[size-report] migrate to GitHub Actions (#11681)

.github/workflows/size.yml

@@ -32,7 +32,7 @@ on:
   push:
     branches-ignore:
       - 'dependabot/**'
-  pull_request:
+  pull_request_target:
     branches:
       - 'main'
 
@@ -40,12 +40,11 @@ concurrency:
   group: ${{ github.workflow }}-${{ github.event.pull_request.number || (github.repository == 'openthread/openthread' && github.run_id) || github.ref }}
   cancel-in-progress: true
 
-permissions:
-  contents: read
-
 jobs:
 
   size-report:
+    permissions:
+      pull-requests: write
     runs-on: ubuntu-24.04
     steps:
     - name: Harden Runner
@@ -56,8 +55,39 @@ jobs:
     - uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4.2.2
     - name: Run
       env:
-        OT_BASE_BRANCH: "${{ github.base_ref }}"
         GITHUB_TOKEN: "${{ secrets.GITHUB_TOKEN }}"
+        PR_NUMBER: "${{ github.event.pull_request.number }}"
       run: |
         ./script/check-size
         cat /tmp/ot-size-report/report_pr >> $GITHUB_STEP_SUMMARY
+    - uses: actions/github-script@60a0d83039c74a4aee543508d2ffcb1c3799cdea
+      name: Post Report
+      if: ${{ github.event_name == 'pull_request' }}
+      id: post-report
+      with:
+        script: |
+          const fs = require('fs')
+
+          const report = fs.readFileSync('/tmp/ot-size-report/report_pr', 'utf8');
+          const params = {
+              issue_number: context.issue.number,
+              owner: context.repo.owner,
+              repo: context.repo.repo,
+              body: report,
+          }
+
+          const response = await github.rest.issues.listComments({
+            issue_number: context.issue.number,
+            owner: context.repo.owner,
+            repo: context.repo.repo,
+          });
+
+          const kMagicHeader = '<!-- Size Report of **OpenThread** -->'
+          const comment = response.data.find(comment => comment.body.startsWith(kMagicHeader))
+
+          if (comment) {
+            params.comment_id = comment.id;
+            await github.rest.issues.updateComment(params)
+          } else {
+            await github.rest.issues.createComment(params)
+          }

script/check-size

@@ -44,8 +44,7 @@ readonly OT_REPORT_FILE_TABLE
 OT_REPORT_FILE_PR="${OT_TMP_DIR}/report_pr"
 readonly OT_REPORT_FILE_TABLE
 
-OT_REPORTER="${OT_SIZE_REPORTER-}"
-readonly OT_REPORTER
+PR_NUMBER="${PR_NUMBER:-}"
 
 setup_arm_gcc_7()
 {
@@ -170,8 +169,10 @@ generate_table_header()
     } >>"${OT_REPORT_FILE_TABLE}"
 
     {
-        printf "# Size Report of **OpenThread**\n"
-        printf "Merging PR into main\n\n"
+        printf "<!-- Size Report of **OpenThread** -->\n"
+        if [[ -n $PR_NUMBER ]]; then
+            printf "> Merging #%s into %s\n\n" "${PR_NUMBER}" "${GITHUB_BASE_REF}"
+        fi
         printf "|  name  |  branch  |  text  | data  | bss  | total |\n"
         printf "| :----: | :------: | -----: | ----: | ---: | ----: |\n"
     } >>"${OT_REPORT_FILE_PR}"
@@ -181,11 +182,6 @@ generate_table_header()
         printf "|  name  |  branch  |  text  | data  | bss  | total |\n"
         printf "| :----: | :------: | -----: | ----: | ---: | ----: |\n"
     } >>"${OT_REPORT_FILE_PR}_libs"
-
-    if [ -n "${OT_REPORTER}" ]; then
-        "${OT_REPORTER}" init OpenThread
-    fi
-
 }
 
 generate_size_diff()
@@ -255,10 +251,6 @@ generate_size_diff()
         printf "| %+d | %+d | %+d | %+d |" "${size_diff[0]}" "${size_diff[1]}" "${size_diff[2]}" "${size_diff[3]}"
         printf "\n"
     } >>"${pr_report_file}"
-
-    if [ -n "${OT_REPORTER}" ]; then
-        "${OT_REPORTER}" size "${old_file}" "${new_file}"
-    fi
 }
 
 generate_report()
@@ -295,10 +287,6 @@ finalize_report()
 
     printf "</details>" >>${OT_REPORT_FILE_PR}_libs
     cat "${OT_REPORT_FILE_PR}_libs" >>${OT_REPORT_FILE_PR}
-
-    if [ -n "${OT_REPORTER}" ]; then
-        "${OT_REPORTER}" post
-    fi
 }
 
 size_nrf52840()