Implement SSL Certificate Monitor workflow

.github/config/ssl_domains.yaml

@@ -0,0 +1,9 @@
+warning_days: 21
+domains:
+  - bazel.build
+  - bcr.bazel.build
+  - blog.bazel.build
+  - dashboard.bazel.build
+  - mirror.bazel.build
+  - registry.bazel.build
+  - releases.bazel.build

.github/scripts/check_ssl.py

@@ -0,0 +1,138 @@
+# Copyright 2026 The Bazel Authors. All rights reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#    http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+"""Script to monitor SSL certificate expiration for Bazel domains."""
+
+import datetime
+import json
+import os
+import socket
+import ssl
+import sys
+from typing import Dict, List, Optional, Tuple
+
+import certifi
+import yaml
+
+# Constants
+DEFAULT_CONFIG_PATH = os.path.join(
+    os.path.dirname(__file__), "../config/ssl_domains.yaml"
+)
+DEFAULT_WARNING_DAYS = 21
+HTTPS_PORT = 443
+SOCKET_TIMEOUT_SECONDS = 5
+
+
+class SSLMonitor:
+    """Class to manage and check SSL certificate expirations."""
+
+    def __init__(self, config_path: str = DEFAULT_CONFIG_PATH):
+        self.config_path = config_path
+        self.config = self._load_config()
+        self.warning_days = self.config.get("warning_days", DEFAULT_WARNING_DAYS)
+        self.domains = self.config.get("domains", [])
+        self.context = ssl.create_default_context(cafile=certifi.where())
+
+    def _load_config(self) -> Dict:
+        """Loads the YAML configuration file."""
+        if not os.path.exists(self.config_path):
+            print(f"Error: Config file not found at {self.config_path}")
+            sys.exit(1)
+
+        try:
+            with open(self.config_path, "r", encoding="utf-8") as f:
+                config = yaml.safe_load(f)
+                return config if isinstance(config, dict) else {}
+        except yaml.YAMLError as exc:
+            print(f"Error parsing YAML config: {exc}")
+            sys.exit(1)
+
+    def get_days_until_expiration(self, domain: str) -> int:
+        """Connects to the domain and retrieves days until certificate expiration."""
+        with socket.create_connection(
+            (domain, HTTPS_PORT), timeout=SOCKET_TIMEOUT_SECONDS
+        ) as sock:
+            with self.context.wrap_socket(sock, server_hostname=domain) as ssock:
+                cert = ssock.getpeercert()
+                if not cert:
+                    raise ValueError(f"No certificate found for {domain}")
+
+                expires_str = cert["notAfter"]
+                # Format: '%b %d %H:%M:%S %Y GMT' (e.g., 'Mar 26 20:13:28 2026 GMT')
+                expires_dt = datetime.datetime.strptime(
+                    expires_str, "%b %d %H:%M:%S %Y GMT"
+                ).replace(tzinfo=datetime.timezone.utc)
+
+                delta = expires_dt - datetime.datetime.now(datetime.timezone.utc)
+                return delta.days
+
+    def check_all(self) -> List[str]:
+        """Checks all configured domains and prints the status."""
+        failed_domains = []
+        print(f"Checking {len(self.domains)} domains (Threshold: < {self.warning_days} days)...\n")
+        print(f"{'DOMAIN':<35} | {'DAYS LEFT':<10} | {'STATUS'}")
+        print("-" * 65)
+
+        for domain in self.domains:
+            try:
+                days_left = self.get_days_until_expiration(domain)
+                status = "✅ OK"
+                if days_left < self.warning_days:
+                    status = "❌ EXPIRING SOON"
+                    failed_domains.append(f"{domain} ({days_left} days left)")
+                print(f"{domain:<35} | {days_left:<10} | {status}")
+            except (OSError, ValueError) as e:
+                # Catch broad exceptions to ensure we try all domains
+                error_msg = str(e)
+                print(f"{domain:<35} | {'ERROR':<10} | 🚨 {error_msg}")
+                failed_domains.append(f"{domain} ({error_msg})")
+
+        return failed_domains
+
+
+def report_failures(failures: List[str]):
+    """Reports failures to stdout and GitHub Step Summary if available."""
+    if not failures:
+        print("\nAll certificates look good.")
+        return
+
+    summary = "\n".join([f"- {d}" for d in failures])
+
+    # GitHub Action specific summary
+    if "GITHUB_STEP_SUMMARY" in os.environ:
+        try:
+            with open(os.environ["GITHUB_STEP_SUMMARY"], "a", encoding="utf-8") as fh:
+                fh.write("### 🚨 SSL Certificates Expiring Soon or Failing\n")
+                fh.write(summary + "\n")
+        except IOError as e:
+            print(f"Warning: Could not write to GITHUB_STEP_SUMMARY: {e}")
+
+    print("\nCRITICAL ISSUES FOUND:")
+    print(summary)
+    sys.exit(1)
+
+
+def main():
+
+    monitor = SSLMonitor()
+    if not monitor.domains:
+        print("Error: No domains found in config.")
+        sys.exit(1)
+
+    failures = monitor.check_all()
+    report_failures(failures)
+
+
+if __name__ == "__main__":
+    main()

