setup OSSF Scorecard workflow

Signed-off-by: Matthieu MOREL <matthieu.morel35@gmail.com>

.github/workflows/scorecard.yml

@@ -0,0 +1,56 @@
+name: Scorecard supply-chain security
+
+on:
+  # For Branch-Protection check. Only the default branch is supported. See
+  # https://github.com/ossf/scorecard/blob/main/docs/checks.md#branch-protection
+  branch_protection_rule:
+  # To guarantee Maintained check is occasionally updated. See
+  # https://github.com/ossf/scorecard/blob/main/docs/checks.md#maintained
+  schedule:
+    - cron: '22 1 * * 0'
+  push:
+    branches: [ "main" ]
+
+# Declare default permissions as read only.
+permissions: read-all
+
+jobs:
+  analysis:
+    name: Scorecard analysis
+    runs-on: ubuntu-latest
+    permissions:
+      # Needed to upload the results to code-scanning dashboard.
+      security-events: write
+      # Needed to publish results and get a badge (see publish_results below).
+      id-token: write
+      # Uncomment the permissions below if installing in a private repository.
+      # contents: read
+      # actions: read
+
+    steps:
+      - name: "Checkout code"
+        uses: actions/checkout@93ea575cb5d8a053eaa0ac8fa3b40d7e05a33cc8 # v3.1.0
+        with:
+          persist-credentials: false
+
+      - name: "Run analysis"
+        uses: ossf/scorecard-action@e38b1902ae4f44df626f11ba0734b14fb91f8f86 # v2.1.2
+        with:
+          results_file: results.sarif
+          results_format: sarif
+          publish_results: true
+
+      # Upload the results as artifacts (optional). Commenting out will disable uploads of run results in SARIF
+      # format to the repository Actions tab.
+      - name: "Upload artifact"
+        uses: actions/upload-artifact@3cea5372237819ed00197afe530f5a7ea3e805c8 # v3.1.0
+        with:
+          name: SARIF file
+          path: results.sarif
+          retention-days: 5
+
+      # Upload the results to GitHub's code scanning dashboard.
+      - name: "Upload to code-scanning"
+        uses: github/codeql-action/upload-sarif@17573ee1cc1b9d061760f3a006fc4aac4f944fd5 # v2.2.4
+        with:
+          sarif_file: results.sarif

README.md

@@ -3,6 +3,7 @@
 [![CI](https://github.com/prometheus/client_golang/actions/workflows/go.yml/badge.svg)](https://github.com/prometheus/client_golang/actions/workflows/ci.yml)
 [![Go Report Card](https://goreportcard.com/badge/github.com/prometheus/client_golang)](https://goreportcard.com/report/github.com/prometheus/client_golang)
 [![Go Reference](https://pkg.go.dev/badge/github.com/prometheus/client_golang.svg)](https://pkg.go.dev/github.com/prometheus/client_golang)
+[![OpenSSF Scorecard](https://api.securityscorecards.dev/projects/github.com/prometheus/client_golang/badge)](https://securityscorecards.dev/viewer/?uri=github.com/prometheus/client_golang)
 [![Slack](https://img.shields.io/badge/join%20slack-%23prometheus--client_golang-brightgreen.svg)](https://slack.cncf.io/)
 
 This is the [Go](http://golang.org) client library for