ci: refactor set-output logic into scripts/get-prs.py

Author: consideRatio

.github/workflows/watch-dependencies.yaml

@@ -76,19 +76,16 @@ jobs:
         if: steps.local.outputs.tag != steps.latest.outputs.tag
         run: git --no-pager diff --color=always
 
-      - name: PR summary
+      - name: Fetch PR summary
         id: prsummary
         if: steps.local.outputs.tag != steps.latest.outputs.tag
         run: |
           pip install PyGithub
-
-          # We want to set multiline output, so we rely on this technique:
-          # https://docs.github.com/en/actions/using-workflows/workflow-commands-for-github-actions#multiline-strings
-          #
-          eof_randomized=EOF_$RANDOM
-          echo "prs<<$eof_randomized" >> $GITHUB_OUTPUT
-          ./scripts/get-prs.py ${{matrix.github_repo}} ${{steps.local.outputs.version}} ${{steps.latest.outputs.version}} >> $GITHUB_OUTPUT
-          echo "$eof_randomized" >> $GITHUB_OUTPUT
+          ./scripts/get-prs.py \
+              ${{matrix.github_repo}} \
+              ${{steps.local.outputs.version}} \
+              ${{steps.latest.outputs.version}} \
+              --write-github-actions-output=prs
         env:
           GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
 
@@ -208,19 +205,16 @@ jobs:
       - name: git diff
         run: git --no-pager diff --color=always
 
-      - name: PR summary
+      - name: Fetch PR summary
         id: prsummary
         if: matrix.github_repo && (steps.local.outputs.version != steps.latest.outputs.version)
         run: |
           pip install PyGithub
-
-          # We want to set multiline output, so we rely on this technique:
-          # https://docs.github.com/en/actions/using-workflows/workflow-commands-for-github-actions#multiline-strings
-          #
-          eof_randomized=EOF_$RANDOM
-          echo "prs<<$eof_randomized" >> $GITHUB_OUTPUT
-          ./scripts/get-prs.py ${{matrix.github_repo}} ${{steps.local.outputs.version}} ${{steps.latest.outputs.version}} >> $GITHUB_OUTPUT
-          echo "$eof_randomized" >> $GITHUB_OUTPUT
+          ./scripts/get-prs.py \
+              ${{matrix.github_repo}} \
+              ${{steps.local.outputs.version}} \
+              ${{steps.latest.outputs.version}} \
+              --write-github-actions-output=prs
         env:
           GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
 

scripts/get-prs.py

@@ -1,6 +1,7 @@
 #!/usr/bin/env python
 import os
 import re
+import uuid
 from argparse import ArgumentParser
 
 import github
@@ -29,6 +30,10 @@ def extract_gitref(s):
 parser.add_argument("repo", help="The repository in format user/repo")
 parser.add_argument("start", help="commit or image/chart version from which to start")
 parser.add_argument("end", help="commit or image/chart version to which to end")
+parser.add_argument(
+    "--write-github-actions-output",
+    help="Name of a GitHub Action's output variable to write to",
+)
 parser.add_argument(
     "--max-commits",
     type=int,
@@ -60,4 +65,16 @@ def extract_gitref(s):
     ]
 
 md = ["# PRs"] + pr_summaries + ["", f"{r.html_url}/compare/{start}...{end}"]
-print("\n".join(md))
+md = "\n".join(md)
+
+if args.write_github_actions_output:
+    # GitHub Actions docs on setting a output variable with a multiline string:
+    # https://docs.github.com/en/actions/using-workflows/workflow-commands-for-github-actions#multiline-strings
+    #
+    eof_marker = str(uuid.uuid4()).replace("-", "_")
+    with open(os.environ["GITHUB_OUTPUT"], "a") as f:
+        print(f"{args.write_github_actions_output}<<{eof_marker}", file=f)
+        print(md, file=f)
+        print(eof_marker, file=f)
+else:
+    print(md)