Streams
Makes it easy to use various types of streams by giving a simple interfacing
and allowing specification of their actions by passing a function.
Whats the Use?
Use several types of streams (transform, read, write, counter) with minimal configuration or syntax. Just need input and functions to define transformations and output.
installation
npm install @jadesrochers/streams
const streams = require('@jadesrochers/streams')
Usage
Four stream types are provided; read, transform, count, and write.
The count stream is just a custom transform stream for tracking
how many object passed through the stream.
Set up transform and write functions.
let transfcn = n => (parseInt(n) + 1)
let writefcn = n => console.log(n) Create the stream objects, demonstrating all of them here.
let reader = streams.fileStream('./testfile.txt')
let transform = streams.transformStream(transfcn)
let counter = streams.countStream(10, ' stream objects')
let writer = streams.writeStream(writefcn) Using the split library so that the test file is broken into lines.
const split = require('split2');Create the test file
testfile.txt; put it in the directory you will run node from.
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Read the data and run it through the streams
reader.pipe(split()).pipe(transform).pipe(counter).pipe(writer).on('finish', () => { console.log('Stream complete, closed'); process.exit(0)}).on('error', () => console.log('Somthing went wrong'))