🎨 catalog: lifespan managers for fastapi apps

[pcrespov]

What do these changes do?

FastAPI has deprecated the on_startup and on_shutdown events in favor of the lifespan events contexts. This PR introduces a postgres_lifespan: LifespanManager as a demonstration of how app_lifespan can coordinate multiple independent lifespan managers within a single FastAPI application.

The initial focus is on standardizing the lifespan for a PostgreSQL database. Using postgres_lifespan centralizes the setup and teardown logic for PostgreSQL, allowing it to be shared across all microservices. The catalog service already incorporates postgres_lifespan into its own application lifespan. This should be used as example to extend to other micro-services

The example below corresponds to the output of test_app_lifespan_composition It shows how nested lifespans can be composed so that state flows cleanly from parent to child. It also demonstrates the order of execution during startup/shutdown and how errors affect that flow.

-> postgres_sync_engine starting ...
       -> postgres_async_engine starting ...
               -> app database starting ...
                        -> rabbitmq starting ...
                                -> app rpc-server starting ...
                                <- app rpc-server done (<1ms)
                        <- rabbitmq done (<1ms)
                <- app database done (1ms)
        <- postgres_async_engine done (1ms)
<- postgres_sync_engine done (1ms)

Future work will extend this approach to additional FastAPI apps and later to aiohttp-based services, enabling consistent and modular resource management across the stack.

• ⚠️ Note: When FastAPI(..., lifespan=app_lifespan) is used, the on_startup and on_shutdown events are not triggered.
• Recommended order for setting up a FastAPI application:
  1. Define the lifespan by composing the necessary modules.
  2. Create the app instance: app = FastAPI(lifespan=events.lifecycle)
  3. Add middlewares: app.add_middleware(...)
  4. Register routes: app.include_router(...)
  5. Set up exception handlers: app.add_exception_handler(...)
• The app's lifecycle is managed by the web server via the ASGI protocol, which standardizes communication between async Python apps and servers.

Related issue/s

• Preparation for WIP: Is34/catalog refactoring #7480
• Part of Add Lifespan events #4678

How to test

cd packages/service-library
make "install-dev[fastapi]"
pytest -vv tests/test_*lifespan*.py

Dev-ops

None

[codecov]

Codecov Report

Attention: Patch coverage is 90.51095% with 13 lines in your changes missing coverage. Please review.

Project coverage is 87.47%. Comparing base (e162382) to head (0ccb681).
Report is 1 commits behind head on master.

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #7483      +/-   ##
==========================================
+ Coverage   87.41%   87.47%   +0.06%     
==========================================
  Files        1740     1734       -6     
  Lines       67273    67132     -141     
  Branches     1140     1142       +2     
==========================================
- Hits        58806    58724      -82     
+ Misses       8146     8087      -59     
  Partials      321      321              

Flag	Coverage Δ
integrationtests	65.16% <100.00%> (+0.02%)	⬆️
unittests	86.65% <90.51%> (+0.05%)	⬆️

Components	Coverage Δ
api	∅ <ø> (∅)
pkg_aws_library	93.91% <ø> (ø)
pkg_dask_task_models_library	97.09% <ø> (ø)
pkg_models_library	91.94% <ø> (ø)
pkg_notifications_library	85.26% <ø> (ø)
pkg_postgres_database	88.18% <ø> (ø)
pkg_service_integration	70.03% <ø> (ø)
pkg_service_library	72.78% <72.91%> (+0.54%)	⬆️
pkg_settings_library	90.78% <ø> (ø)
pkg_simcore_sdk	85.40% <ø> (ø)
agent	96.46% <ø> (ø)
api_server	90.02% <ø> (ø)
autoscaling	96.08% <ø> (ø)
catalog	91.92% <100.00%> (+0.09%)	⬆️
clusters_keeper	99.24% <ø> (ø)
dask_sidecar	91.29% <ø> (ø)
datcore_adapter	98.12% <ø> (ø)
director	76.78% <ø> (ø)
director_v2	91.30% <100.00%> (ø)
dynamic_scheduler	97.35% <ø> (ø)
dynamic_sidecar	90.11% <ø> (ø)
efs_guardian	89.79% <ø> (ø)
invitations	93.28% <ø> (ø)
payments	92.66% <ø> (ø)
resource_usage_tracker	89.12% <ø> (-0.11%)	⬇️
storage	87.72% <ø> (+0.07%)	⬆️
webclient	∅ <ø> (∅)
webserver	85.91% <ø> (-0.04%)	⬇️

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[sanderegg]

Thanks, this looks very promising!
A few questions here and there.

[GitHK]

Please consider my naming change issue. I'd like to keep things aligned accross. I have the pattern I mentioned in my comment already in place in two services and I would like to avoid having different styles.

[matusdrobuliak66]

👍

[GitHK]

As discussed OK with the changes. Just let's alright the naming. I'd like to avoid having it mixed, which is even more confusing

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud