repository·master·Indexed 23 days ago
https://github.com/crossbario/autobahn-jsAn open-source JavaScript implementation of the Web Application Messaging Protocol (WAMP) v2. It provides asynchronous Remote Procedure Calls (RPC) and Publish/Subscribe (PubSub) patterns over WebSockets for both Node.js and modern browsers. Features include support for JSON, Msgpack, and CBOR serializers, WAMP-CRA authentication, and a promise-based API using when.js.
Autobahn|JS is a WAMP v2 implementation providing:
when.js for promises, supporting progress for WAMP progressive calls.AutobahnJS is a WAMP (Web Application Messaging Protocol) library. The project is currently in a modernization phase, transitioning from legacy build tools to a modern stack.
Key Environment Requirements:
ws dependency).autobahn package is licensed under MIT, while autobahn-xbr is licensed under Apache-2.0.Autobahn|JS supports the following environments:
The project is moving toward providing type safety without a full migration to TypeScript. The planned approach (Track A) includes:
.d.ts type definition files for both autobahn and autobahn-xbr packages.checkJs mode for CI validation.Note: The codebase is not being rewritten in TypeScript to minimize risk to existing customer applications.
Autobahn|JS does not facilitate direct communication between application components. Instead, it enables components (such as a browser frontend and a Node.js backend) to connect to a WAMP router.
The router acts as a central hub that performs rule-based routing for application messages (events and RPC calls). No application code runs inside the router itself.
Recommended routers include Crossbar.io, which is highly compatible with the WAMP v2 protocol.
When performing WAMP operations, you receive objects that allow you to manage the lifecycle of that specific operation.
Registration Object (from session.register()):
registration.id: Registration ID.registration.procedure: Procedure URI.registration.unregister(): Unregisters the procedure.Subscription Object (from session.subscribe()):
subscription.id: Subscription ID.subscription.topic: Topic URI.subscription.unsubscribe(): Unsubscribes from the topic.Publication Object (from session.publish() when acknowledge: true):
publication.id: Publication ID.The project uses different bundling strategies depending on the package being built:
lib/autobahn.js.browserify with --standalone autobahn to create a standalone bundle.google-closure-compiler (mode: SIMPLE, target: ES2018) to produce build/autobahn.min.js.gzip -9 to produce build/autobahn.min.jgz.MD5, SHA1, and SHA256.lib/autobahn-xbr.js and JSON contracts from lib/contracts/*.json.esbuild (using --bundle and externalizing Node.js built-ins).esbuild to produce build/autobahn-xbr.min.js.gzip -9 to produce build/autobahn-xbr.min.jgz.The autobahn.Connection object provides two primary callbacks for lifecycle management:
onopenFired when the connection is established and a new WAMP session is created. It receives (session, details) where session is an autobahn.Session instance.
autobahn.Connection.onopen = function (session, details) {
// session is an instance of autobahn.Session
};oncloseFired when the connection is closed explicitly, lost, or failed to establish. It receives (reason, details).
Possible reason values:
"closed": Explicitly closed. No reconnection attempted."lost": Connection was established but lost. Automatic reconnection will happen unless you return a truthy value from this callback."unreachable": Connection could not be established (e.g., invalid URL). No reconnection attempted."unsupported": No WebSocket transport could be created.details contains the reason and message passed to .close(), but is not applicable for "lost" or "unreachable" cases.
autobahn.Connection.onopen = function (session, details) {
// Underlying transport to WAMP router established and new WAMP session started.
// session is an instance of autobahn.Session
};
autobahn.Connection.onclose = function (reason, details) {
// connection closed, lost or unable to connect
};A WAMP-based system is composed of loosely coupled application components (e.g., a browser frontend or a Node.js backend) that connect to a WAMP router.
The router is a generic component that does not run application code; its sole purpose is to provide routing for events and calls between components. This decoupling allows components to communicate without knowing each other's location or implementation details.
You can serve JSON data directly from a Crossbar.io node by configuring a web transport with a path of type json. The value key in the path configuration defines the JSON object that will be returned when that URL is requested.
{
"workers": [
{
"type": "router",
"transports": [
{
"type": "web",
"endpoint": {
"type": "tcp",
"port": 8080
},
"paths": {
"config": {
"type": "json",
"value": {
"nodes": [
"ws://localhost:8081/ws",
"ws://localhost:8082/ws",
"ws://localhost:8083/ws",
"ws://localhost:8084/ws"
]
}
}
}
}
]
}
]
}The build process is managed via scons.
Use scons to start the build process, which generates browser-compatible files including unminified JS, minified JS, and compressed versions.
Use scons -uc to clean up the build artifacts.