Add slack notification to Snapshot-CI

.github/workflows/snapshot-ci.yml

@@ -149,3 +149,89 @@ jobs:
           path: |
             powsybl-metrix/metrix-simulator/build/install/bin
             powsybl-metrix/metrix-simulator/build/install/etc
+
+      - name: Store job result
+        if: always()
+        run: |
+          echo "${{ matrix.os }}=${{ job.status }}" >> job_result_${{ matrix.os }}.txt
+
+      - name: Upload job result
+        if: always()
+        uses: actions/upload-artifact@65462800fd760344b1a7b4382951275a0abb4808 # 4.3.3
+        with:
+          name: job-results_${{ matrix.os }}
+          path: job_result_${{ matrix.os }}.txt
+
+    outputs:
+      core-version: ${{ env.CORE_VERSION }}
+      metrix-branch: ${{ env.INTEGRATION_BRANCH }}
+
+  # Slack notification on failure
+  notify_slack:
+    needs: build_powsybl_metrix
+    runs-on: ubuntu-latest
+    if: always()
+    steps:
+      - name: Determine workflow status
+        id: workflow_status
+        run: |
+          if [ "${{ job.status }}" == "success" ]; then
+            echo "icon=✅" >> $GITHUB_OUTPUT
+            echo "status=Successful" >> $GITHUB_OUTPUT
+          else
+            echo "icon=❌" >> $GITHUB_OUTPUT
+            echo "status=Failed" >> $GITHUB_OUTPUT
+          fi
+
+      - name: Download job results
+        uses: actions/download-artifact@fa0a91b85d4f404e444e00e005971372dc801d16 # v4.1.8
+
+      - name: Combine job results
+        run: |
+          for dir in job-results_*; do
+            cat "$dir"/* >> combined_job_results.txt
+          done
+
+      - name: Format job results
+        id: format_results
+        run: |
+          formatted=""
+          while IFS='=' read -r os status; do
+            icon=$([ "$status" == "success" ] && echo ":white_check_mark:" || echo ":x:")
+            formatted+="${icon} Build powsybl-metrix on *${os}*\\n"
+          done < combined_job_results.txt
+          formatted="${formatted%\\n}"  # Remove the last newline
+          echo "formatted_results=${formatted}" >> $GITHUB_OUTPUT
+
+      - name: Send Slack Notification
+        uses: 8398a7/action-slack@28ba43ae48961b90635b50953d216767a6bea486 # v3.16.2
+        with:
+          author_name: 'powsybl-metrix on GitHub'
+          status: custom
+          custom_payload: |
+            {
+              attachments: [{
+                color: '${{ job.status }}' === 'success' ? "#319f4b" : '${{ job.status }}' === 'failure' ? "#f64538" : "#ffc965",
+                "blocks": [
+                  {
+                    "type": "section",
+                    "text": {
+                      "type": "mrkdwn",
+                      "text": "${{ steps.workflow_status.outputs.icon }} *${{ steps.workflow_status.outputs.status }} workflow: Snapshot-CI on <https://github.com/powsybl/powsybl-metrix|powsybl-metrix>*\n\nBranch built: ${{ needs.build_powsybl_metrix.outputs.metrix-branch }}\nPowSyBl-Core version used: ${{ needs.build_powsybl_metrix.outputs.core-version }}"
+                    }
+                  },
+                  {
+                    "type": "divider"
+                  },
+                  {
+                    "type": "section",
+                    "text": {
+                      "type": "mrkdwn",
+                      "text": "*Workflow details:*\n\n${{ steps.format_results.outputs.formatted_results }}\n\nSee logs on <https://github.com/${{ github.repository }}/actions/runs/${{ github.run_id }}|GitHub>"
+                    }
+                  }
+                ]
+              }]
+            }
+        env:
+          SLACK_WEBHOOK_URL: ${{ secrets.SLACK_WEBHOOK_URL_METRIX }}