Echo

Echo Web Framework

Echo is a high-performance, minimalist Go web framework for building robust REST APIs and web applications with simplicity and efficiency.

Installation

Initialize a Go module and install Echo v4:

mkdir myapp && cd myapp
go mod init myapp
go get github.com/labstack/echo/v4

For Go v1.14 or earlier, enable module mode explicitly:

GO111MODULE=on go get github.com/labstack/echo/v4

Quick Start

Hello World Server

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"))
}

Run with go run server.go and visit http://localhost:1323.

Routing

Basic Routes

Define routes using HTTP methods (GET, POST, PUT, DELETE, PATCH, etc.):

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

Path Parameters

Extract dynamic segments from URL paths:

func getUser(c echo.Context) error {
	id := c.Param("id")
	return c.String(http.StatusOK, id)
}

Query Parameters

Access query string parameters:

func show(c echo.Context) error {
	team := c.QueryParam("team")
	member := c.QueryParam("member")
	return c.String(http.StatusOK, "team:" + team + ", member:" + member)
}

Request Handling

Bind Request Data

Echo supports automatic binding of JSON, XML, form, and query data into Go structs:

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)
})

Form Data

Handle application/x-www-form-urlencoded requests:

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

File Uploads

Handle multipart form data with file uploads:

func save(c echo.Context) error {
	name := c.FormValue("name")
	avatar, err := c.FormFile("avatar")
	if err != nil {
		return err
	}

	src, err := avatar.Open()
	if err != nil {
		return err
	}
	defer src.Close()

	dst, err := os.Create(avatar.Filename)
	if err != nil {
		return err
	}
	defer dst.Close()

	if _, err = io.Copy(dst, src); err != nil {
		return err
	}

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

Response Handling

JSON and XML Responses

Send structured data as JSON or XML:

e.GET("/users", func(c echo.Context) error {
	u := &User{
		Name:  "Jon",
		Email: "[email protected]",
	}
	return c.JSON(http.StatusOK, u)
	// or
	// return c.XML(http.StatusOK, u)
})

Pretty-Printed JSON

Format JSON responses for readability:

return c.JSONPretty(http.StatusOK, u, "  ")

Static Files

Serve Directory

Map a URL path to a local directory:

e.Static("/static", "assets")
e.Static("/", "public")  // serve from root

Serve Single File

Serve individual files:

e.File("/", "public/index.html")
e.File("/favicon.ico", "images/favicon.ico")

Embedded Filesystem (SPA)

Serve Single Page Application assets from embedded Go filesystem:

//go:embed web
var webAssets embed.FS

func main() {
	e := echo.New()

	e.Use(middleware.StaticWithConfig(middleware.StaticConfig{
		HTML5:      true,
		Root:       "web",
		Filesystem: http.FS(webAssets),
	}))

	api := e.Group("/api")
	api.GET("/users", func(c echo.Context) error {
		return c.String(http.StatusOK, "users")
	})

	if err := e.Start(":8080"); err != nil && !errors.Is(err, http.ErrServerClosed) {
		log.Fatal(err)
	}
}

Middleware

Middleware intercepts requests at root, group, or route levels:

Root-Level Middleware

Applied to all routes:

e.Use(middleware.Logger())
e.Use(middleware.Recover())

Group-Level Middleware

Applied to specific route groups:

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

Applied to individual routes:

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)

Server Startup

HTTP Server

func main() {
	e := echo.New()
	// add middleware and routes...
	if err := e.Start(":8080"); err != http.ErrServerClosed {
		log.Fatal(err)
	}
}

HTTPS/TLS Server

if err := e.StartTLS(":8443", "server.crt", "server.key"); err != http.ErrServerClosed {
	log.Fatal(err)
}

HTTP/2 Server

if err := e.StartTLS(":1323", "cert.pem", "key.pem"); err != http.ErrServerClosed {
	log.Fatal(err)
}

HTTP/2 Cleartext (H2C)

s := &http2.Server{
	MaxConcurrentStreams: 250,
	MaxReadFrameSize:     1048576,
	IdleTimeout:          10 * time.Second,
}
if err := e.StartH2CServer(":8080", s); err != http.ErrServerClosed {
	log.Fatal(err)
}

Custom HTTP Server

For advanced configuration:

s := http.Server{
	Addr:    ":8080",
	Handler: e,
	//ReadTimeout: 30 * time.Second,
}
if err := s.ListenAndServe(); err != http.ErrServerClosed {
	log.Fatal(err)
}

Advanced Features

Session Management

Use session middleware for maintaining user state:

import "github.com/labstack/echo-contrib/session"
import "github.com/gorilla/sessions"

func main() {
	e := echo.New()
	e.Use(session.Middleware(sessions.NewCookieStore([]byte("secret"))))

	e.GET("/create-session", func(c echo.Context) error {
		sess, _ := session.Get("session", c)
		sess.Values["foo"] = "bar"
		sess.Save(c.Request(), c.Response())
		return c.NoContent(http.StatusOK)
	})

	e.GET("/read-session", func(c echo.Context) error {
		sess, _ := session.Get("session", c)
		return c.String(http.StatusOK, fmt.Sprintf("foo=%v", sess.Values["foo"]))
	})

	e.Start(":8080")
}

Prometheus Metrics

Integrate Prometheus monitoring:

import "github.com/labstack/echo-contrib/echoprometheus"

func main() {
	e := echo.New()
	e.Use(echoprometheus.NewMiddleware("myapp"))
	e.GET("/metrics", echoprometheus.NewHandler())

	e.GET("/hello", func(c echo.Context) error {
		return c.String(http.StatusOK, "hello")
	})

	e.Start(":8080")
}

Request Logger with Zap

Configure structured logging:

import "go.uber.org/zap"

logger, _ := zap.NewProduction()
e.Use(middleware.RequestLoggerWithConfig(middleware.RequestLoggerConfig{
	LogURI:    true,
	LogStatus: true,
	LogValuesFunc: func(c echo.Context, v middleware.RequestLoggerValues) error {
		logger.Info("request",
			zap.String("URI", v.URI),
			zap.Int("status", v.Status),
		)
		return nil
	},
}))

Route Export

Export all registered routes as JSON:

routes := e.Routes()
// Each route contains Method, Path, and Name

Key Echo Methods

Context Methods: c.Param(), c.QueryParam(), c.FormValue(), c.FormFile(), c.Bind(), c.String(), c.JSON(), c.XML(), c.HTML(), c.File(), c.Redirect(), c.NoContent()

Echo Methods: e.GET(), e.POST(), e.PUT(), e.DELETE(), e.Static(), e.File(), e.Group(), e.Use(), e.Start(), e.StartTLS(), e.Routes()

Best Practices

• Use middleware for cross-cutting concerns (logging, auth, CORS)
• Bind request data to typed structs for safety
• Return appropriate HTTP status codes
• Group related routes for shared middleware
• Use echo.Context for request/response manipulation
• Handle errors explicitly and return meaningful responses
• Leverage middleware ecosystem for common features (JWT, CORS, compression, etc.)