Add the build_docs composite action to simplify the main workflow

Author: seisman

.github/workflows/actions/build_docs/action.yml

@@ -0,0 +1,75 @@
+name: Build Docs
+description: Build the documentation
+inputs:
+  os:
+    description: 'Operating system'
+    required: true
+    default: 'ubuntu-latest'
+
+runs:
+  using: 'composite'
+  steps:
+    - name: Get current week number of year
+      id: date
+      run: echo "date=$(date +%Y-W%W)" >> $GITHUB_OUTPUT  # e.g., 2024-W19
+
+    # Install Micromamba with conda-forge dependencies
+    - name: Setup Micromamba
+      uses: mamba-org/setup-micromamba@v2.0.4
+      with:
+        environment-name: pygmt
+        cache-environment: true
+        # environment cache is persistent for one week.
+        cache-environment-key: micromamba-environment-${{ steps.date.outputs.date }}
+        create-args: >-
+          python=3.13
+          gmt=6.5.0
+          ghostscript=10.04.0
+          numpy
+          pandas
+          xarray
+          netCDF4
+          packaging
+          contextily
+          geopandas
+          ipython
+          pyarrow-core
+          rioxarray
+          make
+          pip
+          python-build
+          geodatasets
+          myst-nb
+          panel
+          sphinx>=6.2
+          sphinx-autodoc-typehints
+          sphinx-copybutton
+          sphinx-design
+          sphinx-gallery
+          sphinx_rtd_theme
+          cairosvg
+          sphinxcontrib-svg2pdfconverter
+          tectonic
+
+    # Download cached remote files (artifacts) from GitHub
+    - name: Download remote data from GitHub
+      run: |
+        # Download cached files to ~/.gmt directory and list them
+        gh run download --name gmt-cache --dir ~/.gmt/
+        # Change modification times of the two files, so GMT won't refresh it
+        touch ~/.gmt/gmt_data_server.txt ~/.gmt/gmt_hash_server.txt
+        ls -lhR ~/.gmt
+      env:
+        GH_TOKEN: ${{ github.token }}
+
+    # Install the package that we want to test
+    - name: Install the package
+      run: |
+        python -m build --sdist
+        python -m pip install dist/*
+
+    - name: Build the HTML documentation
+      run: make -C doc clean html
+
+    - name: Build the PDF documentation
+      run:  make -C doc pdf

.github/workflows/ci_docs.yml

@@ -76,70 +76,9 @@ jobs:
           fetch-depth: 0
           persist-credentials: false
 
-      - name: Get current week number of year
-        id: date
-        run: echo "date=$(date +%Y-W%W)" >> $GITHUB_OUTPUT  # e.g., 2024-W19
-
-      # Install Micromamba with conda-forge dependencies
-      - name: Setup Micromamba
-        uses: mamba-org/setup-micromamba@v2.0.4
+      - uses: ./.github/workflows/actions/build_docs/action.yml
         with:
-          environment-name: pygmt
-          cache-environment: true
-          # environment cache is persistent for one week.
-          cache-environment-key: micromamba-environment-${{ steps.date.outputs.date }}
-          create-args: >-
-            python=3.13
-            gmt=6.5.0
-            ghostscript=10.04.0
-            numpy
-            pandas
-            xarray
-            netCDF4
-            packaging
-            contextily
-            geopandas
-            ipython
-            pyarrow-core
-            rioxarray
-            make
-            pip
-            python-build
-            geodatasets
-            myst-nb
-            panel
-            sphinx>=6.2
-            sphinx-autodoc-typehints
-            sphinx-copybutton
-            sphinx-design
-            sphinx-gallery
-            sphinx_rtd_theme
-            cairosvg
-            sphinxcontrib-svg2pdfconverter
-            tectonic
-
-      # Download cached remote files (artifacts) from GitHub
-      - name: Download remote data from GitHub
-        run: |
-          # Download cached files to ~/.gmt directory and list them
-          gh run download --name gmt-cache --dir ~/.gmt/
-          # Change modification times of the two files, so GMT won't refresh it
-          touch ~/.gmt/gmt_data_server.txt ~/.gmt/gmt_hash_server.txt
-          ls -lhR ~/.gmt
-        env:
-          GH_TOKEN: ${{ github.token }}
-
-      # Install the package that we want to test
-      - name: Install the package
-        run: |
-          python -m build --sdist
-          python -m pip install dist/*
-
-      - name: Build the HTML documentation
-        run: make -C doc clean html
-
-      - name: Build the PDF documentation
-        run:  make -C doc pdf
+          os: ${{ matrix.os }}
 
       - name: Create the HTML ZIP archive and rename the PDF file
         run: |