.github/scripts/manage_ssl_issue.js

@@ -0,0 +1,64 @@
+// Copyright 2026 The Bazel Authors. All rights reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//    http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+module.exports = async ({github, context}) => {
+  const fs = require("fs");
+  const output = fs.readFileSync("ssl_output.txt", "utf8");
+  const title = "🚨 Urgent: SSL Certificates Expiring";
+
+  // Find existing open issues created by this workflow
+  const issues = await github.rest.issues.listForRepo({
+    owner: context.repo.owner,
+    repo: context.repo.repo,
+    state: "open",
+    creator: "github-actions[bot]"
+  });
+
+  const existingIssue = issues.data.find(i => i.title === title);
+  const body = [
+    "### SSL Certificate Warning",
+    "",
+    "The automated monitor has detected SSL issues.",
+    "",
+    "#### Details:",
+    "```",
+    output,
+    "```",
+    "",
+    "**Action Required:**",
+    "1. Check `.github/config/ssl_domains.yaml` to verify the domain list.",
+    "2. Renew the certificates.",
+    "",
+    `[Workflow Run Log](${context.serverUrl}/${context.repo.owner}/${context.repo.repo}/actions/runs/${context.runId})`,
+    "",
+    "cc: @bazelbuild/bazel-oss"
+  ].join("\n");
+
+  if (existingIssue) {
+    await github.rest.issues.createComment({
+      owner: context.repo.owner,
+      repo: context.repo.repo,
+      issue_number: existingIssue.number,
+      body: "SSL check failed again. Latest status:\n\n" + body
+    });
+  } else {
+    await github.rest.issues.create({
+      owner: context.repo.owner,
+      repo: context.repo.repo,
+      title: title,
+      body: body,
+      labels: ["breakage", "P0", "team-OSS", "infrastructure"]
+    });
+  }
+}

.github/workflows/ssl-monitor.yml

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+name: SSL Certificate Monitor
+
+on:
+  schedule:
+    - cron: "0 8 * * *"  # Runs daily at 08:00 UTC
+  workflow_dispatch:      # Allows manual trigger
+  pull_request:           # Validates changes to the monitor itself
+    paths:
+      - ".github/workflows/ssl-monitor.yml"
+      - ".github/scripts/check_ssl.py"
+      - ".github/scripts/manage_ssl_issue.js"
+      - ".github/config/ssl_domains.yaml"
+
+permissions:
+  contents: read
+  issues: write
+
+jobs:
+  check-ssl-certs:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout Repository
+        uses: actions/checkout@v4
+
+      - name: Set up Python
+        uses: actions/setup-python@v5
+        with:
+          python-version: "3.11"
+
+      - name: Install dependencies
+        run: pip install PyYAML certifi
+
+      - name: Run SSL Check
+        id: check_script
+        run: |
+          # Capture output to a file and set a flag if the script fails
+          python .github/scripts/check_ssl.py > ssl_output.txt 2>&1 || echo "SSL_CHECK_FAILED=true" >> $GITHUB_ENV
+          cat ssl_output.txt
+
+      - name: Manage SSL Issue on Failure
+        if: env.SSL_CHECK_FAILED == 'true'
+        uses: actions/github-script@v7
+        with:
+          script: |
+            const script = require('./.github/scripts/manage_ssl_issue.js')
+            await script({github, context})
+
+      - name: Fail workflow if SSL issues found
+        if: env.SSL_CHECK_FAILED == 'true'
+        run: |
+          echo "SSL check failed. See script output and created/updated GitHub issue."
+          exit 1