feat: let renovate pin version of postgres used in CI and local dev
Add a POSTGRES_DOCKER_IMAGE
variable which is used to specify the
postgres image to use in CI for running tests. This variable will be
respected both by CI jobs which spin up a GitLab CI service and pytest
spinning up its own container.
Teach renovate how to update this image.
For local development, specify the version of the postgres image to be used. This then becomes visible to renovate for update.
Renovate recognises that the same postgres dependency is used and so
will naturally group updating POSTGRES_DOCKER_IMAGE
and the use of
image: postgres:...
in the docker-compose.yml
file together.
The renovate configuration was tested locally in a testing branch of the ballots webapp.
We cannot yet get renovate to simultaneously update the postgres version used when the application is deployed and so add a comment which we hope, probably in vain, people will read in renovate-opened MRs :).
Closes #117 (closed)