f: parametrize postgres installations

.github/workflows/tests.yml

@@ -13,16 +13,22 @@ jobs:
       fail-fast: false
       matrix:
         python-version: [3.7, 3.8, 3.9, pypy3]
+        postgres-version: [9.5, 9.6, 10, 11, 12, 12]
     env:
       OS: ubuntu-latest
       PYTHON: ${{ matrix.python-version }}
+      POSTGRES: ${{ matrix.postgres-version }}
 
     steps:
     - uses: actions/checkout@v2
     - name: Set up Python ${{ matrix.python-version }}
       uses: actions/setup-python@v2
       with:
         python-version: ${{ matrix.python-version }}
+    - name: Install postgresql
+      run: |
+        ./scripts/setup-postgresql.sh
+        sudo apt install -y postgresql-${{ matrix.postgres-version }}
     - name: Install dependencies
       run: |
         python -m pip install --upgrade pip

scripts/install-postgresql.sh

@@ -0,0 +1,9 @@
+#!/bin/bash
+# Create the file repository configuration:
+sudo sh -c 'echo "deb http://apt.postgresql.org/pub/repos/apt $(lsb_release -cs)-pgdg main" > /etc/apt/sources.list.d/pgdg.list'
+
+# Import the repository signing key:
+wget --quiet -O - https://www.postgresql.org/media/keys/ACCC4CF8.asc | sudo apt-key add -
+
+# Update the package lists:
+sudo apt-get update