47 lines
1.7 KiB
Markdown
47 lines
1.7 KiB
Markdown
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# minipass
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A _very_ minimal implementation of a [PassThrough
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stream](https://nodejs.org/api/stream.html#stream_class_stream_passthrough)
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[It's very
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fast](https://docs.google.com/spreadsheets/d/1oObKSrVwLX_7Ut4Z6g3fZW-AX1j1-k6w-cDsrkaSbHM/edit#gid=0)
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for objects, strings, and buffers.
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Supports pipe()ing (including multi-pipe() and backpressure
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transmission), buffering data until either a `data` event handler or
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`pipe()` is added (so you don't lose the first chunk), and most other
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cases where PassThrough is a good idea.
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There is a `read()` method, but it's much more efficient to consume
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data from this stream via `'data'` events or by calling `pipe()` into
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some other stream. Calling `read()` requires the buffer to be
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flattened in some cases, which requires copying memory. Also,
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`read()` always returns Buffers, even if an `encoding` option is
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specified.
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There is also no `unpipe()` method. Once you start piping, there is
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no stopping it!
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If you set `objectMode: true` in the options, then whatever is written
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will be emitted. Otherwise, it'll do a minimal amount of Buffer
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copying to ensure proper Streams semantics when `read(n)` is called.
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This is not a `through` or `through2` stream. It doesn't transform
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the data, it just passes it right through. If you want to transform
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the data, extend the class, and override the `write()` method. Once
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you're done transforming the data however you want, call
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`super.write()` with the transform output.
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For an example of a stream that extends MiniPass to provide transform
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capabilities, check out [minizlib](http://npm.im/minizlib).
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## USAGE
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```js
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const MiniPass = require('minipass')
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const mp = new MiniPass(options) // optional: { encoding }
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mp.write('foo')
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mp.pipe(someOtherStream)
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mp.end('bar')
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```
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