Coco

An elegant, lightweight, and beautiful OpenAPI documentation renderer built for Go developers

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What is Coco?

English | 简体中文

Coco is an elegant, lightweight, and beautiful Go library that renders OpenAPI/Swagger specifications into stunning interactive API documentation. Zero dependencies, single-file bundle, perfectly embedded into Go binaries. Supports OpenAPI 2.0 and 3.0+ specifications with seamless integration into any Go web framework.

Advantages of Coco:

• Elegant DX - Minimal API design, integrate in just 30 seconds
• Beautiful UI - Built with Vue 3 + TailwindCSS, supports automatic light/dark theme switching
• Framework Agnostic - Works with all Go web frameworks (Gin, Echo, Fiber, Chi, net/http, etc.)
• Feature Complete - Built-in API testing, spec export, request history, internationalization, and more

Core Features

• Internationalization - Built-in English and Chinese support, extensible for more languages
• Zero Dependencies - Pure Go implementation, frontend assets fully embedded, no external tools required
• Framework Agnostic - Compatible with all Go web frameworks (Gin, Echo, Fiber, Chi, net/http, etc.)
• Flexible Configuration - Rich configuration options to meet various customization needs
• API Testing - Built-in interactive debug panel for instant API testing
• Spec Export - One-click export of OpenAPI/Swagger specification files
• Request History - Automatically saves debug history for easy review and reuse
• High Performance - Embedded static assets, single-file bundle, no additional HTTP requests

Installation

go get github.com/leehainuo/coco

Quick Start

Using Swag (Recommended)

Step 1: Install Swag

go install github.com/swaggo/swag/cmd/swag@latest

Step 2: Add annotations to your code

package main

import (
    "net/http"
    "github.com/leehainuo/coco"
)

// @title           My API
// @version         1.0
// @description     This is a sample API
// @host            localhost:8000
// @BasePath        /api

func main() {
    mux := http.NewServeMux()
    
    // Your API routes
    mux.HandleFunc("/api/hello", handleHello)
    
    // Mount Coco docs (Swag generates docs/swagger.json)
    mux.Handle("/docs/", coco.New("./docs/swagger.json"))
    
    http.ListenAndServe(":8000", mux)
}

// @Summary      Hello endpoint
// @Description  Returns a greeting message
// @Tags         example
// @Accept       json
// @Produce      json
// @Success      200  {string}  string  "Hello, World!"
// @Router       /hello [get]
func handleHello(w http.ResponseWriter, r *http.Request) {
    w.Write([]byte("Hello, World!"))
}

Step 3: Generate docs and run

# Generate OpenAPI documentation
swag init

# Run your application
go run main.go

Step 4: View your docs

Open your browser and visit http://localhost:8000/docs/ to see your beautiful API documentation!

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Other Usage Methods

Load from local file

handler := coco.New("./openapi.json")

Load from URL

handler := coco.New("", coco.SpecURL("https://example.com/openapi.json"))

Load from byte array

handler := coco.New("", coco.Spec(specBytes))

For more configuration and integration options, see Full Documentation

Integration Examples

net/http

package main

import (
    "net/http"
    "github.com/leehainuo/coco"
)

func main() {
    mux := http.NewServeMux()
    
    // Your API routes
    mux.HandleFunc("/api/users", handleUsers)
    
    // Mount documentation
    mux.Handle("/docs/", coco.New("./openapi.json",
        coco.Title("User API"),
    ))
    
    http.ListenAndServe(":8000", mux)
}

Gin

package main

import (
    "github.com/gin-gonic/gin"
    "github.com/leehainuo/coco"
)

func main() {
    r := gin.Default()
    
    // Your API routes
    r.GET("/api/users", getUsers)
    
    // Mount documentation
    r.Any("/docs/*any", gin.WrapH(coco.New("./openapi.json",
        coco.Title("User API"),
    )))
    
    r.Run(":8000")
}

Echo

package main

import (
    "github.com/labstack/echo/v4"
    "github.com/leehainuo/coco"
)

func main() {
    e := echo.New()
    
    // Your API routes
    e.GET("/api/users", getUsers)
    
    // Mount documentation
    e.Any("/docs/*", echo.WrapHandler(coco.New("./openapi.json",
        coco.Title("User API"),
    )))
    
    e.Start(":8000")
}

Fiber

package main

import (
    "net/http"
    "github.com/gofiber/fiber/v3"
    "github.com/gofiber/fiber/v3/middleware/adaptor"
    "github.com/leehainuo/coco"
)

func main() {
    app := fiber.New()
    
    // Your API routes
    app.Get("/api/users", getUsers)
    
    // Mount documentation
    handler := coco.New("./openapi.json",
        coco.Title("User API"),
    )
    app.All("/docs/*", adaptor.HTTPHandler(http.HandlerFunc(handler.ServeHTTP)))
    
    app.Listen(":8000")
}

Chi

package main

import (
    "net/http"
    "github.com/go-chi/chi/v5"
    "github.com/leehainuo/coco"
)

func main() {
    r := chi.NewRouter()
    
    // Your API routes
    r.Get("/api/users", getUsers)
    
    // Mount documentation
    r.HandleFunc("/docs/*", func(w http.ResponseWriter, req *http.Request) {
        handler := coco.New("./openapi.json",
            coco.Title("User API"),
        )
        handler.ServeHTTP(w, req)
    })
    
    http.ListenAndServe(":8000", r)
}

Configuration Options

Spec Sources

// Load from file path
coco.New("./openapi.json")

// Load from byte array
coco.New("", coco.Spec(specBytes))

// Load from remote URL
coco.New("", coco.SpecURL("https://example.com/openapi.json"))

UI Configuration

// Set document title
coco.Title("My API Documentation")

// Set theme: "light", "dark", "auto"
coco.Theme("dark")

// Set language: "en", "zh", "custom"
coco.Lang("en")

// Add a custom language from a translation file (optional)
coco.I18n("./i18n.fr.json")

Feature Toggles

// Enable/disable debug panel (enabled by default)
coco.EnableDebug(true)

// Enable/disable export feature (enabled by default)
coco.EnableExport(true)

// Enable/disable history (enabled by default)
coco.EnableHistory(true)

OpenAPI Generation Tools Integration

Using Huma v2

package main

import (
    "context"
    "net/http"
    
    "github.com/danielgtaylor/huma/v2"
    "github.com/danielgtaylor/huma/v2/adapters/humago"
    "github.com/leehainuo/coco"
)

func main() {
    mux := http.NewServeMux()
    api := humago.New(mux, huma.DefaultConfig("My API", "1.0.0"))
    
    // Register your API
    huma.Register(api, huma.Operation{
        OperationID: "get-users",
        Method:      http.MethodGet,
        Path:        "/api/users",
        Summary:     "Get users",
    }, func(ctx context.Context, input *struct{}) (*struct{}, error) {
        return &struct{}{}, nil
    })
    
    // Get OpenAPI spec and mount documentation
    spec, _ := api.OpenAPI().MarshalJSON()
    mux.Handle("/docs/", coco.New("",
        coco.Spec(spec),
        coco.Title("My API - Huma"),
    ))
    
    http.ListenAndServe(":8000", mux)
}

Using Swag

package main

import (
    "net/http"
    "github.com/leehainuo/coco"
)

// @title My API
// @version 1.0
// @description This is my API
// @host localhost:8000
// @BasePath /api

func main() {
    mux := http.NewServeMux()
    
    // Your API routes
    mux.HandleFunc("/api/users", getUsers)
    
    // Mount documentation (swag generates docs/swagger.json)
    mux.Handle("/docs/", coco.New("./docs/swagger.json",
        coco.Title("My API - Swag"),
    ))
    
    http.ListenAndServe(":8000", mux)
}

Generate documentation before running:

swag init

Themes and Languages

Theme Options

• light - Light theme
• dark - Dark theme
• auto - Follow system (default)

Language Options

• en - English (default)
• zh - Chinese
• custom - A custom language loaded from your own i18n.json

Users can switch themes and languages anytime in the top-right corner of the interface.

To add a language beyond the built-in English and Chinese, provide a translation file via coco.I18n (file), coco.I18nData (bytes) or coco.I18nURL (URL), then select it with coco.Lang("custom"). See the Configuration Guide for details.

Documentation

• English Docs: docs/en/ - Complete English documentation
• 中文文档: docs/zh/ - 完整的中文使用指南
• Documentation Home: docs/ - Choose your language / 选择你的语言

Complete Examples

Check the example/framework directory for complete examples:

• net/http - Standard library examples
• Gin - Gin framework integration
• Echo - Echo framework integration
• Fiber - Fiber v3 framework integration
• Chi - Chi router integration

Each framework provides examples for both Huma and Swag OpenAPI generation methods.

📚 Documentation

• English: docs/en/
• 中文: docs/zh/

🤝 Contributing

Contributions, issues, and suggestions are welcome!

If you're using Coco or find it helpful, please give us a Star ⭐

License

MIT License - See LICENSE file for details

Give a Star! ⭐

If you like this project or are using it to learn or build your solution, please give it a Star to get updates on new releases. Your support matters!

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Made with ❤️ by leehainuo