Custom Context with Echo Framework

Extending Echo's context with custom functionality

Try the Custom Context

Implementation Code

// CustomContext wraps Echo's context with additional functionality
type CustomContext struct {
    echo.Context
}

// Success sends a JSON success response
func (c *CustomContext) Success(data interface{}) error {
    return c.JSON(http.StatusOK, map[string]interface{}{
        "success": true,
        "data":    data,
        "meta": map[string]interface{}{
            "timestamp": time.Now().UTC(),
            "requestId": c.Request().Header.Get("X-Request-ID"),
        },
    })
}

// Error sends a JSON error response
func (c *CustomContext) Error(status int, message string) error {
    return c.JSON(status, map[string]interface{}{
        "success": false,
        "error":   message,
        "meta": map[string]interface{}{
            "timestamp": time.Now().UTC(),
            "requestId": c.Request().Header.Get("X-Request-ID"),
        },
    })
}

// GetUserAgent returns the request's User-Agent header
func (c *CustomContext) GetUserAgent() string {
    return c.Request().UserAgent()
}

// CustomContextMiddleware creates a middleware that replaces the context
func CustomContextMiddleware(next echo.HandlerFunc) echo.HandlerFunc {
    return func(c echo.Context) error {
        cc := &CustomContext{c}
        return next(cc)
    }
}

package main

import (
    "net/http"
    "time"
    
    "github.com/labstack/echo/v4"
)

func main() {
    e := echo.New()
    
    // Register the custom context middleware
    e.Use(CustomContextMiddleware)
    
    // Standard Echo context route
    e.GET("/standard", func(c echo.Context) error {
        return c.String(http.StatusOK, "Standard Echo context response")
    })
    
    // Custom context route (will be wrapped by our middleware)
    e.GET("/custom", func(c echo.Context) error {
        // Type assertion to our CustomContext
        cc := c.(*CustomContext)
        
        // Use our custom methods
        if cc.GetUserAgent() == "" {
            return cc.Error(http.StatusBadRequest, "User-Agent header is required")
        }
        
        return cc.Success(map[string]interface{}{
            "message":    "Hello from Custom Context!",
            "userAgent":  cc.GetUserAgent(),
            "features":   []string{"Success()", "Error()", "GetUserAgent()"},
        })
    })
    
    e.Logger.Fatal(e.Start(":1323"))
}

Context Extension

Add your own methods to Echo's context for cleaner code.

Type Safety

Type assertions ensure you're working with your custom context.

Middleware Integration

Seamlessly integrate with Echo's middleware system.