isstream

isStream

Test if an object is a Stream

The missing Stream.isStream(obj): determine if an object is standard Node.js Stream. Works for Node-core Stream objects (for 0.8, 0.10, 0.11, and in theory, older and newer versions) and all versions of readable-stream.

Usage:

var isStream = require('isstream')
var Stream = require('stream')

isStream(new Stream()) // true

isStream({}) // false

isStream(new Stream.Readable())    // true
isStream(new Stream.Writable())    // true
isStream(new Stream.Duplex())      // true
isStream(new Stream.Transform())   // true
isStream(new Stream.PassThrough()) // true

But wait! There's more!

You can also test for isReadable(obj), isWritable(obj) and isDuplex(obj) to test for implementations of Streams2 (and Streams3) base classes.

var isReadable = require('isstream').isReadable
var isWritable = require('isstream').isWritable
var isDuplex = require('isstream').isDuplex
var Stream = require('stream')

isReadable(new Stream()) // false
isWritable(new Stream()) // false
isDuplex(new Stream())   // false

isReadable(new Stream.Readable())    // true
isReadable(new Stream.Writable())    // false
isReadable(new Stream.Duplex())      // true
isReadable(new Stream.Transform())   // true
isReadable(new Stream.PassThrough()) // true

isWritable(new Stream.Readable())    // false
isWritable(new Stream.Writable())    // true
isWritable(new Stream.Duplex())      // true
isWritable(new Stream.Transform())   // true
isWritable(new Stream.PassThrough()) // true

isDuplex(new Stream.Readable())    // false
isDuplex(new Stream.Writable())    // false
isDuplex(new Stream.Duplex())      // true
isDuplex(new Stream.Transform())   // true
isDuplex(new Stream.PassThrough()) // true

Reminder: when implementing your own streams, please use readable-stream rather than core streams.

License

isStream is Copyright (c) 2015 Rod Vagg @rvagg and licenced under the MIT licence. All rights not explicitly granted in the MIT license are reserved. See the included LICENSE.md file for more details.

Similar packages

Other packages similar to isstream

is-stream

The is-stream package provides similar functionality to isstream, allowing you to check if an object is a stream, readable stream, writable stream, or duplex stream. It is a lightweight and straightforward alternative.

stream

The stream package is part of Node.js core and provides a comprehensive API for working with streams. While it does not provide simple type-checking functions like isstream, it offers extensive functionality for creating and managing streams.

through2

The through2 package is a tiny wrapper around Node.js streams2 Transform to avoid explicit subclassing noise. It is more focused on stream transformation but can be used in conjunction with isstream for type-checking.