stratocaster

a totally tubular chromecast client

What?

stratocaster is a lightweight, Promise-based Chromecast "receiver" library, providing abstractions at various levels to facilitate most use cases. It does not include any tools for interacting with specific Chromecast applications (see babbling) but instead is meant to provide clean interfaces for implementing such interactions.

Here's how to use it:

import { ChromecastDevice, MEDIA_NS } from "stratocaster";

// in most practical cases, you will want to speak to a specific device:
const d = new ChromecastDevice("Family Room TV");

// ... but you can also search for one if you like:
const d = await ChromecastDevice.find(info => {
    return info.model === "Chromecast Ultra";
});

// ... or step through every device you can find:
for await (const device of ChromecastDevice.discover()) {
    // ...
}

// once you've found a device, typically you'll want to work with
// a specific app on the device; this opens the "generic media receiver":
const app = await d.app("CC1AD845");

// the app is not necessarily opened on the device at this point;
// if that's all you want to do, or if you want to show the app early
// while performing other preparations before interacting with it,
// you can explicitly launch the app:
await app.launch();

// communications are silo'd into different "channels," identified with
// a string namespace. the media namespace is commonly used to play videos
const channel = await app.channel(MEDIA_NS);

// JSON-encoded messages can be conveniently sent to channels, and the
// response message will be returned
const response = await ch.send({
    type: "LOAD",
    media: {
      contentId: "http://commondatastorage.googleapis.com/gtv-videos-bucket/sample/BigBuckBunny.mp4",
      streamType: "BUFFERED",
    },
});

// don't forget to close the device when done! this will disconnect any
// active connection and invalidate all app and channel references
d.close();

Why?

I've been using nodecastor for quite some time but finally got tired of waiting for mdns to compile. I could perhaps have switched to node-castv2, but that also has a mix of emitter and callback-style APIs that I would have to adapt, and I would also have to maintain my own typescript typings for it.

stratocaster is implemented natively in Typescript, with only pure JS dependencies (and as few of them as possible).

Also, I thought it'd be a fun project :)

Credits

• nodecastor for their initial research
• node-castv2 for their thorough protocol documentation