fiber README

The project's README from github.com/gofiber/fiber. As one markdown file: README.md.

Fiber
Codecov

Fiber is an Express inspired web framework built on top of Fasthttp, the fastest HTTP engine for Go. Designed to ease things up for fast development with zero memory allocation and performance in mind.

Official Sponsors

CodeRabbit

Blacksmith

Tool Sponsors - supporting Fiber with free IDE licenses and AI credits

JetBrains   OpenAI   Anthropic

⚙️ Installation

Fiber requires Go version 1.26 or higher to run. If you need to install or upgrade Go, visit the official Go download page. To start setting up your project, create a new directory for your project and navigate into it. Then, initialize your project with Go modules by executing the following command in your terminal:

go mod init github.com/your/repo

To learn more about Go modules and how they work, you can check out the Using Go Modules blog post.

After setting up your project, you can install Fiber with the go get command:

go get -u github.com/gofiber/fiber/v3

This command fetches the Fiber package and adds it to your project's dependencies, allowing you to start building your web applications with Fiber.

⚡️ Quickstart

Getting started with Fiber is easy. Here's a basic example to create a simple web server that responds with "Hello, World 👋!" on the root path. This example demonstrates initializing a new Fiber app, setting up a route, and starting the server.

package main

import (
    "log"

    "github.com/gofiber/fiber/v3"
)

func main() {
    // Initialize a new Fiber app
    app := fiber.New()

    // Define a route for the GET method on the root path '/'
    app.Get("/", func(c fiber.Ctx) error {
        // Send a string response to the client
        return c.SendString("Hello, World 👋!")
    })

    // Start the server on port 3000
    log.Fatal(app.Listen(":3000"))
}

This simple server is easy to set up and run. It introduces the core concepts of Fiber: app initialization, route definition, and starting the server. Just run this Go program, and visit http://localhost:3000 in your browser to see the message.

Zero Allocation

Fiber is optimized for high-performance, meaning values returned from fiber.Ctx are not immutable by default and will be reused across requests. As a rule of thumb, you must only use context values within the handler and must not keep any references. Once you return from the handler, any values obtained from the context will be reused in future requests. Visit our documentation to learn more.

🤖 Benchmarks

These tests are performed by TechEmpower. If you want to see all the results, please visit our Wiki.

🎯 Features

💡 Philosophy

New gophers that make the switch from Node.js to Go are dealing with a learning curve before they can start building their web applications or microservices. Fiber, as a web framework, was created with the idea of minimalism and follows the UNIX way, so that new gophers can quickly enter the world of Go with a warm and trusted welcome.

Fiber is inspired by Express, the most popular web framework on the Internet. We combined the ease of Express and raw performance of Go. If you have ever implemented a web application in Node.js (using Express or similar), then many methods and principles will seem very common to you.

We listen to our users in issues, Discord channel and all over the Internet to create a fast, flexible and friendly Go web framework for any task, deadline and developer skill! Just like Express does in the JavaScript world.

⚠️ Limitations

net/http compatibility

Fiber can run side by side with the standard library. The router accepts existing net/http handlers directly and even works with native fasthttp.RequestHandler callbacks, so you can plug in legacy endpoints without wrapping them manually:

package main

import (
    "log"
    "net/http"

    "github.com/gofiber/fiber/v3"
)

func main() {
    httpHandler := http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
        if _, err := w.Write([]byte("served by net/http")); err != nil {
            panic(err)
        }
    })

    app := fiber.New()
    app.Get("/", httpHandler)

    // Start the server on port 3000
    log.Fatal(app.Listen(":3000"))
}

When you need to convert entire applications or reuse net/http middleware chains, rely on the adaptor middleware. It converts handlers and middlewares in both directions and even lets you mount a Fiber app in a net/http server.

Express-style handlers

Fiber also adapts Express-style callbacks that operate on the lightweight fiber.Req and fiber.Res helper interfaces. This lets you port middleware and route handlers from Express-inspired codebases while keeping Fiber's router features:

// Request/response handlers (2-argument)
app.Get("/", func(req fiber.Req, res fiber.Res) error {
    return res.SendString("Hello from Express-style handlers!")
})

// Middleware with an error-returning next callback (3-argument)
app.Use(func(req fiber.Req, res fiber.Res, next func() error) error {
    if req.IP() == "192.168.1.254" {
        return res.SendStatus(fiber.StatusForbidden)
    }
    return next()
})

// Middleware with a no-arg next callback (3-argument)
app.Use(func(req fiber.Req, res fiber.Res, next func()) {
    if req.Get("X-Skip") == "true" {
        return // stop the chain without calling next
    }
    next()
})

Note: Adapted net/http handlers continue to operate with the standard-library semantics. They don't get access to fiber.Ctx features and incur the overhead of the compatibility layer, so native fiber.Handler callbacks still provide the best performance.

👀 Examples

Listed below are some of the common examples. If you want to see more code examples, please visit our Recipes repository or visit our hosted API documentation.

