Add docs build workflow

Checkout current atlas source

Install doxygen

Install latex

Install texlive-full

.github/docs-config.yml

@@ -0,0 +1,14 @@
+# note: each step is executed in own process
+build-steps:
+  - git clone --depth 1 https://github.com/ecmwf/atlas-docs.git $RUNNER_TEMP/atlas-docs
+  - sudo apt install -y -q doxygen texlive-full
+  - | 
+    cd $RUNNER_TEMP/atlas-docs
+    make PUBLIC=1 WITH_ECKIT=1 WITH_DOXYGEN=1 ATLAS_SOURCE_DIR=$GITHUB_WORKSPACE clean html
+    echo "DOC_BUILD_PATH=$RUNNER_TEMP/atlas-docs/build/html" >> "$GITHUB_ENV"
+
+hosts:
+  ecmwf-sites:
+    space: docs
+    name: atlas
+

.github/workflows/docs.yml

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+name: docs
+
+on:
+  push:
+    tags:
+      - '**'
+
+  workflow_dispatch: ~
+
+jobs:
+  publish:
+    uses: ecmwf-actions/reusable-workflows/.github/workflows/cd-docs.yml@v2
+    secrets: inherit
+    with:
+      config: .github/docs-config.yml