Release v2.9.0

Added

• Added micro module implementing services ADR-32 (#566)

Thank you to @charbonnierg for the community implementation that served as a kick-off point.

import asyncio
import contextlib
import signal

import nats
import nats.micro


async def echo(req) -> None:
   """Echo the request data back to the client."""
   await req.respond(req.data)


async def main():
   # Define an event to signal when to quit
   quit_event = asyncio.Event()

   # Attach signal handler to the event loop
   loop = asyncio.get_event_loop()
   for sig in (signal.Signals.SIGINT, signal.Signals.SIGTERM):
       loop.add_signal_handler(sig, lambda *_: quit_event.set())

   # Create an async exit stack
   async with contextlib.AsyncExitStack() as stack:
       # Connect to NATS
       nc = await stack.enter_async_context(await nats.connect())

       # Add the service
       service = await stack.enter_async_context(
           await nats.micro.add_service(nc, name="demo_service", version="0.0.1")
       )

       group = service.add_group(name="demo")
       # Add an endpoint to the service
       await group.add_endpoint(
           name="echo",
           handler=echo,
       )
       # Wait for the quit event
       await quit_event.wait()


if __name__ == "__main__":
   asyncio.run(main())

• Added pagination to JetStream stream info (#594)

nc = await nats.connect()
js = nc.jetstream()
jsm = nc.jsm()

for i in range(300):
  await jsm.add_stream(name=f"stream_{i}")

streams_page_1 = await jsm.streams_info(offset=0)
streams_page_1 = await jsm.streams_info(offset=256)

Fixed

• Fixed resource leak in JetStream push subscription (#597)

Release v2.8.0

Added

• Added publish_async method to jetstream

  ack_future = await js.publish_async("foo", b'bar')
  await ack_future

• Added the ability to file contents as user_credentials (#546)

from nats.aio.client import RawCredentials
...
await nats.connect(user_credentials=RawCredentials("<creds file contents as string>"))

Fixed

• Fixed a race condition that could trigger error callbacks if a timeout and a response from a request where in-conflict (#573).

Release v2.7.2

• Added heartbeat option to pull subscribers fetch API

  await sub.fetch(1, timeout=1, heartbeat=0.1)

  It can be useful to help distinguish API timeouts from not receiving messages:

  try:
    await sub.fetch(100, timeout=1, heartbeat=0.2)
  except nats.js.errors.FetchTimeoutError:
    # timeout due to not receiving messages
  except asyncio.TimeoutError:
    # unexpected timeout

• Added subject_transform to add_consumer

  await js.add_stream(
    name="TRANSFORMS",
    subjects=["test", "foo"],
    subject_transform=nats.js.api.SubjectTransform(
      src=">", dest="transformed.>"
    ),
  )

• Added subject_transform to sources as well:

  transformed_source = nats.js.api.StreamSource(
      name="TRANSFORMS",
      # The source filters cannot overlap.
      subject_transforms=[
          nats.js.api.SubjectTransform(
              src="transformed.>", dest="fromtest.transformed.>"
          ),
          nats.js.api.SubjectTransform(
              src="foo.>", dest="fromtest.foo.>"
          ),
      ],
  )
  await js.add_stream(
    name="SOURCING",
    sources=[transformed_source],
  )

• Added backoff option to add_consumer

  await js.add_consumer(
            "events",
            durable_name="a",
            max_deliver=3,    # has to be greater than length as backoff array
            backoff=[1, 2],   # defined in seconds
            ack_wait=999999,  # ignored once using backoff
            max_ack_pending=3,
            filter_subject="events.>",
        )

• Added compression to add_consumer

  await js.add_stream(
    name="COMPRESSION",
    subjects=["test", "foo"],
    compression="s2",
  )

• Added metadata to add_stream

  await js.add_stream(
      name="META",
      subjects=["test", "foo"],
      metadata={'foo': 'bar'},
  )

Release v2.7.0

Added

• Added support for multiple filter consumers when using nats-server +v2.10
  This is only supported when using the pull_subscribe_bind API:

await jsm.add_stream(name="multi", subjects=["a", "b", "c.>"])
cinfo = await jsm.add_consumer(
    "multi",
    name="myconsumer",
    filter_subjects=["a", "b"],
)
psub = await js.pull_subscribe_bind("multi", "myconsumer")
msgs = await psub.fetch(2)
for msg in msgs:
  await msg.ack()

• Added subjects_filter option to js.stream_info() API

stream = await js.add_stream(name="foo", subjects=["foo.>"])
for i in range(0, 5):
    await js.publish("foo.%d" % i, b'A')

si = await js.stream_info("foo", subjects_filter=">")
print(si.state.subjects)
# => {'foo.0': 1, 'foo.1': 1, 'foo.2': 1, 'foo.3': 1, 'foo.4': 1}

Changed

• Changed kv.watch default inactive_threshold cleanup timeout to be 5 minutes.
  It can now be customized as well by passing inactive_threshold as argument in seconds:

w = await kv.watchall(inactive_threshold=30.0)

• Changed pull_subscribe_bind first argument to be called consumer instead of durable
  since it also supports ephemeral consumers. This should be backwards compatible.

psub = await js.pull_subscribe_bind(consumer="myconsumer", stream="test")

Release v2.6.0

Added

• Added support to ephemeral pull consumers (#412)

