Huma v2 manual doc

main.go

package main

import (
	"encoding/json"
	"fmt"
	"net/http"
	"reflect"

	"github.com/danielgtaylor/huma/v2"
	"github.com/go-chi/chi/v5"
	"github.com/goccy/go-yaml"
)

func Addr[T any](value T) *T {
	return &value
}

type GreetingOutput struct {
	Message string `json:"message"`
}

func main() {
	// Create the schema registry which will hold schemas that refs can point to.
	registry := huma.NewMapRegistry("#/components/schemas/", huma.DefaultSchemaNamer)

	// Create the OpenAPI document.
	doc := huma.OpenAPI{
		OpenAPI: "3.1.0",
		Info: &huma.Info{
			Title:   "My API",
			Version: "1.0.0",
		},
		Components: &huma.Components{
			Schemas: registry,
		},
		Paths: map[string]*huma.PathItem{},
	}

	// Create a new router.
	router := chi.NewMux()

	// Manually document the route in the OpenAPI.
	doc.Paths["/greeting/{name}"] = &huma.PathItem{
		Get: &huma.Operation{
			OperationID: "get-greeting",
			Summary:     "Get a greeting",
			Parameters: []*huma.Param{
				&huma.Param{
					Name:     "name",
					In:       "path",
					Required: true,
					Schema: &huma.Schema{
						Type:        "string",
						MaxLength:   Addr(30),
						Examples:    []any{"world"},
						Description: "Name to greet",
						Extensions: map[string]interface{}{
							"x-my-custom-extension": "some value",
						},
					},
				},
			},
			Responses: map[string]*huma.Response{
				"200": &huma.Response{
					Description: "Greeting message",
					Content: map[string]*huma.MediaType{
						"application/json": &huma.MediaType{
							Schema: registry.Schema(reflect.TypeOf(GreetingOutput{}), true, ""),
						},
					},
				},
			},
		},
	}
	router.Get("/greeting/{name}", func(w http.ResponseWriter, r *http.Request) {
		name := chi.URLParam(r, "name")
		resp := &GreetingOutput{}
		resp.Message = fmt.Sprintf("Hello, %s!", name)
		b, _ := json.Marshal(resp)
		w.Header().Set("Content-Type", "application/json")
		w.Write(b)
	})

	// ...

	// Dump the OpenAPI
	b, _ := yaml.Marshal(doc)
	fmt.Println(string(b))

	// Start the server
	http.ListenAndServe("127.0.0.1:8000", router)
}