mirror of https://github.com/jkjoy/sunpeiwen.git
48 lines
1.2 KiB
Markdown
48 lines
1.2 KiB
Markdown
# minipass-flush
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A Minipass stream that calls a flush function before emitting 'end'
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## USAGE
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```js
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const Flush = require('minipass-flush')
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cons f = new Flush({
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flush (cb) {
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// call the cb when done, or return a promise
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// the 'end' event will wait for it, along with
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// close, finish, and prefinish.
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// call the cb with an error, or return a rejecting
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// promise to emit 'error' instead of doing the 'end'
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return rerouteAllEncryptions().then(() => clearAllChannels())
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},
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// all other minipass options accepted as well
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})
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someDataSource.pipe(f).on('end', () => {
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// proper flushing has been accomplished
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})
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// Or as a subclass implementing a 'flush' method:
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class MyFlush extends Flush {
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flush (cb) {
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// old fashioned callback style!
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rerouteAllEncryptions(er => {
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if (er)
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return cb(er)
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clearAllChannels(er => {
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if (er)
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cb(er)
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cb()
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})
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})
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}
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}
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```
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That's about it.
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If your `flush` method doesn't have to do anything asynchronous, then it's
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better to call the callback right away in this tick, rather than returning
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`Promise.resolve()`, so that the `end` event can happen as soon as
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possible.
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