hatuhn f14a34ba19 uapte

2019-09-13 09:44:33 +07:00

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StreamQueue

StreamQueue pipe the queued streams one by one in order to preserve their content order.

## Usage Install the npm module:

npm install streamqueue --save

Then, in your scripts:

var streamqueue = require('streamqueue');

var queue = streamqueue(
  Fs.createReadStream('input.txt'),
  Fs.createReadStream('input2.txt'),
  Fs.createReadStream('input3.txt')
).pipe(process.stdout);

StreamQueue also accept functions returning streams, the above can be written like this, doing system calls only when piping:

var streamqueue = require('streamqueue');

var queue = streamqueue(
  Fs.createReadStream.bind(null, 'input.txt'),
  Fs.createReadStream.bind(null, 'input2.txt'),
  Fs.createReadStream.bind(null, 'input3.txt')
).pipe(process.stdout);

Object-oriented traditionnal API offers more flexibility:

var StreamQueue = require('streamqueue');

var queue = new StreamQueue();
queue.queue(
  Fs.createReadStream('input.txt'),
  Fs.createReadStream('input2.txt'),
  Fs.createReadStream('input3.txt')
);
queue.done();

queue.pipe(process.stdout);

You can also chain StreamQueue methods like that:

var StreamQueue = require('streamqueue');

new StreamQueue()
  .queue(Fs.createReadStream('input.txt'))
  .queue(Fs.createReadStream('input2.txt'))
  .queue(Fs.createReadStream('input3.txt'))
  .done()
  .pipe(process.stdout);

You can queue new streams at any moment until you call the done() method. So the created stream will not fire the end event until done() call.

Note that stream queue is compatible with the Node 0.10+ streams. For older streams, stream queue will wrap them with Readable.wrap before queueing. Please fix your dependencies or report issues to libraries using 0.8 streams since this extra code will finally be removed.

API

StreamQueue([options], [stream1, stream2, ... streamN])

options

options.objectMode

Type: Boolean Default value: false

Use if piped in streams are in object mode. In this case, the stream queue will also be in the object mode.

options.pauseFlowingStream

Type: Boolean Default value: true

If a stream is in flowing mode, then it will be paused before queueing.

options.resumeFlowingStream

Type: Boolean Default value: true

If a stream is in flowing mode, then it will be resumed before piping.

options.*

StreamQueue inherits of Stream.PassThrough, the options are passed to the parent constructor so you can use it's options too.

streamN

Type: Stream

Append streams given in argument to the queue and ends when the queue is empty.

StreamQueue.queue(stream1, [stream2, ... streamN])

Append streams given in argument to the queue.

StreamQueue.done([stream1, stream2, ... streamN])