swag

Automatically generate RESTful API documentation with Swagger 2.0 for Go.

gopher image source is tenntenn/gopher-stickers. It has licenses creative commons licensing.

What is swag?

swag converts Go annotations to Swagger Documentation 2.0. And provides a variety of builtin web framework lib. Let you can quickly integrated in existing golang project(using Swagger UI) .

Status of implementations

Swagger 2.0 document

• Basic Structure
• API Host and Base Path
• Paths and Operations
• Describing Parameters
• Describing Request Body
• Describing Responses
• MIME Types
• Authentication
  • Basic Authentication
  • API Keys
• Adding Examples
• File Upload
• Enums
• Grouping Operations With Tags
• Swagger Extensions

Document

• web

Example

swaggo + gin

Getting started

1. Add comments to your API source code, See Declarative Comments Format

2. Download swag by using:

$ go get -u github.com/swaggo/swag/cmd/swag

3. Run the swag in project root folder which contains main.go file, The swag will parse your comments and generate required files(docs folder and docs/doc.go).

$ swag init

How to use it with gin?

This example source here.

1.After using swag to generate Swagger 2.0 docs. Import following packages:

import "github.com/swaggo/gin-swagger" // gin-swagger middleware
import "github.com/swaggo/gin-swagger/swaggerFiles" // swagger embed files

Supported Web Framework in generate swagger middleware

• gin
• echo
• net/http
• revel

2.Added General API Info annotations in main.go code:

// @title Swagger Example API
// @version 1.0
// @description This is a sample server celler server.
// @termsOfService http://swagger.io/terms/

// @contact.name API Support
// @contact.url http://www.swagger.io/support
// @contact.email support@swagger.io

// @license.name Apache 2.0
// @license.url http://www.apache.org/licenses/LICENSE-2.0.html

// @host localhost:8080
// @BasePath /api/v1

// @securityDefinitions.basic BasicAuth

// @securityDefinitions.apikey ApiKeyAuth
// @in header
// @name Authorization

// @securitydefinitions.oauth2.application OAuth2Application
// @tokenUrl https://example.com/oauth/token
// @scope.write Grants write access
// @scope.admin Grants read and write access to administrative information

// @securitydefinitions.oauth2.implicit OAuth2Implicit
// @authorizationurl https://example.com/oauth/authorize
// @scope.write Grants write access
// @scope.admin Grants read and write access to administrative information

// @securitydefinitions.oauth2.password OAuth2Password
// @tokenUrl https://example.com/oauth/token
// @scope.read Grants read access
// @scope.write Grants write access
// @scope.admin Grants read and write access to administrative information

// @securitydefinitions.oauth2.accessCode OAuth2AccessCode
// @tokenUrl https://example.com/oauth/token
// @authorizationurl https://example.com/oauth/authorize
// @scope.admin Grants read and write access to administrative information

func main() {
	r := gin.Default()

	c := controller.NewController()

	v1 := r.Group("/api/v1")
	{
		accounts := v1.Group("/accounts")
		{
			accounts.GET(":id", c.ShowAccount)
			accounts.GET("", c.ListAccounts)
			accounts.POST("", c.AddAccount)
			accounts.DELETE(":id", c.DeleteAccount)
			accounts.PATCH(":id", c.UpdateAccount)
			accounts.POST(":id/images", c.UploadAccountImage)
		}
    //...
	}
	r.GET("/swagger/*any", ginSwagger.WrapHandler(swaggerFiles.Handler))
	r.Run(":8080")
}
//...

3.Added API Operation annotations in controller code

package controller

import (
	"fmt"
	"net/http"
	"strconv"

	"github.com/gin-gonic/gin"
	"github.com/swaggo/swag/example/celler/httputil"
	"github.com/swaggo/swag/example/celler/model"
)

// ShowAccount godoc
// @Summary Show a account
// @Description get string by ID
// @ID get-string-by-int
// @Accept  json
// @Produce  json
// @Param id path int true "Account ID"
// @Success 200 {object} model.Account
// @Failure 400 {object} httputil.HTTPError
// @Failure 404 {object} httputil.HTTPError
// @Failure 500 {object} httputil.HTTPError
// @Router /accounts/{id} [get]
func (c *Controller) ShowAccount(ctx *gin.Context) {
	id := ctx.Param("id")
	aid, err := strconv.Atoi(id)
	if err != nil {
		httputil.NewError(ctx, http.StatusBadRequest, err)
		return
	}
	account, err := model.AccountOne(aid)
	if err != nil {
		httputil.NewError(ctx, http.StatusNotFound, err)
		return
	}
	ctx.JSON(http.StatusOK, account)
}

// ListAccounts godoc
// @Summary List accounts
// @Description get accounts
// @Accept  json
// @Produce  json
// @Param q query string false "name search by q"
// @Success 200 {array} model.Account
// @Failure 400 {object} httputil.HTTPError
// @Failure 404 {object} httputil.HTTPError
// @Failure 500 {object} httputil.HTTPError
// @Router /accounts [get]
func (c *Controller) ListAccounts(ctx *gin.Context) {
	q := ctx.Request.URL.Query().Get("q")
	accounts, err := model.AccountsAll(q)
	if err != nil {
		httputil.NewError(ctx, http.StatusNotFound, err)
		return
	}
	ctx.JSON(http.StatusOK, accounts)
}

//...

4.Run it, and browser to http://localhost:8080/swagger/index.html. You will see Swagger 2.0 Api documents as bellow:

About the Project

This project was inspired by swagger but simplified the usage of complexity and support a variety of web framework.