fix(ci): inject PR_LABELS env for PR Label automation (#3819)

* fix(parameters): make cache aware of single vs multiple calls

Signed-off-by: heitorlessa <lessa@amazon.co.uk>

* chore: cleanup, add test for single and nested

Signed-off-by: heitorlessa <lessa@amazon.co.uk>

* fix(ci): inject PR_LABELS env

Signed-off-by: heitorlessa <lessa@amazon.co.uk>

* chore: init PR_LABELS env with default to prevent failure (no labels)

Signed-off-by: heitorlessa <lessa@amazon.co.uk>

---------

Signed-off-by: heitorlessa <lessa@amazon.co.uk>

Author: heitorlessa

.github/scripts/constants.js

@@ -18,6 +18,9 @@ module.exports = Object.freeze({
     /** @type {string} */
     "PR_IS_MERGED": process.env.PR_IS_MERGED || "false",
 
+    /** @type {string} */
+    "PR_LABELS": process.env.PR_LABELS || "",
+
     /** @type {string} */
     "LABEL_BLOCK": "do-not-merge",
 

.github/scripts/label_pr_based_on_title.js

@@ -1,4 +1,4 @@
-const { PR_NUMBER, PR_TITLE } = require("./constants")
+const { PR_NUMBER, PR_TITLE, PR_LABELS } = require("./constants")
 
 module.exports = async ({github, context, core}) => {
     const FEAT_REGEX = /feat(\((.+)\))?(:.+)/
@@ -18,10 +18,9 @@ module.exports = async ({github, context, core}) => {
     }
 
     // get PR labels from env
-    const prLabels = process.env.PR_LABELS.replaceAll("\"", "").split(",");
+    const prLabels = PR_LABELS.replaceAll("\"", "").split(",");
     const labelKeys = Object.keys(labels);
 
-    // Maintenance: We should keep track of modified PRs in case their titles change
     let miss = 0;
     try {
         for (const label in labels) {

.github/workflows/label_pr_on_title.yml

@@ -56,6 +56,7 @@ jobs:
         env:
           PR_NUMBER: ${{ needs.get_pr_details.outputs.prNumber }}
           PR_TITLE: ${{ needs.get_pr_details.outputs.prTitle }}
+          PR_LABELS: ${{ needs.get_pr_details.outputs.prLabels }}
         with:
           github-token: ${{ secrets.GITHUB_TOKEN }}
           # This safely runs in our base repo, not on fork