echo/website/content/index.md

+++ title = "Index" +++

Fast and unfancy HTTP server framework for Go (Golang).

Feature Overview

• Optimized HTTP router which smartly prioritize routes
• Build robust and scalable RESTful APIs
• Run with standard HTTP server or FastHTTP server
• Group APIs
• Extensible middleware framework
• Define middleware at root, group or route level
• Data binding for JSON, XML and form payload
• Handy functions to send variety of HTTP responses
• Centralized HTTP error handling
• Template rendering with any template engine
• Define your format for the logger
• Highly customizable

Performance

Quick Start

Installation

$ go get -u github.com/labstack/echo

Hello, World!

Create server.go

package main

import (
	"net/http"
	
	"github.com/labstack/echo"
)

func main() {
	e := echo.New()
	e.GET("/", func(c echo.Context) error {
		return c.String(http.StatusOK, "Hello, World!")
	})

	if err := e.Start(":1323"); err != nil {
		e.Logger.Fatal(err.Error())
	}
}

Start server

$ go run server.go

Browse to http://localhost:1323 and you should see Hello, World! on the page.

Routing

e.POST("/users", saveUser)
e.GET("/users/:id", getUser)
e.PUT("/users/:id", updateUser)
e.DELETE("/users/:id", deleteUser)

Path Parameters

// e.GET("/users/:id", getUser)
func getUser(c echo.Context) error {
  	// User ID from path `users/:id`
  	id := c.Param("id")
	return c.String(http.StatusOK, id)
}

Browse to http://localhost:1323/users/Joe and you should see 'Joe' on the page.

Query Parameters

/show?team=x-men&member=wolverine

//e.GET("/show", show)
func show(c echo.Context) error {
	// Get team and member from the query string
	team := c.QueryParam("team")
	member := c.QueryParam("member")
	return c.String(http.StatusOK, "team:" + team + ", member:" + member)
}

Browse to http://localhost:1323/show?team=x-men&member=wolverine and you should see 'team:x-men, member:wolverine' on the page.

Form application/x-www-form-urlencoded

POST /save

name	value
name	Joe Smith
email	joe@labstack.com

// e.POST("/save", save)
func save(c echo.Context) error {
	// Get name and email
	name := c.FormValue("name")
	email := c.FormValue("email")
	return c.String(http.StatusOK, "name:" + name + ", email:" + email)
}

Run the following command:

$ curl -F "name=Joe Smith" -F "email=joe@labstack.com" http://localhost:1323/save
// => name:Joe Smith, email:joe@labstack.com

Form multipart/form-data

POST /save

name	value
name	Joe Smith
avatar	avatar

func save(c echo.Context) error {
	// Get name
	name := c.FormValue("name")
	// Get avatar
  	avatar, err := c.FormFile("avatar")
  	if err != nil {
 		return err
 	}
 
 	// Source
 	src, err := avatar.Open()
 	if err != nil {
 		return err
 	}
 	defer src.Close()
 
 	// Destination
 	dst, err := os.Create(avatar.Filename)
 	if err != nil {
 		return err
 	}
 	defer dst.Close()
 
 	// Copy
 	if _, err = io.Copy(dst, src); err != nil {
  		return err
  	}

	return c.HTML(http.StatusOK, "<b>Thank you! " + name + "</b>")
}

Run the following command.

$ curl -F "name=Joe Smith" -F "avatar=@/path/to/your/avatar.png" http://localhost:1323/save
// => <b>Thank you! Joe Smith</b>

For checking uploaded image, run the following command.

cd <project directory>
ls avatar.png
// => avatar.png

Handling Request

• Bind JSON or XML or form payload into Go struct based on Content-Type request header.
• Render response as JSON or XML with status code.

type User struct {
	Name  string `json:"name" xml:"name" form:"name"`
	Email string `json:"email" xml:"email" form:"email"`
}

e.POST("/users", func(c echo.Context) error {
	u := new(User)
	if err := c.Bind(u); err != nil {
		return err
	}
	return c.JSON(http.StatusCreated, u)
	// or
	// return c.XML(http.StatusCreated, u)
})

Static Content

Server any file from static directory for path /static/*.

e.Static("/static", "static")

Learn More

Template Rendering

Middleware

// Root level middleware
e.Use(middleware.Logger())
e.Use(middleware.Recover())

// Group level middleware
g := e.Group("/admin")
g.Use(middleware.BasicAuth(func(username, password string) bool {
	if username == "joe" && password == "secret" {
		return true
	}
	return false
}))

// Route level middleware
track := func(next echo.HandlerFunc) echo.HandlerFunc {
	return func(c echo.Context) error {
		println("request to /users")
		return next(c)
	}
}
e.GET("/users", func(c echo.Context) error {
	return c.String(http.StatusOK, "/users")
}, track)

Built-in Middleware

Middleware	Description
[BodyLimit]({{< ref "middleware/body-limit.md">}})	Limit request body
[Logger]({{< ref "middleware/logger.md">}})	Log HTTP requests
[Recover]({{< ref "middleware/recover.md">}})	Recover from panics
[Gzip]({{< ref "middleware/gzip.md">}})	Send gzip HTTP response
[BasicAuth]({{< ref "middleware/basic-auth.md">}})	HTTP basic authentication
[JWTAuth]({{< ref "middleware/jwt.md">}})	JWT authentication
[Secure]({{< ref "middleware/secure.md">}})	Protection against attacks
[CORS]({{< ref "middleware/cors.md">}})	Cross-Origin Resource Sharing
[CSRF]({{< ref "middleware/csrf.md">}})	Cross-Site Request Forgery
[HTTPSRedirect]({{< ref "middleware/redirect.md#httpsredirect-middleware">}})	Redirect HTTP requests to HTTPS
[HTTPSWWWRedirect]({{< ref "middleware/redirect.md#httpswwwredirect-middleware">}})	Redirect HTTP requests to WWW HTTPS
[WWWRedirect]({{< ref "middleware/redirect.md#wwwredirect-middleware">}})	Redirect non WWW requests to WWW
[NonWWWRedirect]({{< ref "middleware/redirect.md#nonwwwredirect-middleware">}})	Redirect WWW requests to non WWW
[AddTrailingSlash]({{< ref "middleware/trailing-slash.md#addtrailingslash-middleware">}})	Add trailing slash to the request URI
[RemoveTrailingSlash]({{< ref "middleware/trailing-slash.md#removetrailingslash-middleware">}})	Remove trailing slash from the request URI
[MethodOverride]({{< ref "middleware/method-override.md">}})	Override request method

Third-party Middleware

Middleware	Description
echoperm	Keeping track of users, login states and permissions.
echopprof	Adapt net/http/pprof to labstack/echo.

Learn More

Next

• Head over to guide
• Browse recipes

Need help?

• Hop on to chat
• Open an issue

Support Echo

• ☆ the project
• Donate
• 🌐 spread the word
• Contribute to the project

Contribute

Use issues for everything

• Report issues
• Discuss on chat before sending a pull request
• Suggest new features or enhancements
• Improve/fix documentation

Credits

• Vishal Rana - Author
• Nitin Rana - Consultant
• Contributors

License

MIT