collect-transform-stream
v0.0.2
Published
create a transform stream that runs a function over all collected elements
Downloads
23
Readme
collect-transform-stream
create a transform stream that runs a function over all collected elements
Sometimes you end up in a situation where you have a stream pipeline like
pump(source, transform, destination)
but you have another transform function that needs to process all elements in the stream before passing them on, e.g. filtering duplicates from an unordered stream:
pump(source, collectAndFilter, transform, destination)
collect-transform-stream
is a tiny module that provides this.
Usage
var uniq = require('uniq')
var from = require('from2')
var collect = require('concat-stream')
var collectTransform = require('collect-transform-stream')
var source = from.obj(new Array(500).fill(0).map(function () {
return Math.floor(Math.random() * 10)
}))
var dedupe = collectTransform(function (nums) {
return uniq(nums)
})
var dest = collect({encoding:'object'}, console.log)
source.pipe(dedupe).pipe(dest)
outputs
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API
var collect = require('collect-transform-stream')
collect(fn[, cb])
Create a Transform stream that runs the function fn
on all incoming objects at
once, then pipes elements individually onward to the next stream in the
pipeline.
Use return result
to use synchronously; call cb(err, result)
to use
asynchronously.
Install
With npm installed, run
$ npm install collect-transform-stream
License
ISC