transform-stream-backpressure

Transform-stream-backpressure

A transform stream that applies backpressure based on a check function.

Purpose

Creates a pass through stream where backpressure is governed by the provided check() function.

Usage

const fs = require('fs');

function check () {
  return new Promise((resolve) => {
    setTimeout(500, resolve);
  });
}

const readable = fs.createReadStream('myfile');
const writable = fs.createWriteStream('other');

const transform = require('transform-stream-backpressure')(myfunc, { objectMode: true, highWaterMark: 20 });
readable.pipe(transform).pipe(writable);

API

Creates a transform stream with backpressure governed by the check() function. ⇒ Transform

Returns: Transform - A transform stream.

Param	Type	Description
check	function	function that returns a promise. If it resolves to truthy, chunk is passed through.
config	object	general stream config passed to new Transform().

Note: To regenerate this section from the jsdoc run npm run docs and paste the output above.

Installation

This module is installed via npm:

$ npm install transform-stream-backpressure

License

The BSD License

Copyright (c) 2018, Tim Allen

All rights reserved.

Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met:

• Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer.

• Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution.

• Neither the name of the Tim Allen nor the names of its contributors may be used to endorse or promote products derived from this software without specific prior written permission.

THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.