📖 Basic Routing

package main

import (
    "fmt"
    "log"

    "github.com/gofiber/fiber/v3"
)

func main() {
    app := fiber.New()

    // GET /api/register
    app.Get("/api/*", func(c fiber.Ctx) error {
        msg := fmt.Sprintf("✋ %s", c.Params("*"))
        return c.SendString(msg) // => ✋ register
    })

    // GET /flights/LAX-SFO
    app.Get("/flights/:from-:to", func(c fiber.Ctx) error {
        msg := fmt.Sprintf("💸 From: %s, To: %s", c.Params("from"), c.Params("to"))
        return c.SendString(msg) // => 💸 From: LAX, To: SFO
    })

    // GET /dictionary.txt
    app.Get("/:file.:ext", func(c fiber.Ctx) error {
        msg := fmt.Sprintf("📃 %s.%s", c.Params("file"), c.Params("ext"))
        return c.SendString(msg) // => 📃 dictionary.txt
    })

    // GET /john/75
    app.Get("/:name/:age/:gender?", func(c fiber.Ctx) error {
        msg := fmt.Sprintf("👴 %s is %s years old", c.Params("name"), c.Params("age"))
        return c.SendString(msg) // => 👴 john is 75 years old
    })

    // GET /john
    app.Get("/:name", func(c fiber.Ctx) error {
        msg := fmt.Sprintf("Hello, %s 👋!", c.Params("name"))
        return c.SendString(msg) // => Hello john 👋!
    })

    log.Fatal(app.Listen(":3000"))
}

📖 Route Naming

package main

import (
    "encoding/json"
    "fmt"
    "log"

    "github.com/gofiber/fiber/v3"
)

func main() {
    app := fiber.New()

    app.Get("/api/*", func(c fiber.Ctx) error {
        msg := fmt.Sprintf("✋ %s", c.Params("*"))
        return c.SendString(msg) // => ✋ register
    }).Name("api")

    route := app.GetRoute("api")

    data, _ := json.MarshalIndent(route, "", "  ")
    fmt.Println(string(data))
    // Prints:
    // {
    //    "method": "GET",
    //    "name": "api",
    //    "path": "/api/*",
    //    "params": [
    //      "*1"
    //    ]
    // }

    log.Fatal(app.Listen(":3000"))
}

📖 Serving Static Files

package main

import (
    "log"

    "github.com/gofiber/fiber/v3"
    "github.com/gofiber/fiber/v3/middleware/static"
)

func main() {
    app := fiber.New()

    // Serve static files from the "./public" directory
    app.Get("/*", static.New("./public"))
    // => http://localhost:3000/js/script.js
    // => http://localhost:3000/css/style.css

    app.Get("/prefix*", static.New("./public"))
    // => http://localhost:3000/prefix/js/script.js
    // => http://localhost:3000/prefix/css/style.css

    // Serve a single file for any unmatched routes
    app.Get("*", static.New("./public/index.html"))
    // => http://localhost:3000/any/path/shows/index.html

    log.Fatal(app.Listen(":3000"))
}

📖 Middleware & Next

package main

import (
    "fmt"
    "log"

    "github.com/gofiber/fiber/v3"
)

func main() {
    app := fiber.New()

    // Middleware that matches any route
    app.Use(func(c fiber.Ctx) error {
        fmt.Println("🥇 First handler")
        return c.Next()
    })

    // Middleware that matches all routes starting with /api
    app.Use("/api", func(c fiber.Ctx) error {
        fmt.Println("🥈 Second handler")
        return c.Next()
    })

    // GET /api/list
    app.Get("/api/list", func(c fiber.Ctx) error {
        fmt.Println("🥉 Last handler")
        return c.SendString("Hello, World 👋!")
    })

    log.Fatal(app.Listen(":3000"))
}
📚 Show more code examples

Views Engines

📖 Config 📖 Engines 📖 Render

Fiber defaults to the html/template when no view engine is set.

If you want to execute partials or use a different engine like amber, handlebars, mustache, or pug, etc., check out our Template package that supports multiple view engines.

package main

import (
    "log"

    "github.com/gofiber/fiber/v3"
    "github.com/gofiber/template/pug"
)

func main() {
    // Initialize a new Fiber app with Pug template engine
    app := fiber.New(fiber.Config{
        Views: pug.New("./views", ".pug"),
    })

    // Define a route that renders the "home.pug" template
    app.Get("/", func(c fiber.Ctx) error {
        return c.Render("home", fiber.Map{
            "title": "Homepage",
            "year":  1999,
        })
    })

    log.Fatal(app.Listen(":3000"))
}

Grouping Routes into Chains

📖 Group

package main

import (
    "log"

    "github.com/gofiber/fiber/v3"
)

func middleware(c fiber.Ctx) error {
    log.Println("Middleware executed")
    return c.Next()
}

func handler(c fiber.Ctx) error {
    return c.SendString("Handler response")
}

func main() {
    app := fiber.New()

    // Root API group with middleware
    api := app.Group("/api", middleware) // /api

    // API v1 routes
    v1 := api.Group("/v1", middleware) // /api/v1
    v1.Get("/list", handler)           // /api/v1/list
    v1.Get("/user", handler)           // /api/v1/user

    // API v2 routes
    v2 := api.Group("/v2", middleware) // /api/v2
    v2.Get("/list", handler)           // /api/v2/list
    v2.Get("/user", handler)           // /api/v2/user

    log.Fatal(app.Listen(":3000"))
}

Middleware Logger

📖 Logger

package main

import (
    "log"

    "github.com/gofiber/fiber/v3"
    "github.com/gofiber/fiber/v3/middleware/logger"
)

func main() {
    app := fiber.New()

    // Use Logger middleware
    app.Use(logger.New())

    // Define routes
    app.Get("/", func(c fiber.Ctx) error {
        return c.SendString("Hello, Logger!")
    })

    log.Fatal(app.Listen(":3000"))
}

Cross-Origin Resource Sharing (CORS)

📖 CORS

package main

import (
    "log"

    "github.com/gofiber/fiber/v3"
    "github.com/gofiber/fiber/v3/middleware/cors"
)

func main() {
    app := fiber.New()

    // Use CORS middleware with default settings
    app.Use(cors.New())

    // Define routes
    app.Get("/", func(c fiber.Ctx) error {
        return c.SendString("CORS enabled!")
    })

    log.Fatal(app.Listen(":3000"))
}

Check CORS by passing any domain in Origin header:

curl -H "Origin: http://example.com" --verbose http://localhost:3000

Custom 404 Response

📖 HTTP Methods

package main

import (
    "log"

    "github.com/gofiber/fiber/v3"
)

func main() {
    app := fiber.New()

    // Define routes
    app.Get("/", static.New("./public"))

    app.Get("/demo", func(c fiber.Ctx) error {
        return c.SendString("This is a demo page!")
    })

    app.Post("/register", func(c fiber.Ctx) error {
        return c.SendString("Registration successful!")
    })

    // Middleware to handle 404 Not Found
    app.Use(func(c fiber.Ctx) error {
        return c.SendStatus(fiber.StatusNotFound) // => 404 "Not Found"
    })

    log.Fatal(app.Listen(":3000"))
}

JSON Response

📖 JSON

package main

import (
    "log"

    "github.com/gofiber/fiber/v3"
)

type User struct {
    Name string `json:"name"`
    Age  int    `json:"age"`
}

func main() {
    app := fiber.New()

    // Route that returns a JSON object
    app.Get("/user", func(c fiber.Ctx) error {
        return c.JSON(&User{"John", 20})
        // => {"na

fiber (gofiber/fiber)

Searching Database…

40.2K ·GitHub
Fiber
这是干什么的？Fiber 是一个受 Express 启发的 Go Web 框架，构建在 fasthttp 引擎之上，主打开发速度快、性能高。
它和直接用 Go 标准库的 net/http 有什么区别？它运行在 fasthttp 上，而不是标准的 net/http，并把后者包装成 Express 风格的 API——路由、中间件、模板引擎和 WebSocket 都包含在内，不用你自己去拼装这些组件。
怎么把它加到我的项目里？先创建项目目录，用 go mod init 初始化，然后运行 go get github.com/gofiber/fiber/v3。之后一个 Hello-World 服务器就是：调用 fiber.New()，写一条 app.Get 路由，再启动服务器——然后在浏览器里访问就行。
除了安装 Go，还需要别的东西吗？只需要 Go 本身，版本 1.26 或更高。README 里没有提到任何其他运行时、数据库或外部服务。
有什么需要留意的坑吗？fiber.Ctx 的值会在多个请求之间复用以实现零内存分配，所以只能在处理函数内部使用它，函数返回后绝不要保留对它的引用。另外 Fiber 用到了 unsafe，因此可能会落后于最新的 Go 版本；v3 是在 Go 1.26+ 上测试的。
它开箱即带哪些功能？包括健壮的路由、静态文件服务、支持 Next 的中间件、模板引擎、WebSocket、Socket.io、Server-Sent Events，还有限流器等等。
作者为什么要做 Fiber？为了欢迎从 Node.js 转过来的 gopher：Fiber 把 Express 的易用性和 Go 的原始性能结合在一起，遵循极简的 UNIX 哲学，让新手能快速上手开发。
我现有的 net/http 处理函数和中间件能在 Fiber 里用吗？可以。路由器能直接接收现有的 net/http 处理函数和原生的 fasthttp.RequestHandler 回调，adaptor 中间件还能在两个方向上转换整个应用和中间件链——你甚至可以把一个 Fiber 应用挂载到 net/http 服务器里。被适配的处理函数保持标准库的语义，拿不到 fiber.Ctx，而且有一定额外开销，所以原生的 Fiber 处理函数仍然最快。
它到底有多快？README 指向了 TechEmpower 基准测试，完整结果发布在项目的 Wiki 上，官方宣传的是极致性能加低内存占用，而不是给出某个具体数字。
What are similar projects?echo, chi, go-zero, iris, gofr, express, koa, sails
Which topics is it in?hacktoberfest2020, fast, middleware, express, web-framework, high-performance, microservices, websocket, http, golang, rest-api, hacktoberfest
Creator
gofiber
Size
44.8 MB
Stars
40.2K
Updated
CommitOct 16Releasev3.6.1Oct 14
Age
6y
Commits · 90 Days