GCP URL Map Builder

NetworkingGCP

Build URL map routing configurations for HTTP(S) load balancers with host rules and path matchers.

Last verified: May 2026

URL Maps Configuration

Build URL map routing configurations for HTTP(S) load balancers with host rules, path matchers, and weighted traffic splitting.

Required Fields

namedefaultServicehostRulespathMatchers

{
  "name": "prod-url-map",
  "description": "Production URL map for HTTP(S) load balancer",
  "defaultService": "projects/my-project/global/backendServices/web-backend",
  "hostRules": [
    {
      "hosts": ["api.example.com"],
      "pathMatcher": "api-paths"
    },
    {
      "hosts": ["static.example.com"],
      "pathMatcher": "static-paths"
    }
  ],
  "pathMatchers": [
    {
      "name": "api-paths",
      "defaultService": "projects/my-project/global/backendServices/api-backend",
      "pathRules": [
        {
          "paths": ["/v1/*"],
          "service": "projects/my-project/global/backendServices/api-v1-backend"
        },
        {
          "paths": ["/v2/*"],
          "service": "projects/my-project/global/backendServices/api-v2-backend"
        },
        {
          "paths": ["/health"],
          "service": "projects/my-project/global/backendServices/health-backend"
        }
      ],
      "routeRules": [
        {
          "priority": 1,
          "matchRules": [
            {
              "prefixMatch": "/v2/",
              "headerMatches": [
                {
                  "headerName": "X-Canary",
                  "exactMatch": "true"
                }
              ]
            }
          ],
          "routeAction": {
            "weightedBackendServices": [
              {
                "backendService": "projects/my-project/global/backendServices/api-v2-canary",
                "weight": 100
              }
            ]
          }
        }
      ]
    },
    {
      "name": "static-paths",
      "defaultService": "projects/my-project/global/backendBuckets/static-bucket"
    }
  ],
  "tests": [
    {
      "host": "api.example.com",
      "path": "/v1/users",
      "service": "projects/my-project/global/backendServices/api-v1-backend"
    }
  ]
}

Generated Output

Output will appear here...

How It Helps

Build URL map routing configurations for HTTP(S) load balancers with host rules and path matchers. This tool helps GCP engineers generate valid configurations quickly without consulting documentation, reducing errors and accelerating infrastructure deployment. All processing runs in your browser with no data sent to external servers.

Things Engineers Ask

How does this URL Map builder keep up with new GCP features?

The URL Map options surface what is currently documented in the Google Cloud reference for that service. When Google adds a new property or value, we add it here after verifying the schema in a real project. If a recently-announced feature is not yet selectable, treat that as a 'not yet supported' signal rather than an opinion that it should not be used.

Does this URL Map builder consider the IAM permissions needed to apply the configuration?

No — generating a URL Map configuration is independent of the IAM roles required to apply it. Apply the output with a principal that has the documented permissions for that service. For least-privilege scoping, GCP's Policy Intelligence and the Role Recommender produce permission lists scoped to actual usage.

In Practice

Your team is consolidating 5 microservice load balancers behind a single global HTTPS load balancer for cost reduction (1 LB instead of 5 = $20/month saved + simpler DNS). The builder generates a URL map: host rules for each service's domain → path matcher → backend service NEG. Add HTTP→HTTPS redirect for compliance, /old-api/* → /api/v2/* rewrites for legacy clients. End-to-end consolidation in 1 day; ongoing operational burden drops to managing 1 LB instead of 5.

Practical Applications

1Producing a URL Map starting point for a new service that follows the Google Cloud reference architecture rather than copy-paste from another team's repo.
2Pre-flighting a URL Map change against a change-management ticket so the implementation matches what was approved.
3Building a URL Map reference implementation for a partner integration where you cannot rely on console access.
4Drafting a URL Map change for a Terraform or Config Connector module before raising the pull request, so reviewers see intent in plain text.

Behind the Scenes

The builder constructs URL Map configurations: URL map resource (name, default service for unmatched), host_rules (matching specific hosts), path_matchers (with default service + path rules with route actions: weighted backends, URL rewrites, redirects, retries), and header rules (for header-based routing). Output is generated as gcloud compute url-maps commands and Terraform google_compute_url_map resources.

Things the Docs Don’t Tell You

TIP

URL maps route requests to backend services based on host + path patterns. The order of pathRules matters — first match wins. Always place MORE specific patterns first (`/api/v1/users` before `/api/v1/*` before `/api/*` before `/*`).

TIP

Use URL rewrite + redirect actions for SEO and UX. Common patterns: redirect HTTP to HTTPS (set in load balancer, not URL map), redirect non-canonical hosts (example.com → www.example.com), rewrite legacy paths to new structure (/old-product/* → /products/*).

TIP

Header-based routing in URL maps enables sophisticated patterns: route mobile users to a mobile-optimized backend by inspecting User-Agent, route premium customers based on a custom header, A/B test by routing X% based on a hash header. Don't push this logic into application code if URL maps can handle it.

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