Move documentation to a separate Github action from compile/tests

.github/workflows/ci.yml

@@ -8,8 +8,6 @@ jobs:
   build:
     name: ${{ matrix.config.name }}
     runs-on: ${{ matrix.config.os }}
-    env:
-      HDOC_PROJECT_API_KEY: ${{ secrets.HDOC_PROJECT_API_KEY }}
     strategy:
       fail-fast: false
       matrix:
@@ -166,13 +164,6 @@ jobs:
             message(FATAL_ERROR "Running tests failed!")
           endif()
 
-      - name: Documentation
-        if: ${{ startsWith(matrix.config.cxx, 'g++') && env.HDOC_PROJECT_API_KEY != '' }}
-        uses: hdoc/hdoc-github-action@v2
-        with:
-          compile-commands-path: out/compile_commands.json
-          hdoc-api-key: ${{ env.HDOC_PROJECT_API_KEY }}
-
       - name: Install Strip
         run: cmake --install out --prefix instdir --strip
 

.github/workflows/docs.yml

@@ -0,0 +1,25 @@
+name: docs
+
+on:
+  push:
+    branches: [main]
+
+jobs:
+  docs:
+    name: Generate documentation
+    if: github.repository == 'chromium/subspace'
+    runs-on: ubuntu-latest
+
+    steps:
+      - uses: actions/checkout@v1
+
+      - name: Configure
+        run: |
+          sudo apt install build-essential cmake ninja-build
+          cmake -G Ninja -B out -D CMAKE_EXPORT_COMPILE_COMMANDS=1
+      
+      - name: Documentation
+        uses: hdoc/hdoc-github-action@v2
+        with:
+          compile-commands-path: out/compile_commands.json
+          hdoc-api-key: ${{ secrets.HDOC_PROJECT_API_KEY }}