forked from zhurui/management
103 lines
2.7 KiB
Markdown
103 lines
2.7 KiB
Markdown
# multipipe
|
|
|
|
A better `Stream#pipe` that creates duplex streams and lets you handle errors in one place.
|
|
|
|
[](http://travis-ci.org/segmentio/multipipe)
|
|
|
|
## Example
|
|
|
|
```js
|
|
var pipe = require('multipipe');
|
|
|
|
// pipe streams
|
|
var stream = pipe(streamA, streamB, streamC);
|
|
|
|
// centralized error handling
|
|
stream.on('error', fn);
|
|
|
|
// creates a new stream
|
|
source.pipe(stream).pipe(dest);
|
|
|
|
// optional callback on finish or error
|
|
pipe(streamA, streamB, streamC, function(err){
|
|
// ...
|
|
});
|
|
```
|
|
|
|
## Duplex streams
|
|
|
|
Write to the pipe and you'll really write to the first stream, read from the pipe and you'll read from the last stream.
|
|
|
|
```js
|
|
var stream = pipe(a, b, c);
|
|
|
|
source
|
|
.pipe(stream)
|
|
.pipe(destination);
|
|
```
|
|
|
|
In this example the flow of data is:
|
|
|
|
* source ->
|
|
* a ->
|
|
* b ->
|
|
* c ->
|
|
* destination
|
|
|
|
## Error handling
|
|
|
|
Each `pipe` forwards the errors the streams it wraps emit, so you have one central place to handle errors:
|
|
|
|
```js
|
|
var stream = pipe(a, b, c);
|
|
|
|
stream.on('error', function(err){
|
|
// called three times
|
|
});
|
|
|
|
a.emit('error', new Error);
|
|
b.emit('error', new Error);
|
|
c.emit('error', new Error);
|
|
```
|
|
|
|
## API
|
|
|
|
### pipe(stream, ...)
|
|
|
|
Pass a variable number of streams and each will be piped to the next one.
|
|
|
|
A stream will be returned that wraps passed in streams in a way that errors will be forwarded and you can write to and/or read from it.
|
|
|
|
Pass a function as last argument to be called on `error` or `finish` of the last stream.
|
|
|
|
## Installation
|
|
|
|
```bash
|
|
$ npm install multipipe
|
|
```
|
|
|
|
## License
|
|
|
|
The MIT License (MIT)
|
|
|
|
Copyright (c) 2014 Segment.io Inc. <friends@segment.io>
|
|
Copyright (c) 2014 Julian Gruber <julian@juliangruber.com>
|
|
|
|
Permission is hereby granted, free of charge, to any person obtaining a copy
|
|
of this software and associated documentation files (the "Software"), to deal
|
|
in the Software without restriction, including without limitation the rights
|
|
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
|
|
copies of the Software, and to permit persons to whom the Software is
|
|
furnished to do so, subject to the following conditions:
|
|
|
|
The above copyright notice and this permission notice shall be included in
|
|
all copies or substantial portions of the Software.
|
|
|
|
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
|
|
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
|
|
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
|
|
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
|
|
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
|
|
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
|
|
THE SOFTWARE.
|