Faststream

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(...)`

python
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](https://faststream.airt.ai/latest/getting-started/middlewares/exception/) 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

What's Changed

* Added additional parameters to HandlerException by ulbwa in https://github.com/airtai/faststream/pull/1659
* Removed Doc and Added docstrings instead by Kirill-Stepankov in https://github.com/airtai/faststream/pull/1662
* feat (1663): support default values for Header by Lancetnik in https://github.com/airtai/faststream/pull/1667
* fix (1660): correct patch nested JStream subjects by Lancetnik in https://github.com/airtai/faststream/pull/1666
* fix: add ConfluentRouter FastAPI missed init options by Lancetnik in https://github.com/airtai/faststream/pull/1664
* Add kerberos support for confluent broker by kumaranvpl in https://github.com/airtai/faststream/pull/1670
* Fix nack for kafka and confluent brokers by kumaranvpl in https://github.com/airtai/faststream/pull/1678
* fix: support all RMQ exchanges in AsyncAPI by Lancetnik in https://github.com/airtai/faststream/pull/1679
* fix: catch parser errors by Lancetnik in https://github.com/airtai/faststream/pull/1680

New Contributors
* ulbwa made their first contribution in https://github.com/airtai/faststream/pull/1659
* Kirill-Stepankov made their first contribution in https://github.com/airtai/faststream/pull/1662

**Full Changelog**: https://github.com/airtai/faststream/compare/0.5.17...0.5.18

What's Changed

Just a hotfix for the following case:

python
broker.subscriber(...)
async def handler():
return NatsResponse(...)

await broker.publish(..., rpc=True)


* chore(deps): bump semgrep from 1.83.0 to 1.84.0 by dependabot in https://github.com/airtai/faststream/pull/1650
* chore(deps): bump mkdocs-material from 9.5.30 to 9.5.31 by dependabot in https://github.com/airtai/faststream/pull/1651
* Update Release Notes for 0.5.16 by faststream-release-notes-updater in https://github.com/airtai/faststream/pull/1652
* hotfix: correct NatsResponse processing in RPC case by Lancetnik in https://github.com/airtai/faststream/pull/1654


**Full Changelog**: https://github.com/airtai/faststream/compare/0.5.16...0.5.17

What's Changed

Well, seems like it is the biggest patch release ever 😃

Detail Responses

First of all, thanks to all new contributors, who helps us to improve the project! They made a huge impact to this release by adding new Kafka security mechanisms and extend Response API - now you can use `broker.Response` to publish detail information from handler

python
broker.subscriber("in")
broker.publisher("out")
async def handler(msg):
return Response(msg, headers={"response_header": "Hi!"}) or KafkaResponse, etc


ASGI

Also, we added a new huge feature - [**ASGI** support](https://faststream.airt.ai/latest/getting-started/asgi/#other-asgi-compatibility)!

Nope, we are not HTTP-framework now, but it is a little ASGI implementation to provide you with an ability to host documentation, use k8s http-probes and serve metrics in the same with you broker runtime without any dependencies.

You just need to use **AsgiFastStream** class

python
from faststream.nats import NatsBroker
from faststream.asgi import AsgiFastStream, make_ping_asgi

from prometheus_client import make_asgi_app
from prometheus_client.registry import CollectorRegistry

broker = NatsBroker()

prometheus_registry = CollectorRegistry()

app = AsgiFastStream(
broker,
asyncapi_path="/docs",
asgi_routes=[
("/health", make_ping_asgi(broker, timeout=5.0)),
("/metrics", make_asgi_app(registry=prometheus_registry))
]
)


And then you can run it like a regular ASGI app

shell
uvicorn main:app


Confluent partitions

One more thing - manual topic partition assignment for Confluent. We have it already for aiokafka, but missed it here... Now it was fixed!

python
from faststream.confluent import TopicPartition

broker.subscriber(partitions=[
TopicPartition("test-topic", partition=0),
])
async def handler():
...


Detail changes

* feat: add RMQ `fail_fast` option in 1647
* fix: correct nested `NatsRouter` subjects prefixes behavior
* fix typos by newonlynew in https://github.com/airtai/faststream/pull/1609
* Feat: extend response api by Flosckow in https://github.com/airtai/faststream/pull/1607
* Feature: GSSAPI (Kerberos) support by roma-frolov in https://github.com/airtai/faststream/pull/1633
* feat: add oauth support by filip-danieluk in https://github.com/airtai/faststream/pull/1632
* fix: patch broker within testbroker context only by sfran96 in https://github.com/airtai/faststream/pull/1619
* feat: ASGI support by Lancetnik in https://github.com/airtai/faststream/pull/1635

New Contributors
* newonlynew made their first contribution in https://github.com/airtai/faststream/pull/1609
* roma-frolov made their first contribution in https://github.com/airtai/faststream/pull/1633
* filip-danieluk made their first contribution in https://github.com/airtai/faststream/pull/1632
* sfran96 made their first contribution in https://github.com/airtai/faststream/pull/1619

**Full Changelog**: https://github.com/airtai/faststream/compare/0.5.15...0.5.16

What's Changed

Finally, **FastStream** has a Kafka pattern subscription! This is another step forward in our [**Roadmap**](https://github.com/airtai/faststream/issues/1510) moving us to **0.6.0** and futher!

python
from faststream import Path
from faststream.kafka import KafkaBroker

broker = KafkaBroker()

broker.subscriber(pattern="logs.{level}")
async def base_handler(
body: str,
level: str = Path(),
):
...


Also, all brokers now supports a new `ping` method to check real broker connection

python
is_connected: bool = await broker.ping()


This is a little, but important change for [K8S probes](https://github.com/airtai/faststream/issues/1181) support

More other there are a lot of bugfixes and improvements from our contributors! Thanks to all of these amazing people!

* feat(multiprocess): restart child processes if they are not alive by gostilovichd in https://github.com/airtai/faststream/pull/1550
* fix: use typing_extensions.TypedDict import by Lancetnik in https://github.com/airtai/faststream/pull/1575
* fix: correct single dataclass argument AsyncAPI payload generation by Lancetnik in https://github.com/airtai/faststream/pull/1591
* fix (1598): use config with NATS PullSub by Lancetnik in https://github.com/airtai/faststream/pull/1599
* feat: default call_name for broker.subscriber by KrySeyt in https://github.com/airtai/faststream/pull/1589
* Feat: init ping method by Flosckow in https://github.com/airtai/faststream/pull/1592
* chore: bump nats-py requirement by Lancetnik in https://github.com/airtai/faststream/pull/1600
* fix: add pattern checking by spataphore1337 in https://github.com/airtai/faststream/pull/1590

New Contributors

* gostilovichd made their first contribution in https://github.com/airtai/faststream/pull/1550
* KrySeyt made their first contribution in https://github.com/airtai/faststream/pull/1589
* Flosckow made their first contribution in https://github.com/airtai/faststream/pull/1592

**Full Changelog**: https://github.com/airtai/faststream/compare/0.5.14...0.5.15

What's Changed
* Update Release Notes for 0.5.13 by faststream-release-notes-updater in https://github.com/airtai/faststream/pull/1548
* Add allow_auto_create_topics to make automatic topic creation configurable by kumaranvpl in https://github.com/airtai/faststream/pull/1556


**Full Changelog**: https://github.com/airtai/faststream/compare/0.5.13...0.5.14