Fixes #10215

This PR adds a new --domain flag to the wrangler deploy command that allows users to deploy directly to custom domains without manually configuring routes in their wrangler.toml file.

Changes

Core Implementation:

• Added domains flag (with domain alias) to the deploy command definition
• Domain strings are automatically converted to custom domain route objects ({ pattern: domain, custom_domain: true })
• Domains are merged with existing configured routes and processed through the same validation and deployment pipeline
• Updated triggersDeploy function's Props type to accept Route[] instead of string[] for routes

User Experience:

# Deploy to a single custom domain
wrangler deploy --domain api.example.com

# Deploy to multiple custom domains  
wrangler deploy --domain api.example.com --domain app.example.com

# Combine with existing route configuration
wrangler deploy --domain api.example.com  # works alongside routes in wrangler.toml

Testing:

• Comprehensive test coverage for single/multiple domain deployment
• Tests for combining domain flags with existing route configuration
• Tests for domain validation (rejecting wildcards and paths)
• Integration with existing custom domain deployment mocks

Key Implementation Details

The --domain flag leverages the existing custom domain infrastructure by converting domain strings to the same route format that custom domains already use internally. This ensures consistency with existing validation, deployment, and error handling.

Type System Change: Updated triggersDeploy Props to accept Route[] instead of string[] for routes to support the mixed route types (string routes and custom domain route objects).

Review Focus Areas

1. Type System Impact: The change from string[] to Route[] in triggersDeploy Props - verify this doesn't break other callers
2. Domain Conversion Logic: Ensure domains are correctly converted to { pattern: domain, custom_domain: true } format
3. Route Merging: Verify that combining configured routes with domain routes works correctly
4. Test Coverage: Review test mocks for accuracy and completeness
5. Validation: Confirm that domain validation properly rejects invalid domains (wildcards, paths, etc.)

Link to Devin run: https://app.devin.ai/sessions/3f13f8ef54434b64accdb268e89f3aa1
Requested by: @petebacondarwin

• Tests
  • Tests included
  • Tests not necessary because:
• Public documentation
  • Cloudflare docs PR(s): Add --domain option to wrangler deploy cloudflare-docs#24296
  • Documentation not necessary because: This is a CLI flag addition that follows existing patterns; the flag help text provides sufficient documentation for users
• Wrangler V3 Backport
  • Wrangler PR:
  • Not necessary because: This is a new feature, not a bug fix