stream-to-it

Convert Node.js streams to streaming iterables

About

Seamlessly use Node.js streams with it-pipe and friends.

Example - Convert readable stream to source iterable

1import fs from 'node:fs'
2import * as toIterable from 'stream-to-it'
3
4const readable = fs.createReadStream('/path/to/file')
5// Node.js streams are already async iterable so this is just s => s
6const source = toIterable.source<Buffer>(readable)
7
8for await (const chunk of source) {
9  console.log(chunk.toString())
10}

Also works with browser ReadableStream:

1import * as toIterable from 'stream-to-it'
2
3const res = await fetch('http://example.org/file.jpg')
4
5if (res.body == null) {
6  throw new Error('Body was not set')
7}
8
9for await (const chunk of toIterable.source(res.body)) {
10  console.log(chunk.toString())
11}

Example - Convert writable stream to sink iterable

1import fs from 'node:fs'
2import { pipe } from 'it-pipe'
3import * as toIterable from 'stream-to-it'
4
5const source = [Buffer.from('Hello '), Buffer.from('World!')]
6const sink = toIterable.sink(fs.createWriteStream('/path/to/file'))
7
8await pipe(source, sink)

Example - Convert transform stream to transform iterable

1import fs from 'node:fs'
2import { Transform } from 'node:stream'
3import { pipe } from 'it-pipe'
4import * as toIterable from 'stream-to-it'
5
6const output = await pipe(
7  [true, false, true, true],
8  toIterable.transform(new Transform({ // Inverter transform :)
9    transform (chunk, enc, cb) {
10      cb(null, !chunk)
11    }
12  })),
13  // Collect and return the chunks
14  async source => {
15    const chunks = []
16    for await (const chunk of source) chunks.push(chunk)
17    return chunks
18  }
19)
20
21console.log(output) // [ false, true, false, false ]

Related

• it-to-stream Convert streaming iterables to Node.js streams
• it-pipe Utility to "pipe" async iterables together

Install

1$ npm i stream-to-it

API Docs

• https://alanshaw.github.io/stream-to-it

License

Licensed under either of

• Apache 2.0, (LICENSE-APACHE / http://www.apache.org/licenses/LICENSE-2.0)
• MIT (LICENSE-MIT / http://opensource.org/licenses/MIT)

Contribution

Unless you explicitly state otherwise, any contribution intentionally submitted for inclusion in the work by you, as defined in the Apache-2.0 license, shall be dual licensed as above, without any additional terms or conditions.