ci: improve coverage measurement

use a combiner job to resolve paths and aggregate coverage properly

.gitlab-ci.yml

@@ -27,6 +27,8 @@ include:
   - local: '/.gitlab/ci/python.yml'
   # Docker builds
   - local: '/.gitlab/ci/docker.yml'
+  # Code coverage
+  - local: '/.gitlab/ci/coverage.yml'
   # Code quality
   - local: '/.gitlab/ci/analysis.yml'
   # Documentation

.gitlab/ci/coverage.yml

+# ---------------------------
+# Code coverage
+# ---------------------------
+
+include:
+  # https://computing.docs.ligo.org/gitlab-ci-templates/
+  - project: computing/gitlab-ci-templates
+    # https://computing.docs.ligo.org/gitlab-ci-templates/python/
+    file: python.yml
+
+# -- coverage ---------------
+#
+# This job combinces the individual
+# coverage reports from each job
+# to make a proper coverage result
+#
+
+coverage:
+  stage: .post
+  extends:
+    # https://computing.docs.ligo.org/gitlab-ci-templates/python/#.python:coverage-combine
+    - .python:coverage-combine

.gitlab/ci/test.yml

@@ -24,3 +24,11 @@
     - tar -xf gwdatafind-server-*.tar.* --wildcards "*/tests" --strip-components=1
     # run pytest
     - !reference [".python:pytest", script]
+  # upload coverage file as an artifact to be combined later
+  artifacts:
+    when: always
+    paths:
+      - .coverage-*
+  # disable coverage total for test jobs, this is reported
+  # by the coverage job
+  coverage: null

pyproject.toml

@@ -5,9 +5,28 @@ requires = [
 ]
 build-backend = "setuptools.build_meta"
 
+# -- coverage.py
+
+[tool.coverage.paths]
+# map standard install paths back to the source to
+# enable merging coverage of installed module from
+# multiple platforms
+source = [
+    "gwdatafind_server/",  # <-- source path, must come first
+    "/usr/lib/python*/*-packages/gwdatafind_server/",
+    "/usr/local/lib/python*/*-packages/gwdatafind_server/",
+]
+
 [tool.coverage.run]
+# measure coverage for the gwdatafind_server package
 source = ["gwdatafind_server"]
 
+[tool.coverage.report]
+# print report with one decimal point
+precision = 1
+
+# -- pytest
+
 [tool.pytest.ini_options]
 addopts = "-r a"
 filterwarnings = [