dart_openapi_generator

Reads an OpenAPI 3.x spec (YAML or JSON, local file or HTTPS URL) and generates idiomatic Dio-based model classes and API client services via build_runner. No JVM. No Mustache. Generated code looks like a developer wrote it by hand.

Features

• Generates final class model classes with fromJson, toJson, copyWith, ==, and hashCode
• Generates Dart enum types with fromJson/toJson switch expressions
• Generates sealed class hierarchies for oneOf schemas with a discriminator
• Flattens allOf schemas into a single merged class
• Handles additionalProperties (typed or untyped)
• Generates Dio-based service classes from OpenAPI paths — one file per tag
• Generates an aggregator client class with static auth-helper factories (Bearer, API key header/query, HTTP Basic)
• Supports LocalSpec (local YAML/JSON file) and RemoteSpec (HTTPS URL with optional request headers)
• MD5-keyed cache — skips unchanged specs for fast incremental builds
• Supports OpenAPI 3.0, 3.1, and 3.2 (including in: querystring and additionalOperations)
• Zero runtime dependencies in the consumer's tree — dart_openapi_generator is a dev dependency

Installation

dependencies:
  dart_openapi_generator_annotations: ^0.1.0
  dio: ^5.0.0

dev_dependencies:
  dart_openapi_generator: ^0.1.0
  build_runner: ^2.4.0

Get Started

Follow the Getting Started guide to go from zero to a working API client.

See the Annotation Reference for every @OpenApiGenerator field.