Merge pull request eclipse-kapua#3817 from Agnul97/fix-sonarCloudOnForks

FIX - introduction of sonarCloud scans for pullrequests coming from external forks

.github/workflows/prNumberUploader.yaml

@@ -0,0 +1,19 @@
+name: pr-number-uploader
+on: [pull_request] # Triggers the workflow on pull request events
+
+#this workflow is used for the sonarCloud scan.
+#It saves into an artifact the pull request number.
+#In this way, then, the sonarCloud workflow (which is executed externally with respect to the context of the pr) retrieves it and performs the scan
+
+jobs:
+  uploader:
+      runs-on: ubuntu-latest
+      timeout-minutes: 5
+      steps:
+      - name: Save PR number to file for the sonarCloud scan
+        run: echo ${{ github.event.number }} > PR_NUMBER.txt
+      - name: Archive PR number
+        uses: actions/upload-artifact@v3
+        with:
+          name: PR_NUMBER
+          path: PR_NUMBER.txt

.github/workflows/sonarCloud-scan.yaml

@@ -1,34 +1,62 @@
-name: SonarCloud
-on:
-  push:
-    branches:
-      - 'develop'
-      - 'release-**'
-  pull_request:
-    types: [opened, synchronize, reopened]
+name: Sonar
 
-env:
-  GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}  # Needed to get PR information, if any
-  SONAR_TOKEN: ${{ secrets.SONAR_TOKEN }}
+on:
+  workflow_run:
+    workflows: [pr-number-uploader]
+    types: [completed]
 
 jobs:
-  scan:
+  sonar:
     name: Scan code with sonarCould
     runs-on: ubuntu-latest
+    if: ${{ github.event.workflow_run.conclusion == 'success' }}
     steps:
-      - uses: actions/checkout@v3
+      - name: Download PR number artifact
+        uses: dawidd6/action-download-artifact@v2
         with:
-          fetch-depth: 0  # Shallow clones should be disabled for a better relevancy of analysis
-      - name: Set up JDK 11
-        uses: actions/setup-java@v3
+          workflow: prNumberUploader.yaml
+          run_id: ${{ github.event.workflow_run.id }}
+          name: PR_NUMBER
+      - name: Read PR_NUMBER.txt
+        id: pr_number
+        uses: juliangruber/read-file-action@v1
         with:
-          java-version: 11
-          distribution: 'zulu'
-      - name: Cache SonarCloud packages
-        uses: actions/cache@v3
+          path: ./PR_NUMBER.txt
+      - name: Request GitHub API for PR data
+        uses: octokit/request-action@v2.x
+        id: get_pr_data
         with:
-          path: ~/.sonar/cache
-          key: ${{ runner.os }}-sonar
-          restore-keys: ${{ runner.os }}-sonar
-      - name: SonarCloud scan
-        run: mvn -B compile org.sonarsource.scanner.maven:sonar-maven-plugin:sonar -Dsonar.projectKey=org.eclipse_kapua -Dsonar.organization=eclipse
+          route: GET /repos/{full_name}/pulls/{number}
+          number: ${{ steps.pr_number.outputs.content }}
+          full_name: ${{ github.event.repository.full_name }}
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+      - name: Checkout into the pr's branch
+        uses: actions/checkout@v3
+        with:
+          repository: ${{ github.event.workflow_run.head_repository.full_name }}
+          ref: ${{ github.event.workflow_run.head_branch }}
+          fetch-depth: 0
+      - name: Fetch base branch from upstream #step needed to calculate the "new lines of code metric" for the scan. Basically, the idea is to synch. with the base branch on the upstream because the fork could be not synched with it
+        run: |
+          git remote add upstream ${{ github.event.repository.clone_url }}
+          git fetch upstream
+          git checkout -B ${{ fromJson(steps.get_pr_data.outputs.data).base.ref }} upstream/${{ fromJson(steps.get_pr_data.outputs.data).base.ref }}
+          git checkout ${{ github.event.workflow_run.head_branch }}
+          git clean -ffdx && git reset --hard HEAD
+      - uses: actions/setup-java@v3
+        with:
+          distribution: 'zulu'
+          java-version: 11
+      - name: SonarCloud Scan
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+          SONAR_TOKEN: ${{ secrets.SONAR_TOKEN }}
+        run: mvn -B compile org.sonarsource.scanner.maven:sonar-maven-plugin:sonar
+          -Dsonar.projectKey=org.eclipse_kapua
+          -Dsonar.organization=eclipse
+          -Dsonar.host.url=https://sonarcloud.io
+          -Dsonar.scm.revision=${{ github.event.workflow_run.head_sha }}
+          -Dsonar.pullrequest.key=${{ fromJson(steps.get_pr_data.outputs.data).number }}
+          -Dsonar.pullrequest.branch=${{ fromJson(steps.get_pr_data.outputs.data).head.ref }}
+          -Dsonar.pullrequest.base=${{ fromJson(steps.get_pr_data.outputs.data).base.ref }}