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Language bindings API

The core engine is a Rust library, but the same engine ships as native bindings for Python and Node.js. The Tokio runtime, broker I/O, routing, and batching all stay in Rust; the binding is a thin layer for handlers and configuration.

LanguagePackageInstall
Rustmq-bridgecargo add mq-bridge
Pythonmq-bridge-pypip install mq-bridge-py
Node.jsmq-bridgenpm install mq-bridge

The core of the library are the MessageConsumer and MessagePublisher traits, found in mq_bridge::traits.

Config loaders

Constructor names are kept aligned across languages, so a config loader reads the same in either binding (Python uses snake_case, Node uses camelCase):

PurposePythonNode.js
Load a route from a YAML/JSON fileRoute.from_fileRoute.fromFile
Load from an in-memory YAML/JSON stringRoute.from_strRoute.fromStr
Load from a parsed dict / JS objectRoute.from_configRoute.fromConfig
Build a publisher endpointthe matching Publisher.*the matching Publisher.*

The name argument is optional in both: pass it to select one entry from a routes:/publishers: document, or omit it to treat the config as a single bare route/endpoint body.

This is the natural companion to the configuration-first workflow: design and test a route in the UI, export the JSON/YAML, then load that exact config from your code. See the Embed the library tutorial for full examples in each language.

Extending from a binding

Custom endpoints and middleware are not Rust-only. Both bindings expose register_endpoint / register_middleware (registerEndpoint / registerMiddleware in Node), with the same batch, ack and request-reply semantics as a Rust CustomEndpointFactory, and both can load a compiled plugin — mq_bridge.load_endpoint_plugin(path) in Python, loadEndpointPlugin(path) in Node — so one Rust implementation serves every language. Registration is process-global, keyed by name, and must happen before a route that names it starts; a duplicate name is an error rather than a silent replacement.

Full examples in Custom endpoints and Native plugins.

Rust API surface

The Rust crate exposes the full engine. The main types:

  • Route::new(input, output) — a pipeline from one endpoint to one endpoint, with .with_batch_size(n), .with_handler(h), .add_handler(kind, f), .deploy(name) / .run().
  • Endpoint — protocol adapters (Endpoint::new_memory, Endpoint::null, …) plus the serde-configured variants.
  • Publisher::new(endpoint) — publish into a route’s input or any endpoint.
  • Handlers: CommandHandler (1-to-1/1-to-0), EventHandler (terminal 1-to-N), and TypeHandler (dispatches on the kind metadata field, deserializing payloads).
  • CanonicalMessage — the unified message type all handlers work with; msg!(&value, "kind") builds one with a kind.

See Core concepts and Learn the architecture for the handler model, and the Rust docs on docs.rs for the full API.

Notes

  • The Python binding holds up under load on the third-party http-arena.com requests-per-second HTTP benchmark (a live leaderboard — rankings shift over time).
  • A binding is a thin layer: routing, batching, and broker I/O stay in Rust regardless of which language calls in, so behaviour and reliability match the Rust engine.