80 lines
3.0 KiB
Markdown
80 lines
3.0 KiB
Markdown
[](https://www.npmjs.org/package/stream-connect)
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[](https://www.npmjs.org/package/stream-connect)
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[](https://travis-ci.org/75lb/stream-connect)
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[](https://coveralls.io/github/75lb/stream-connect?branch=master)
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[](https://david-dm.org/75lb/stream-connect)
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[](https://github.com/feross/standard)
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# stream-connect
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Similar to `.pipe` except `.pipe` returns the last stream in a pipeline. stream-connect returns a stream which writes to the first stream in the pipeline and reads from the last.
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## Synopsis
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```js
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const connect = require('stream-connect')
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const fs = require('fs')
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const connected = connect(stream1, stream2, stream3, stream4)
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// data piped into the connected stream is transparently passed through all four internal streams
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// then output into process.stdout. Errors in any of the internal streams are emitted
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// by the connected stream.
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process.stdin
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.pipe(connected)
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.on('error', console.error)
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.pipe(process.stdout)
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```
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## More detail
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Consider this `.pipe` example.
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```js
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function getExampleStream () {
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...
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return streamOne.pipe(streamTwo)
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}
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const stream = getExampleStream()
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stream.on('data', function (chunk) {}) // catches data from streamOne via streamTwo
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stream.on('error', function (err) {}) // catches errors only from streamTwo
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stream.end('test') // is written to streamTwo
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```
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If you write to the output it will be written to `streamTwo`, whereas you probably wanted to write to the start of the pipeline and read from the end. Fixed by stream-connect:
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```js
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const connect = require('stream-connect')
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function getExampleStream () {
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...
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return connect(streamOne, streamTwo)
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}
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const stream = getExampleStream()
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stream.on('data', function (chunk) {}) // catches data from streamOne via streamTwo
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stream.on('error', function (err) {}) // catches errors from both streamOne and streamTwo
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stream.end('test') // is written to streamOne
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```
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Any errors emitted in `streamOne` or `streamTwo` are propagated to the output stream.
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<a name="module_stream-connect"></a>
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## stream-connect
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**Example**
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```js
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const connect = require('stream-connect')
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```
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<a name="exp_module_stream-connect--connect"></a>
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### connect(...streams) ⇒ <code>[Duplex](https://nodejs.org/api/stream.html#stream_class_stream_duplex)</code> ⏏
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Connect streams.
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**Kind**: Exported function
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| Param | Type | Description |
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| --- | --- | --- |
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| ...streams | <code>[Duplex](https://nodejs.org/api/stream.html#stream_class_stream_duplex)</code> | One or more streams to connect. |
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* * *
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© 2015 Lloyd Brookes \<75pound@gmail.com\>. Documented by [jsdoc-to-markdown](https://github.com/jsdoc2md/jsdoc-to-markdown).
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