This was added in Celery 4 [1]. and appears to be incompatible with our approach of injecting "request_id" into task arguments (example exception below). Although our other apps are on Celery 5 our logs don't show any similar issues, probably because all their tasks are invoked without request IDs. In the longterm we should decide if we want to enable argument checking and fix the tracing approach, or stop tracing request IDs in Celery tasks. [1]: https://docs.celeryproject.org/en/stable/userguide/tasks.html#argument-checking 2021-11-01T11:37:36 delivery delivery ERROR None "RETRY: Email notification f69a9305-686f-42eb-a2ee-61bc2ba1f5f3 failed" [in /Users/benthorner/Documents/Projects/api/app/celery/provider_tasks.py:68] Traceback (most recent call last): File "/Users/benthorner/Documents/Projects/api/app/celery/provider_tasks.py", line 53, in deliver_email raise TypeError("test retry") TypeError: test retry [2021-11-01 11:37:36,385: ERROR/ForkPoolWorker-1] RETRY: Email notification f69a9305-686f-42eb-a2ee-61bc2ba1f5f3 failed Traceback (most recent call last): File "/Users/benthorner/Documents/Projects/api/app/celery/provider_tasks.py", line 53, in deliver_email raise TypeError("test retry") TypeError: test retry [2021-11-01 11:37:36,394: WARNING/ForkPoolWorker-1] Task deliver_email[449cd221-173c-4e18-83ac-229e88c029a5] reject requeue=False: deliver_email() got an unexpected keyword argument 'request_id' Traceback (most recent call last): File "/Users/benthorner/Documents/Projects/api/app/celery/provider_tasks.py", line 53, in deliver_email raise TypeError("test retry") TypeError: test retry During handling of the above exception, another exception occurred: Traceback (most recent call last): File "/Users/benthorner/.pyenv/versions/notifications-api/lib/python3.6/site-packages/celery/app/task.py", line 731, in retry S.apply_async() File "/Users/benthorner/.pyenv/versions/notifications-api/lib/python3.6/site-packages/celery/canvas.py", line 219, in apply_async return _apply(args, kwargs, **options) File "/Users/benthorner/.pyenv/versions/notifications-api/lib/python3.6/site-packages/celery/app/task.py", line 537, in apply_async check_arguments(*(args or ()), **(kwargs or {})) TypeError: deliver_email() got an unexpected keyword argument 'request_id' During handling of the above exception, another exception occurred: Traceback (most recent call last): File "/Users/benthorner/.pyenv/versions/notifications-api/lib/python3.6/site-packages/celery/app/trace.py", line 450, in trace_task R = retval = fun(*args, **kwargs) File "/Users/benthorner/Documents/Projects/api/app/celery/celery.py", line 74, in __call__ return super().__call__(*args, **kwargs) File "/Users/benthorner/.pyenv/versions/notifications-api/lib/python3.6/site-packages/celery/app/trace.py", line 731, in __protected_call__ return self.run(*args, **kwargs) File "/Users/benthorner/Documents/Projects/api/app/celery/provider_tasks.py", line 71, in deliver_email self.retry(queue=QueueNames.RETRY) File "/Users/benthorner/.pyenv/versions/notifications-api/lib/python3.6/site-packages/celery/app/task.py", line 733, in retry raise Reject(exc, requeue=False) celery.exceptions.Reject: (TypeError("deliver_email() got an unexpected keyword argument 'request_id'",), False)
GOV.UK Notify API
Contains:
- the public-facing REST API for GOV.UK Notify, which teams can integrate with using our clients
- an internal-only REST API built using Flask to manage services, users, templates, etc (this is what the admin app talks to)
- asynchronous workers built using Celery to put things on queues and read them off to be processed, sent to providers, updated, etc
Setting Up
Python version
At the moment we run Python 3.6 in production. You will run into problems if you try to use Python 3.5 or older, or Python 3.7 or newer.
AWS credentials
To run the API you will need appropriate AWS credentials. See the Wiki for more details.
environment.sh
Creating and edit an environment.sh file.
echo "
export NOTIFY_ENVIRONMENT='development'
export MMG_API_KEY='MMG_API_KEY'
export FIRETEXT_API_KEY='FIRETEXT_ACTUAL_KEY'
export NOTIFICATION_QUEUE_PREFIX='YOUR_OWN_PREFIX'
export FLASK_APP=application.py
export FLASK_ENV=development
export WERKZEUG_DEBUG_PIN=off
"> environment.sh
Things to change:
- Replace
YOUR_OWN_PREFIXwithlocal_dev_<first name>. - Run the following in the credentials repo to get the API keys.
notify-pass credentials/providers/api_keys
Postgres
Install Postgres.app.
Currently the API works with PostgreSQL 11. After installation, open the Postgres app, open the sidebar, and update or replace the default server with a compatible version.
Note: you may need to add the following directory to your PATH in order to bootstrap the app.
export PATH=${PATH}:/Applications/Postgres.app/Contents/Versions/11/bin/
Redis
To switch redis on you'll need to install it locally. On a OSX we've used brew for this. To use redis caching you need to switch it on by changing the config for development:
REDIS_ENABLED = True
To run the application
# install dependencies, etc.
make bootstrap
# run the web app
make run-flask
# run the background tasks
make run-celery
# run scheduled tasks (optional)
make run-celery-beat
To test the application
# install dependencies, etc.
make bootstrap
make test
To update application dependencies
requirements.txt file is generated from the requirements-app.txt in order to pin
versions of all nested dependencies. If requirements-app.txt has been changed (or
we want to update the unpinned nested dependencies) requirements.txt should be
regenerated with
make freeze-requirements
requirements.txt should be committed alongside requirements-app.txt changes.
To run one off tasks
Tasks are run through the flask command - run flask --help for more information. There are two sections we need to
care about: flask db contains alembic migration commands, and flask command contains all of our custom commands. For
example, to purge all dynamically generated functional test data, do the following:
Locally
flask command purge_functional_test_data -u <functional tests user name prefix>
On the server
cf run-task notify-api "flask command purge_functional_test_data -u <functional tests user name prefix>"
All commands and command options have a --help command if you need more information.