
res.writeHead(502)
} else {
switch (code) {
case 'ECONNRESET':
case 'ENOTFOUND':
case 'ECONNREFUSED':
res.writeHead(504)
break
default:
res.writeHead(500)
}
}
}
res.end('Error occured while trying to proxy to: ' + host + req.url)
}
function logClose(req, socket, head) {
// view disconnected websocket connections
logger.info('[HPM] Client disconnected')
}