Faster github actions

.github/workflows/ci.yml

@@ -22,8 +22,20 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        python-version: ["3.7", "3.8", "3.9", "3.10"]
-
+        python-version: ["3.8", "3.9", "3.10"]
+        django-version: ["django32", "django40", "djangomaster"]
+        database-version: ["mysql", "postgres", "sqlite"]
+        # This is needed because Python 3.7 is only supported by Django 3.2
+        include:
+          - python-version: "3.7"
+            django-version: "django32"
+            database-version: "mysql"
+          - python-version: "3.7"
+            django-version: "django32"
+            database-version: "postgres"
+          - python-version: "3.7"
+            django-version: "django32"
+            database-version: "sqlite"
     services:
       mysql:
         image: mysql
@@ -50,14 +62,28 @@ jobs:
 
     steps:
     - uses: actions/checkout@v2
+
     - name: Set up Python ${{ matrix.python-version }}
       uses: actions/setup-python@v2
       with:
         python-version: ${{ matrix.python-version }}
+
     - name: Install dependencies
       run: |
         python -m pip install --upgrade pip poetry setuptools wheel
         poetry install -v
+
+    - name: Compute tox environment name
+      id: tox-environment-name
+      shell: python
+      run: |
+        import sys
+        python_version = "py{}{}".format(*sys.version_info[:2])
+        django_version = {{ '"${{ matrix.django-version }}"' }}
+        database_version = {{ '"${{ matrix.database-version }}"' }}
+        result = "{}-{}-{}".format(python_version, django_version, database_version)
+        print("::set-output name=result::{}".format(result))
+
     - name: Run tox targets for ${{ matrix.python-version }}
       run: |
-        poetry run tox
+        poetry run tox -e ${{ steps.tox-environment-name.outputs.result }}