Add website workflows and improve ci workflow filter

This configuration mirrors OpenEXR.

Signed-off-by: Cary Phillips <[email protected]>

.github/workflows/ci_workflow.yml

@@ -1,19 +1,31 @@
 # SPDX-License-Identifier: BSD-3-Clause
-# Copyright Contributors to the OpenEXR Project.
+# Copyright (c) Contributors to the OpenEXR Project.
 #
 # GitHub Actions workflow file
 # https://help.github.com/en/actions/reference/workflow-syntax-for-github-actions
 
 name: CI
 
+# Run on all changes except:
+# - doc file changes
+# - changes to the website, since yhe website has a separate workflow
+# - changes to workflows other than this one
+
 on:
   push:
-    # Jobs are skipped when ONLY Markdown (*.md) files are changed
-    paths-ignore:
-      - '**.md'
+    paths:
+      - '**'
+      - '!**.md'
+      - '!website/**'
+      - '!.github/workflows/**'
+      - '.github/workflows/ci_workflow.yml'
   pull_request:
-    paths-ignore:
-      - '**.md'
+    paths:
+      - '**'
+      - '!**.md'
+      - '!website/**'
+      - '!.github/workflows/**'
+      - '.github/workflows/ci_workflow.yml'
 
 permissions:
   contents: read

.github/workflows/website_preview_link.yml

@@ -0,0 +1,35 @@
+# SPDX-License-Identifier: BSD-3-Clause
+# Copyright (c) Contributors to the OpenEXR Project.
+#
+# GitHub Actions workflow file
+# https://help.github.com/en/actions/reference/workflow-syntax-for-github-actions
+
+#
+# This action adds a link to the PR description pointing to the
+# readthedocs build of the website, for PRs that modify the website.
+#
+# Note that the link is also available in the PR checks, but it gets
+# buried among the output of the checks and isn't obvious.
+#
+
+name: Website preview link
+on:
+  pull_request_target:
+    types:
+      - opened
+    paths:
+      - 'website/**'
+
+permissions:
+  pull-requests: write
+
+jobs:
+  pull-request-links:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: readthedocs/actions/preview@v1
+        with:
+          project-slug: "openexr"
+          message-template: "Website preview: {docs-pr-index-url}"
+
+

.github/workflows/website_workflow.yml

@@ -0,0 +1,58 @@
+# SPDX-License-Identifier: BSD-3-Clause
+# Copyright (c) Contributors to the OpenEXR Project.
+#
+# GitHub Actions workflow file
+# https://help.github.com/en/actions/reference/workflow-syntax-for-github-actions
+
+name: Website
+
+# Run only on changes in the "website" directory or workflow file.
+# Skip the release branches, since the website is built from main.
+
+on:
+
+  push:
+    branches:-ignore:
+      - RB-*
+    paths:
+      - 'website/**'
+      - '.github/workflows/website_workflow.yml'
+
+  pull_request:
+    branches:-ignore:
+      - RB-*
+    paths:
+      - 'website/**'
+      - '.github/workflows/website_workflow.yml'
+
+permissions:
+  contents: read
+
+jobs:
+
+  Website:
+
+    # Build the website, using a process that mimics the readthedoc build.
+
+    name: 'Website'
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v3
+      - name: Create build directory
+        run: mkdir _build
+      - name: Install doxygen 
+        run: sudo apt-get install -y doxygen
+      - name: Install sphinx requirements
+        run: pip3 install -r website/requirements.txt
+      - name: Configure
+        run: cmake .. -DBUILD_WEBSITE='ON'
+        working-directory: _build
+      - name: Build
+        run: |
+          cmake --build . \
+                --target website \
+                --config Release
+        working-directory: _build
+