Verify documentation on CI

Author: mik-laj

.github/workflows/build-docs.yml

@@ -0,0 +1,31 @@
+name: Build documentation
+
+on:
+  push:
+  pull_request:
+    types: [opened, synchronize]
+
+jobs:
+  test:
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@v2
+    - name: Set up Python 3.9
+      uses: actions/setup-python@v2
+      with:
+        python-version: 3.9
+    - name: Install dependencies
+      run: |
+        python -m pip install --upgrade pip
+        pip install -r requirements.txt
+        pip install -r requirements_dev.txt
+        pip install -e .
+    - name: Build documentation
+      run: |
+        python -m sphinx -T -b html -d _build/doctrees -D language=en . _build/html --color -n -W
+    - uses: actions/upload-artifact@v2
+      name: 🚀 Upload docs as artifact
+      with:
+        name: airflow-website
+        path: './docs/_build/html'
+        if-no-files-found: error

docs/conf.py

@@ -58,4 +58,4 @@
 # Add any paths that contain custom static files (such as style sheets) here,
 # relative to this directory. They are copied after the builtin static files,
 # so a file named "default.css" will overwrite the builtin "default.css".
-html_static_path = ['_static']
+html_static_path = []

requirements_dev.txt

@@ -9,3 +9,5 @@ requests==2.22.0
 responses==0.10.12
 webob
 strict-rfc3339==0.7
+sphinx==4.0.2
+sphinx-rtd-theme==0.5.2