mq-bridge-pulsar (Python)

An Apache Pulsar endpoint for mq-bridge-py, shipped as a native plugin. The package contains no Python implementation of Pulsar — it bundles the compiled Rust endpoint and registers it with mq-bridge, so Python, Node.js and Rust all run the same code and the same delivery semantics.

pip install mq-bridge-py mq-bridge-pulsar

import mq_bridge
import mq_bridge_pulsar

mq_bridge_pulsar.register()   # call once, before starting routes

route = mq_bridge.Route.from_str("""
pulsar_to_file:
  input:
    custom:
      name: pulsar
      config:
        url: "pulsar://localhost:6650"
        topic: "persistent://public/default/orders"
        subscription: "order-workers"
  output:
    file:
      path: "orders.jsonl"
""")
route.start()

register() returns the endpoint name (pulsar) and is a no-op when called again. It raises ImportError if mq-bridge is missing and FileNotFoundError if the wheel does not carry a library for this platform.

The two packages are independent: mq-bridge has no Pulsar dependency, and neither package forces an upgrade of the other. A plugin is native code with the same privileges as the interpreter — install it as you would any other native dependency.

The generic wheel builder is supplied by mq-bridge:

pip install "mq-bridge-py[plugin-packaging]"
python -m mq_bridge.plugin_packaging --package python/mq_bridge_pulsar --out dist

Testing

python/tests/ exercises the endpoint the way Python actually loads it — as a native plugin through the ABI — so it complements, rather than repeats, the directly linked Rust tests.

docker compose -f tests/docker-compose.yml up -d
pip install mq-bridge-py mq-bridge-pulsar pytest
pytest python/tests -v
docker compose -f tests/docker-compose.yml down

Every test skips rather than fails when the packages are missing or no broker is listening, so the file is safe to collect anywhere.

One trap is worth knowing: a wheel is a compiled artifact, so an installed mq-bridge-pulsar is easily older than this checkout, and a fix you just made here will not be in it. The tests probe for that and skip with instructions instead of reporting a confusing unknown field failure. To test what you just wrote, rebuild and reinstall first:

pip install "mq-bridge-py[plugin-packaging]"
python -m mq_bridge.plugin_packaging --package python/mq_bridge_pulsar --out python/dist
pip install --force-reinstall python/dist/*.whl

Building the wheel

The generic builder shipped by mq-bridge builds the Rust cdylib, stages it into the package, and tags the wheel for the host platform:

python -m mq_bridge.plugin_packaging --package python/mq_bridge_pulsar --out dist

Run it once per operating system and architecture you publish for; building pulsar-rs needs protoc on PATH.