Document a REST API with an OpenAPI 3.0 specification.
- Code, not configuration.
- No magic comments, tags, or decorators.
- Use with or without a Go web framework.
- Populates schema automatically using reflection.
- Add OpenAPI documentation to an API.
- Create a
swagger.json
orswagger.yaml
file.
- Create a
- Serve the Swagger UI to customers.
See the ./examples directory for complete examples.
// Configure the models.
api := rest.NewAPI("messages")
api.StripPkgPaths = []string{"github.com/a-h/rest/example", "github.com/a-h/respond"}
api.RegisterModel(rest.ModelOf[respond.Error](), rest.WithDescription("Standard JSON error"), func(s *openapi3.Schema) {
status := s.Properties["statusCode"]
status.Value.WithMin(100).WithMax(600)
})
api.Get("/topic/{id}").
HasPathParameter("id", rest.PathParam{
Description: "id of the topic",
Regexp: `\d+`,
}).
HasResponseModel(http.StatusOK, rest.ModelOf[models.Topic]()).
HasResponseModel(http.StatusInternalServerError, rest.ModelOf[respond.Error]())
// Create the specification.
spec, err := api.Spec()
if err != nil {
log.Fatalf("failed to create spec: %v", err)
}
// Write to stdout.
enc := json.NewEncoder(os.Stdout)
enc.SetIndent("", " ")
enc.Encode(spec)
// Create routes.
router := http.NewServeMux()
router.Handle("/topics", &get.Handler{})
router.Handle("/topic", &post.Handler{})
api := rest.NewAPI("messages")
api.StripPkgPaths = []string{"github.com/a-h/rest/example", "github.com/a-h/respond"}
// Register the error type with customisations.
api.RegisterModel(rest.ModelOf[respond.Error](), rest.WithDescription("Standard JSON error"), func(s *openapi3.Schema) {
status := s.Properties["statusCode"]
status.Value.WithMin(100).WithMax(600)
})
api.Get("/topics").
HasResponseModel(http.StatusOK, rest.ModelOf[get.TopicsGetResponse]()).
HasResponseModel(http.StatusInternalServerError, rest.ModelOf[respond.Error]())
api.Post("/topic").
HasRequestModel(rest.ModelOf[post.TopicPostRequest]()).
HasResponseModel(http.StatusOK, rest.ModelOf[post.TopicPostResponse]()).
HasResponseModel(http.StatusInternalServerError, rest.ModelOf[respond.Error]())
// Create the spec.
spec, err := api.Spec()
if err != nil {
log.Fatalf("failed to create spec: %v", err)
}
// Apply any global customisation.
spec.Info.Version = "v1.0.0."
spec.Info.Description = "Messages API"
// Attach the Swagger UI handler to your router.
ui, err := swaggerui.New(spec)
if err != nil {
log.Fatalf("failed to create swagger UI handler: %v", err)
}
router.Handle("/swagger-ui", ui)
router.Handle("/swagger-ui/", ui)
// And start listening.
fmt.Println("Listening on :8080...")
fmt.Println("Visit https://localhost:8080/swagger-ui to see API definitions")
fmt.Println("Listening on :8080...")
http.ListenAndServe(":8080", router)
go test ./...
Dir: ./examples/stdlib
go run main.go