Guide

Quick Start

Installation

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

Hello, World!

Create server.go

package main
import (
    "net/http"
    "github.com/labstack/echo/v4"
)
func main() {
    e := echo.New()
    e.GET("/", func(c echo.Context) error {
        return c.String(http.StatusOK, "Hello, World!")
    })
    e.Logger.Fatal(e.Start(":1323"))
}

Start server

$ go run server.go

Browse to http://localhost:1323 and you should seeHello, 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

// 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 protected]" http://localhost:1323/save
// => name:Joe Smith, email:[email protected]

Form multipart/form-data

POST /save

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 "[email protected]/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, xml, form or query payload into Go struct based on Content-Typerequest header.
• Render response as json or xml with status code.

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

Serve 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, c echo.Context) (bool, error) {
  if username == "joe" && password == "secret" {
    return true, nil
  }
  return false, nil
}))
// 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)