Pattern macros¶

drun v2 includes a comprehensive set of built-in pattern macros that provide common validation patterns without requiring complex regular expressions.

Available pattern macros¶

• semver: Basic semantic versioning (e.g., v1.2.3)
• semver_extended: Extended semantic versioning with pre-release and build metadata (e.g., v2.0.1-RC2, v1.0.0-alpha.1+build.123)
• uuid: UUID format (e.g., 550e8400-e29b-41d4-a716-446655440000)
• url: HTTP/HTTPS URL format
• ipv4: IPv4 address format (e.g., 192.168.1.1)
• slug: URL slug format (lowercase, hyphens only, e.g., my-project-name)
• docker_tag: Docker image tag format
• git_branch: Git branch name format

Usage examples¶

task "deploy" means "Deploy with validation":
  # Basic semantic versioning
  requires $version as string matching semver

  # Extended semantic versioning
  requires $release as string matching semver_extended

  # UUID validation
  requires $deployment_id as string matching uuid

  # URL validation
  requires $api_endpoint as string matching url

  # IPv4 address validation
  requires $server_ip as string matching ipv4

  # Slug validation for project names
  requires $project_slug as string matching slug

  # Docker tag validation
  requires $image_tag as string matching docker_tag

  # Git branch validation
  requires $branch as string matching git_branch

  info "Deploying {version} to {server_ip}"

Pattern macros vs raw patterns¶

Pattern macros can be used alongside raw regex patterns:

task "validation_examples":
  # Using pattern macros (recommended)
  requires $version as string matching semver
  requires $id as string matching uuid

  # Using raw patterns (for custom validation)
  requires $custom as string matching pattern "^custom-[0-9]+$"

  # Email validation (built-in)
  requires $email as string matching email format

Error messages¶

Pattern macros provide descriptive error messages:

# Semver validation error
Error: parameter 'version': value '1.2.3' does not match semver pattern (Basic semantic versioning (e.g., v1.2.3))

# UUID validation error
Error: parameter 'id': value 'not-a-uuid' does not match uuid pattern (UUID format (e.g., 550e8400-e29b-41d4-a716-446655440000))