ci: rework test_api job

Part-of: <https://dev.funkwhale.audio/funkwhale/funkwhale/-/merge_requests/2286>

.gitlab-ci.yml

@@ -172,15 +172,21 @@ lint_front:
 
 test_api:
   interruptible: true
+  retry: 1
+  stage: test
+  rules:
+    - if: $CI_COMMIT_BRANCH =~ /(stable|develop)/
+    - changes: [api/**/*]
+
+  image: $CI_REGISTRY/funkwhale/ci/python-funkwhale-api:$PYTHON_VERSION
+  parallel:
+    matrix:
+      - PYTHON_VERSION: ["3.8", "3.9", "3.10", "3.11"]
   services:
     - postgres:15-alpine
     - redis:7-alpine
-  stage: test
-  retry: 1
   cache:
-    key: "$CI_PROJECT_ID__pip_cache"
-    paths:
-      - "$PIP_CACHE_DIR"
+    paths: ["$PIP_CACHE_DIR"]
   variables:
     DATABASE_URL: "postgresql://postgres@postgres/postgres"
     FUNKWHALE_URL: "https://funkwhale.ci"
@@ -189,9 +195,16 @@ test_api:
     CACHE_URL: "redis://redis:6379/0"
   before_script:
     - cd api
-    - poetry install --no-root
+    - poetry install
   script:
-    - poetry run pytest --cov-report xml --cov-report term-missing:skip-covered --cov=funkwhale_api --junitxml=report.xml tests/
+    - >
+      poetry run pytest
+      --junitxml=report.xml
+      --cov
+      --cov-config=pyproject.toml
+      --cov-report=term-missing:skip-covered
+      --cov-report=xml
+      tests
   artifacts:
     expire_in: 2 weeks
     reports:
@@ -199,17 +212,7 @@ test_api:
       coverage_report:
         coverage_format: cobertura
         path: api/coverage.xml
-  parallel:
-    matrix:
-      - PY_VER: ["3.8", "3.9", "3.10", "3.11"]
-  image: $CI_REGISTRY/funkwhale/backend-test-docker:$PY_VER
   coverage: '/TOTAL\s*\d*\s*\d*\s*(\d*%)/'
-  rules:
-    - if: $CI_PIPELINE_SOURCE == "merge_request_event" || $CI_PIPELINE_SOURCE == "push"
-      changes:
-        - api/**/*
-    - if: $CI_COMMIT_REF_PROTECTED == "true"
-      when: always
 
 # Those tests are disabled for now since no vitest dom emulation is providing
 # AudioContext, which is required for our HTML audio player

api/pyproject.toml

@@ -175,7 +175,7 @@ env = [
 
 [tool.coverage.run]
 plugins = ["django_coverage_plugin"]
-include = ["funkwhale_api/*"]
+source = ["funkwhale_api"]
 omit = [
   "*migrations*",
   "*tests*",