45 lines
1.8 KiB
Markdown
45 lines
1.8 KiB
Markdown
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# minizlib
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A tiny fast zlib stream built on [minipass](http://npm.im/minipass)
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and Node.js's zlib binding.
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This module was created to serve the needs of
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[node-tar](http://npm.im/tar) v2. If your needs are different, then
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it may not be for you.
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## How does this differ from the streams in `require('zlib')`?
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First, there are no convenience methods to compress or decompress a
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buffer. If you want those, use the built-in `zlib` module. This is
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only streams.
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This module compresses and decompresses the data as fast as you feed
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it in. It is synchronous, and runs on the main process thread. Zlib
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operations can be high CPU, but they're very fast, and doing it this
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way means much less bookkeeping and artificial deferral.
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Node's built in zlib streams are built on top of `stream.Transform`.
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They do the maximally safe thing with respect to consistent
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asynchrony, buffering, and backpressure.
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This module _does_ support backpressure, and will buffer output chunks
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that are not consumed, but is less of a mediator between the input and
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output. There is no high or low watermarks, no state objects, and so
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artificial async deferrals. It will not protect you from Zalgo.
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If you write, data will be emitted right away. If you write
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everything synchronously in one tick, and you are listening to the
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`data` event to consume it, then it'll all be emitted right away in
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that same tick. If you want data to be emitted in the next tick, then
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write it in the next tick.
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It is thus the responsibility of the reader and writer to manage their
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own consumption and process execution flow.
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The goal is to compress and decompress as fast as possible, even for
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files that are too large to store all in one buffer.
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The API is very similar to the built-in zlib module. There are
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classes that you instantiate with `new` and they are streams that can
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be piped together.
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