Changed

• Changed default max control line to 4K as in the server since v2.2

Fixed

• Fixed ordered consumer implementation not being recreated when consumer deleted (#510)
• Fixed accounting issue pending data which would have caused slow consumers on ordered consumers using next_msg
• Fixed subscribe to missing stream not raising NotFoundError (#499 )

Full Changelog: v2.5.0...v2.6.0

Release v2.5.0

Added

• Add tls_handshake_first option (#511)

Fixed

• fix: improve types on kv/object_store updates by @tekumara in #497
• fix: KeyWatcher.updates() returns type of Entry | None by @tekumara in #500

New Contributors

• @tekumara made their first contribution in #497

Full Changelog: v2.4.0...v2.5.0

Release v2.4.0

Fixed

• Fixed Python 3.7 compatibility: use uuid4 to gen unique task names by @Lancetnik in #457
• Fixed websocket connection when not using TLS (#463)
• Remove msg from fut.cancel to ensure backward compatibility by @raprek in #479
• Fixed connect() by @dsodx in #484
• Fixed auth to respect provided server address username and password if no_auth_user is set by @anthonyjacques20 in #488
• Fixed reconnect in websockets: CLOSED WS connection detection by @sebastian-king in #477

Added

• Consumers info offset by @raprek in #459
• Allow passing nkey seed as string by @databasedav in #468

Improved

• Coherently use f-strings by @floscha in #460
• Add main branch from nats-server to CI by @wallyqs in #464
• Fix docstring typo by @floscha in #473
• Add missing pull subscriber declaration to docstring by @floscha in #476
• Add code example to Subscription.messages docstring by @floscha in #481

New Contributors

• @floscha made their first contribution in #460
• @raprek made their first contribution in #459
• @anthonyjacques20 made their first contribution in #488
• @dsodx made their first contribution in #484
• @sebastian-king made their first contribution in #477

Full Changelog: v2.3.1...v2.4.0

Release v2.3.0

pip install nats-py

Added

• Added object store feature based on initial contribution by @domderen (#452 || #446)

Upload example:

import nats
import asyncio

async def main():
    nc = await nats.connect("locahost", name="object.py")
    js = nc.jetstream()
    obs = await js.create_object_store("nats-py-object-store")

    object_name = 'my-file.mp4'
    with open(object_name) as f:
        await obs.put(object_name, f)

    await nc.close()

if __name__ == '__main__':
    asyncio.run(main())

Download example:

import nats
import asyncio

async def main():
    nc = await nats.connect("localhost", name="object.py")
    js = nc.jetstream()
    obs = await js.object_store("nats-py-object-store")

    files = await obs.list()
    for f in files:
        print(f.name, "-", f.size)

    object_name = 'my-file.mp4'
    with open("copy-"+object_name, 'w') as f:
        await obs.get(object_name, f)

    await nc.close()

if __name__ == '__main__':
    asyncio.run(main())

• Updated the WebSocketTransport to detect the attempt to upgrade the connection to TLS by @allanbank (#443)

Fixed

• Fixed example from jetstream pull subscriber sample by @csuriano23 (#366)
• Fixed issue where protocol was changed for ws and wss if no port was
  provided by @bvanelli (#371)
• Fixed untreated error callbacks when using websockets by @bvanelli (#361 || #375)
• Fixes to next_msg and tasks cancellation (#446)

Changed

• Updated signatures for 'servers' and 'discovered_servers' properties by @jonchammer (#374)
• Move configs from setup.cfg into pyproject.toml by @orsinium (#394)
• Forbid None for Msg.Metadata fields by @orsinium (#401)
• Convert republish value into dataclass by @orsinium (#405)
• Change the type of client_id to int by @kkqy (#435)
• Raise asyncio.CancelledError back by @charbonnierg (#378)
• Send credentials even if no_auth_required is set on INFO (#399)
• Add sid property to nats.aio.msg.Msg class by @charbonnierg (#430)
• Add custom inbox prefix support for JS pull subscribe by @alparslanavci (#419)

Internal changes

• Sort imports by @orsinium (#385)
• Make all type annotations lazy by @orsinium (#386)
• Use the new type annotations syntax by @orsinium (#388)
• Fixed incorrect formatting in .travis.yml by @WillCodeCo (#420)

New Contributors

• @csuriano23 made their first contribution in #366
• @jonchammer made their first contribution in #374
• @WillCodeCo made their first contribution in #420
• @allanbank made their first contribution in #443
• @kkqy made their first contribution in #435
• @alparslanavci made their first contribution in #419

Release v2.2.0

Added

• Added support sending requests with reconnected client (by @charbonnierg #343)
• Added websockets support (by @bvanelli #356)
• Added support for new KV features (#347 | #355)
  • direct mode
  • republish
• Added support to create consumers with a name (#358)

Changed

• Modernizes the way we package and distribute nats.py by using PEP621 (by @4383 #341)
• Removed the server address from reconnection logs in examples (by @4383 #346)
• Makes connections examples more configurable (by @4383 (#342)
• update account limits (#357)

Fixed

• Fixed typos (by @4383 #338)
• Fixed Client.publish docstring typo (by @blablatdinov (#344)
• Fixed cleaning up subscriptions with message iterator (by @bvanelli (#350)
• Fixed support v2 JS.ACK format (by @bruth (#351)

Full Changelog: v2.1.7...v2.2.0

Release v2.1.7

Changed

• Changed nc.request to have more unique inboxes to avoid accidental reuse of response tokens #335