nameko-chassis 2.0.0a4

nameko-chassis provides an opinionated base class for building resilient, observable microservices.

docs
tests
package

nameko-chassis provides an opinionated base class for building resilient, observable microservices with the nameko framework.

Upcoming releases and distributed tracing

We’re aiming to add support for nameko 3.0 as soon as possible. However this will be a breaking change as we decided to drop Zipkin integration. Here’s the plan:

• 0.9.0 (current release) supports only nameko 2 and has Zipkin integration

• 1.0 (upcoming) supports both nameko 2 and 3 RC, while dropping Zipkin. If you need Zipkin support and your service is still on nameko 2, either stay on nameko-chassis 0.9, or upgrade to 1.x and manage nameko-zipkin yourself.

• In 2.0 we will only support nameko v3 and we intend to add OpenTelemetry integration to base Service class. You can still use OpenTelemetry with nameko-chassis 1.0 (provided you’re using nameko 3), but before 2.0 you’ll need to set it up yourself.

Features

By using nameko_chassis.service.Service, you’ll get:

• error reporting using Sentry

• integrated metrics endpoint for Prometheus

• helpers for service discovery

• partial* support for OpenTelemetry tracing

*You’ll need to call the instrumentors yourself, but we provide basic configuration as a dependency provider.

Installation

pip install nameko-chassis

You can also install the in-development version with:

pip install https://github.com/Emplocity/nameko-chassis/archive/master.zip

Usage

Base service class

from nameko.rpc import rpc
from nameko_chassis.service import Service


class MyService(Service):
    name = "my_service"

    @rpc
    def my_method(self):
        try:
            do_something()
        except Exception:
            self.sentry.captureException()

Note

If the RPC method raises an unhandled exception, nameko-sentry will automatically capture it to Sentry. The example above demonstrates the case when one wants to access the client manually.

Backdoor debugging

nameko-chassis.debug includes helpers for introspecting running services with nameko backdoor feature. For example if your service exposes backdoor on port 12345:

$ rlwrap nc -v localhost 12345
Connection to localhost 12345 port [tcp/*] succeeded!
Python 3.8.8 (default, Mar 23 2021, 11:02:14)
[GCC 9.3.0] on linux
Type "help", "copyright", "credits" or "license" for more information.
(InteractiveConsole)
>>> from nameko_chassis.debug import debug_runner
>>> debug_runner(runner)
╭──────────────────────────── sleeping_http_service ───────────────────────────╮
│ 19 entrypoints                                                               │
│ 15 dependencies                                                              │
│ running 1/10 worker threads                                                  │
│ ╭────────────────── Thread #0: SleepingHttpService.sleep ──────────────────╮ │
│ │                                                                          │ │
│ │ Args: ["<Request 'http://127.0.0.1:8000/sleep/500' [GET]>"]              │ │
│ │ Kwargs: {'duration': '500'}                                              │ │
│ │ Context data: {'X-B3-ParentSpanId': '1058ef878ab0fe32'}                  │ │
│ │                                                                          │ │
│ │ Traceback:                                                               │ │
│ │   File                                                                   │ │
│ │ "/home/zbigniewsiciarz/v/sleephttp/lib/python3.8/site-packages/eventlet… │ │
│ │ line 221, in main                                                        │ │
│ │     result = function(*args, **kwargs)                                   │ │
│ │   File                                                                   │ │
│ │ "/home/zbigniewsiciarz/v/sleephttp/lib/python3.8/site-packages/nameko/c… │ │
│ │ line 392, in _run_worker                                                 │ │
│ │     result = method(*worker_ctx.args, **worker_ctx.kwargs)               │ │
│ │   File "./app/service.py", line 73, in sleep                             │ │
│ │     time.sleep(duration)                                                 │ │
│ │   File                                                                   │ │
│ │ "/home/zbigniewsiciarz/v/sleephttp/lib/python3.8/site-packages/eventlet… │ │
│ │ line 36, in sleep                                                        │ │
│ │     hub.switch()                                                         │ │
│ │   File                                                                   │ │
│ │ "/home/zbigniewsiciarz/v/sleephttp/lib/python3.8/site-packages/eventlet… │ │
│ │ line 313, in switch                                                      │ │
│ │     return self.greenlet.switch()                                        │ │
│ │                                                                          │ │
│ ╰──────────────────────────────────────────────────────────────────────────╯ │
╰──────────────────────────────────────────────────────────────────────────────╯

Note

Pretty printing like in the above example requires rich.

Documentation

https://nameko-chassis.readthedocs.io/

Development

To run the all tests run:

tox

Authors

nameko-chassis is developed and maintained by Emplocity.

License

This work is released under the Apache 2.0 license.