71 lines
2.4 KiB
Markdown
71 lines
2.4 KiB
Markdown
|
# fs-minipass
|
||
|
|
|
||
|
|
Filesystem streams based on [minipass](http://npm.im/minipass).
|
||
|
|
|
||
|
|
4 classes are exported:
|
||
|
|
|
||
|
|
- ReadStream
|
||
|
|
- ReadStreamSync
|
||
|
|
- WriteStream
|
||
|
|
- WriteStreamSync
|
||
|
|
|
||
|
|
When using `ReadStreamSync`, all of the data is made available
|
||
|
|
immediately upon consuming the stream. Nothing is buffered in memory
|
||
|
|
when the stream is constructed. If the stream is piped to a writer,
|
||
|
|
then it will synchronously `read()` and emit data into the writer as
|
||
|
|
fast as the writer can consume it. (That is, it will respect
|
||
|
|
backpressure.) If you call `stream.read()` then it will read the
|
||
|
|
entire file and return the contents.
|
||
|
|
|
||
|
|
When using `WriteStreamSync`, every write is flushed to the file
|
||
|
|
synchronously. If your writes all come in a single tick, then it'll
|
||
|
|
write it all out in a single tick. It's as synchronous as you are.
|
||
|
|
|
||
|
|
The async versions work much like their node builtin counterparts,
|
||
|
|
with the exception of introducing significantly less Stream machinery
|
||
|
|
overhead.
|
||
|
|
|
||
|
|
## USAGE
|
||
|
|
|
||
|
|
It's just streams, you pipe them or read() them or write() to them.
|
||
|
|
|
||
|
|
```js
|
||
|
|
const fsm = require('fs-minipass')
|
||
|
|
const readStream = new fsm.ReadStream('file.txt')
|
||
|
|
const writeStream = new fsm.WriteStream('output.txt')
|
||
|
|
writeStream.write('some file header or whatever\n')
|
||
|
|
readStream.pipe(writeStream)
|
||
|
|
```
|
||
|
|
|
||
|
|
## ReadStream(path, options)
|
||
|
|
|
||
|
|
Path string is required, but somewhat irrelevant if an open file
|
||
|
|
descriptor is passed in as an option.
|
||
|
|
|
||
|
|
Options:
|
||
|
|
|
||
|
|
- `fd` Pass in a numeric file descriptor, if the file is already open.
|
||
|
|
- `readSize` The size of reads to do, defaults to 16MB
|
||
|
|
- `size` The size of the file, if known. Prevents zero-byte read()
|
||
|
|
call at the end.
|
||
|
|
- `autoClose` Set to `false` to prevent the file descriptor from being
|
||
|
|
closed when the file is done being read.
|
||
|
|
|
||
|
|
## WriteStream(path, options)
|
||
|
|
|
||
|
|
Path string is required, but somewhat irrelevant if an open file
|
||
|
|
descriptor is passed in as an option.
|
||
|
|
|
||
|
|
Options:
|
||
|
|
|
||
|
|
- `fd` Pass in a numeric file descriptor, if the file is already open.
|
||
|
|
- `mode` The mode to create the file with. Defaults to `0o666`.
|
||
|
|
- `start` The position in the file to start reading. If not
|
||
|
|
specified, then the file will start writing at position zero, and be
|
||
|
|
truncated by default.
|
||
|
|
- `autoClose` Set to `false` to prevent the file descriptor from being
|
||
|
|
closed when the stream is ended.
|
||
|
|
- `flags` Flags to use when opening the file. Irrelevant if `fd` is
|
||
|
|
passed in, since file won't be opened in that case. Defaults to
|
||
|
|
`'a'` if a `pos` is specified, or `'w'` otherwise.
|