What's Changed

The current release is planned as a latest feature release before 0.6.0. All other 0.5.19+ releases will contain only minor bugfixes and all the team work will be focused on next major one.

There a lot of changes we want to present you now though!

New RPC feature

Our old broker.publish(..., rpc=True) implementation was very limited and ugly. Now we present you a much suitable way to do the same thing - broker.request(...)

from faststream import FastStream
from faststream.nats import NatsBroker, NatsResponse, NatsMessage

broker = NatsBroker()

@broker.subscriber("test")
async def echo_handler(msg):
    return NatsResponse(msg, headers={"x-token": "some-token"})

@app.after_startup
async def test():
    # The old implementation was returning just a message body,
    # so you wasn't be able to check response headers, etc
    msg_body: str = await broker.publish("ping", "test", rpc=True)
    assert msg_body == "ping"
    
    # Now request return the whole message and you can validate any part of it
    # moreover it triggers all your middlewares
    response: NatsMessage = await broker.request("ping", "test")

Exception Middleware

Community asked and community did! Sorry, we've been putting off this job for too long. Thanks for @Rusich90 to help us! Now you can wrap your application by a suitable exception handlers. Just check the new documentation to learn more.

Details

Also, there are a lot of minor changes you can find below. Big thanks to all our old and new contributors! You are amazing ones!

• Bug: resolve missing seek on kafka fakeconsumer by @JonathanSerafini in https://github.com/airtai/faststream/pull/1682
• replace pip with uv in CI by @newonlynew in https://github.com/airtai/faststream/pull/1688
• Added support for JSON serialization and deserialization by other libraries by @ulbwa in https://github.com/airtai/faststream/pull/1687
• Fix batch nack by @kumaranvpl in https://github.com/airtai/faststream/pull/1689
• Remove unused ignores by @kumaranvpl in https://github.com/airtai/faststream/pull/1690
• docs: add Kafka HowTo section by @Lancetnik in https://github.com/airtai/faststream/pull/1686
• Add missed out group_instance_id as subscriber and router parameter by @kumaranvpl in https://github.com/airtai/faststream/pull/1695
• Set warn_unused_ignores mypy config to true by @kumaranvpl in https://github.com/airtai/faststream/pull/1694
• Skip building docs in pre-commit CI job by @kumaranvpl in https://github.com/airtai/faststream/pull/1704
• Fix to run check-docs-changes workflow in forks by @kumaranvpl in https://github.com/airtai/faststream/pull/1710
• feature/exception_middleware add exception middleware by @Rusich90 in https://github.com/airtai/faststream/pull/1604
• Remove mentions of faststream-gen by @kumaranvpl in https://github.com/airtai/faststream/pull/1717
• Fix multiple docs issues by @kumaranvpl in https://github.com/airtai/faststream/pull/1718
• CI: group Dependabot updates into one PR by @dolfinus in https://github.com/airtai/faststream/pull/1719
• feat: CLI DX improvements by @Lancetnik in https://github.com/airtai/faststream/pull/1723
• fix: use async test subscribers functions by @Lancetnik in https://github.com/airtai/faststream/pull/1725
• feat: add broker.request method by @Lancetnik in https://github.com/airtai/faststream/pull/1649

New Contributors

• @JonathanSerafini made their first contribution in https://github.com/airtai/faststream/pull/1682
• @Rusich90 made their first contribution in https://github.com/airtai/faststream/pull/1604
• @dolfinus made their first contribution in https://github.com/airtai/faststream/pull/1719

Full Changelog: https://github.com/airtai/faststream/compare/0.5.18...0.5.19