deepmap/oapi-codegen
Oapi Codegen
oapi-codegen is a suite of generators that converts OpenAPI 3 specifications into type-safe Go client libraries, server boilerplate, and data models. It provides tools for producing production-ready HTTP clients and server-side interfaces to ensure that Go implementations remain compliant with defined API contracts.
The tool supports server generation across various web frameworks and allows for extensive customization via template overrides, specification overlays, and custom type definition mappings. It handles complex API requirements through external reference resolution to organize code across multiple packages and specification overlay merging to modify definitions without altering the original source.
The project covers data modeling with specialized handling for nullable types to distinguish between missing fields and explicit null values. It also includes middleware for request validation to verify that incoming HTTP requests match the specification schemas.
Features
- API Client Generators - Generates production-ready, type-safe Go client code from OpenAPI specifications.
- Schema-to-Struct Mappers - Transforms OpenAPI JSON schemas into strongly typed Go structures with custom tags for serialization.
- OpenAPI Processors - Processes OpenAPI specifications to generate Go server boilerplate and interface definitions.
- Client Library Generation - Transforms OpenAPI specifications into functional, type-safe Go client libraries.
- Code Generators - Generates type-safe Go client and server boilerplate directly from OpenAPI 3 specifications.
- Server Boilerplate Generators - Creates server-side scaffolding and interface definitions for Go backends to accelerate API implementation.
- API Model Generators - Creates type definitions and data structures based on the schemas defined in an OpenAPI specification.
- Data Model Generators - Converts OpenAPI schemas into type-safe Go definitions and data models.
- Type-Safe Client Generators - Produces type-safe request and response handlers for Go applications based on API specifications.
- Automated Data Contracts - Automates the creation of data models and request validation logic based on a shared OpenAPI specification.
- Request Validation Middleware - Provides middleware to verify that incoming HTTP requests match the API specification schemas.
- Server Scaffolding Tools - Creates server-side interfaces and request handlers for various Go web frameworks to ensure contract compliance.
- Code Boilerplate Templates - Uses external template files to map OpenAPI specification elements into Go source code structures.
- Configuration Overlays - Updates or removes elements from a specification using an overlay file without altering the original source.
- Go Development Workflows - Accelerates the development of Go web services by generating boilerplate and handling complex type definitions.
- Nullability Constraint Enforcement - Distinguishes between omitted fields, null values, and actual data using specialized type wrappers.
- Nullability Wrappers - Implements specialized wrapper types to distinguish between missing fields and explicit null values in API responses.
- Specification Overlays - Combines a primary OpenAPI document with a secondary overlay file to modify API definitions before generation.
- Code Generators - Generates boilerplate code from OpenAPI 3.0 definitions.
- Development Tools - Generates Go client and server code from OpenAPI specs.
