From 7a547d79c3cbd345999f128215d856e96a45ac85 Mon Sep 17 00:00:00 2001
From: Russell Martin <russell@rjm.li>
Date: Fri, 9 Aug 2024 15:57:14 -0400
Subject: [PATCH] Refactor PR Body regexing into independent GH Action

---
 .github/actions/app-create/action.yml        | 54 +++++++++-----------
 .github/actions/install-briefcase/action.yml | 51 +++++++++---------
 .github/actions/pr-body-parse/action.yml     | 37 ++++++++++++++
 3 files changed, 83 insertions(+), 59 deletions(-)
 create mode 100644 .github/actions/pr-body-parse/action.yml

diff --git a/.github/actions/app-create/action.yml b/.github/actions/app-create/action.yml
index 7ba5a2c7..74098929 100644
--- a/.github/actions/app-create/action.yml
+++ b/.github/actions/app-create/action.yml
@@ -26,46 +26,38 @@ outputs:
 runs:
   using: composite
   steps:
-    - name: Briefcase Template Override
-      id: template-override
-      env:
-        GITHUB_TOKEN: ${{ github.token }}
+    - name: Check for Briefcase Template Repo Override
+      id: template-repo-override
+      uses: ./beeware-.github/.github/actions/pr-body-parse
+      with:
+        key-regex: 'BRIEFCASE[-_]*TEMPLATE[-_]*REPO'
+        testing-pr-body: ${{ inputs.testing-pr-body }}
+
+    - name: Check for Briefcase Template Ref Override
+      id: template-ref-override
+      uses: ./beeware-.github/.github/actions/pr-body-parse
+      with:
+        key-regex: 'BRIEFCASE[-_]*TEMPLATE[-_]*REF'
+        testing-pr-body: ${{ inputs.testing-pr-body }}
+
+    - name: Declare Briefcase Template
+      id: template
       shell: bash
       run: |
-        # Check Body of PR for template to use
-        # (only PRs will have a value for github.event.pull_request.number)
-        PR_BODY="${{ inputs.testing-pr-body }}"
-        if [[ -z "${PR_BODY}" && -n "${{ github.event.pull_request.number }}" ]]; then
-          PR_BODY=$(gh api repos/${{ github.repository }}/pulls/${{ github.event.pull_request.number }} --jq '.body')
-        fi
-        printf "::group::Retrieved PR Body\n%s\n::endgroup::\n" "${PR_BODY}"
-
-        TEMPLATE_REPO=$(printf "%s" "${PR_BODY}" | perl -wlne '/BRIEFCASE[-_]*TEMPLATE[-_]*REPO:\s*\K\S+/i and print $&')
-        TEMPLATE_REF=$(printf "%s" "${PR_BODY}" | perl -wlne '/BRIEFCASE[-_]*TEMPLATE[-_]*REF:\s*\K\S+/i and print $&')
+        REPO="${{ steps.template-repo-override.outputs.extracted-value || inputs.briefcase-template-source }}"
+        REF="${{ steps.template-ref-override.outputs.extracted-value || inputs.briefcase-template-branch }}"
 
-        # If a template is not in the PR, use inputs specified in CI workflow
-        if [ -z "${TEMPLATE_REPO}" ]; then
-          TEMPLATE_REPO="${{ inputs.briefcase-template-source }}"
+        if [ -n "${REPO}" ]; then
+          printf -- "repo=--template '%q'\n" "${REPO}" | tee -a ${GITHUB_OUTPUT}
         fi
-        if [ -z "${TEMPLATE_REF}" ]; then
-          TEMPLATE_REF="${{ inputs.briefcase-template-branch }}"
+        if [ -n "${REF}" ]; then
+          printf -- "ref=--template-branch '%q'\n" "${REF}" | tee -a ${GITHUB_OUTPUT}
         fi
 
-        # Expose template repo and branch via outputs
-        echo "repo=${TEMPLATE_REPO}" | tee -a ${GITHUB_OUTPUT}
-        echo "ref=${TEMPLATE_REF}" | tee -a ${GITHUB_OUTPUT}
-
     - name: Create Briefcase Project
       id: create
       shell: bash
       run: |
-        if [[ "${{ steps.template-override.outputs.repo }}" != "" ]]; then
-          TEMPLATE=$(printf -- "--template %q" "${{ steps.template-override.outputs.repo }}")
-        fi
-        if [[ "${{ steps.template-override.outputs.ref }}" != "" ]]; then
-          TEMPLATE_BRANCH=$(printf -- "--template-branch %q" "${{ steps.template-override.outputs.ref }}")
-        fi
-
         # Map GUI toolkit through case insensitivity
         case "$(tr '[:upper:]' '[:lower:]' <<< "${{ inputs.framework }}")" in
           toga    ) BOOTSTRAP=Toga ;;
@@ -89,7 +81,7 @@ runs:
         rm -rf "${APP_DIR}"
 
         # Roll out the project
-        briefcase new --no-input ${TEMPLATE} ${TEMPLATE_BRANCH} \
+        briefcase new --no-input ${{ steps.template.outputs.repo }} ${{ steps.template.outputs.ref }} \
           -Q "formal_name=${APP_NAME}" \
           -Q "app_name=${APP_DIR}" \
           -Q "bootstrap=${BOOTSTRAP}"
diff --git a/.github/actions/install-briefcase/action.yml b/.github/actions/install-briefcase/action.yml
index 8de59741..84ae4d28 100644
--- a/.github/actions/install-briefcase/action.yml
+++ b/.github/actions/install-briefcase/action.yml
@@ -32,38 +32,33 @@ outputs:
 runs:
   using: composite
   steps:
-    - name: Use Specified Briefcase Version
-      id: briefcase-override
-      env:
-        GITHUB_TOKEN: ${{ github.token }}
+    - name: Check for Briefcase Repo Override
+      id: briefcase-repo-override
+      uses: ./beeware-.github/.github/actions/pr-body-parse
+      with:
+        key-regex: 'BRIEFCASE[-_]*REPO'
+        testing-pr-body: ${{ inputs.testing-pr-body }}
+
+    - name: Check for Briefcase Ref Override
+      id: briefcase-ref-override
+      uses: ./beeware-.github/.github/actions/pr-body-parse
+      with:
+        key-regex: 'BRIEFCASE[-_]*REF'
+        testing-pr-body: ${{ inputs.testing-pr-body }}
+
+    - name: Declare Briefcase Source
+      id: briefcase
       shell: bash
       run: |
-        # Check Body of PR for Briefcase version to use
-        # (only PRs will have a value for github.event.pull_request.number)
-        PR_BODY="${{ inputs.testing-pr-body }}"
-        if [[ -z "${PR_BODY}" && -n "${{ github.event.pull_request.number }}" ]]; then
-          PR_BODY=$(gh api repos/${{ github.repository }}/pulls/${{ github.event.pull_request.number }} --jq '.body')
-        fi
-        printf "::group::Retrieved PR Body\n%s\n::endgroup::\n" "${PR_BODY}"
-
-        BRIEFCASE_REPO=$(printf "%s" "${PR_BODY}" | perl -wlne '/BRIEFCASE[-_]*REPO:\s*\K\S+/i and print $&')
-        BRIEFCASE_REF=$(printf "%s" "${PR_BODY}" | perl -wlne '/BRIEFCASE[-_]*REF:\s*\K\S+/i and print $&')
-
-        # If a version is not in the PR, use inputs specified in CI workflow
-        if [ -z "${BRIEFCASE_REPO}" ]; then
-          BRIEFCASE_REPO="${{ inputs.briefcase-url }}"
-        fi
-        if [ -z "${BRIEFCASE_REF}" ]; then
-          BRIEFCASE_REF="${{ inputs.briefcase-override-version }}"
-        fi
+        REPO="${{ steps.briefcase-repo-override.outputs.extracted-value || inputs.briefcase-url }}"
+        REF="${{ steps.briefcase-ref-override.outputs.extracted-value || inputs.briefcase-override-version }}"
 
-        # Expose repo and version via outputs
-        echo "repo=${BRIEFCASE_REPO}" | tee -a ${GITHUB_OUTPUT}
-        echo "ref=${BRIEFCASE_REF}" | tee -a ${GITHUB_OUTPUT}
+        printf -- "repo=%s\n" "${REPO}" | tee -a ${GITHUB_OUTPUT}
+        printf -- "ref=%s\n" "${REF}" | tee -a ${GITHUB_OUTPUT}
 
     - name: Derive Target Briefcase Version
       id: briefcase-derived
-      if: steps.briefcase-override.outputs.ref == ''
+      if: steps.briefcase.outputs.ref == ''
       shell: bash
       run: |
         # Branch or tag that triggered the workflow.
@@ -136,8 +131,8 @@ runs:
       id: install
       shell: bash
       run: |
-        REPO="${{ steps.briefcase-override.outputs.repo || inputs.briefcase-url }}"
-        REF="${{ steps.briefcase-override.outputs.ref || steps.briefcase-derived.outputs.version }}"
+        REPO="${{ steps.briefcase.outputs.repo }}"
+        REF="${{ steps.briefcase.outputs.ref || steps.briefcase-derived.outputs.version }}"
 
         echo "Installing ${REPO}@${REF}"
         python -m pip install \
diff --git a/.github/actions/pr-body-parse/action.yml b/.github/actions/pr-body-parse/action.yml
new file mode 100644
index 00000000..1b0788ea
--- /dev/null
+++ b/.github/actions/pr-body-parse/action.yml
@@ -0,0 +1,37 @@
+name: PR Body Parse
+description: Parse a value from the body of the relevant PR for a specific key
+
+inputs:
+  key-regex:
+    description: "The regex for the key identifying the value to return, e.g. BRIEFCASE[-_]*REPO"
+    required: true
+  testing-pr-body:
+    description: "Override value for body of PR; only for testing."
+    required: false
+
+outputs:
+  extracted-value:
+    value: ${{ steps.parse.outputs.extracted-value }}
+    description: "The value extracted from the PR's body for the specified key."
+
+runs:
+  using: composite
+  steps:
+    - name: Parse PR Body for ${{ inputs.key-regex }}
+      id: parse
+      env:
+        GITHUB_TOKEN: ${{ github.token }}
+      shell: bash
+      run: |
+        # Retrieve PR Body (only PRs will have a value for github.event.pull_request.number)
+        PR_BODY="${{ inputs.testing-pr-body }}"
+        if [[ -z "${PR_BODY}" && -n "${{ github.event.pull_request.number }}" ]]; then
+          PR_BODY=$(gh api repos/${{ github.repository }}/pulls/${{ github.event.pull_request.number }} --jq '.body')
+        fi
+        printf "::group::Retrieved PR Body\n%s\n::endgroup::\n" "${PR_BODY}"
+
+        # Parse value with given regex
+        EXTRACTED_VALUE=$(printf "%s" "${PR_BODY}" | perl -wlne '/${{ inputs.key-regex }}:\s*\K\S+/i and print $&')
+
+        # Expose value as output
+        echo "extracted-value=${EXTRACTED_VALUE}" | tee -a ${GITHUB_OUTPUT}