Zuplo

API Key Authentication

Secure Your Gin API with API Keys

The Zuplo API Gateway protects your backend API from unauthorized access, abuse, and overload. Add API key authentication to your Gin API in minutes.

Secure Access

Authenticate every request before it reaches your backend.

Control Costs

Set rate limits and quotas to prevent runaway usage.

Ensure Reliability

Shield your backend from overload with traffic management.

How it works

The Zuplo API Gateway sits between your clients and your Gin backend, providing a secure layer of protection and control.

Client
Zuplo API Gateway

Customer VPC

Backend

Step-by-step tutorial

It takes only a few minutes to put Zuplo in front of your Gin backend, adding API key authentication, and configuring your origin to trust requests from Zuplo using shared secrets.

1

Create a Route in Zuplo

First, create a new route in your Zuplo project that will proxy requests to your Gin backend. This route will be the entry point for your API consumers.

Creating a route in Zuplo
Learn how to create routes

📄 OpenAPI native. Import your existing OpenAPI spec to instantly create routes and power your API documentation .

2

Add API Key Authentication Policy

Add the API Key Authentication policy to your route. This policy validates incoming API keys and ensures only authorized consumers can access your API.

Adding API Key Authentication policy in Zuplo
API Key Authentication docs

🔐 Leaked key? No problem. As a GitHub Secret Scanning partner, Zuplo can automatically revoke exposed keys before they can be exploited.

3

Add Set Header Policy

Add the Set Header policy to your route. This policy sets the shared secret header on requests to ensure only requests from Zuplo are accepted by your API.

Adding Set Header policy in Zuplo
Set Header Policy docs
4

Secure Your Gin API with the Shared Secret

Configure your Gin backend to validate the shared secret header set by Zuplo. This ensures that only requests coming through your Zuplo gateway are accepted.

GoGo
package main

import (
	"crypto/subtle"
	"fmt"
	"net/http"
	"os"

	"github.com/gin-gonic/gin"
)

// validateSharedSecret middleware to validate shared secret header
func validateSharedSecret() gin.HandlerFunc {
	return func(c *gin.Context) {
		secret := c.GetHeader("X-Shared-Secret")
		expectedSecret := os.Getenv("SHARED_SECRET")

		if expectedSecret == "" {
			c.JSON(http.StatusInternalServerError, gin.H{"error": "Server configuration error"})
			c.Abort()
			return
		}

		if secret == "" {
			c.JSON(http.StatusUnauthorized, gin.H{"error": "No secret provided"})
			c.Abort()
			return
		}

		// Use timing-safe comparison to prevent timing attacks
		if subtle.ConstantTimeCompare([]byte(secret), []byte(expectedSecret)) != 1 {
			c.JSON(http.StatusUnauthorized, gin.H{"error": "Invalid secret"})
			c.Abort()
			return
		}

		c.Next()
	}
}

func main() {
	r := gin.Default()

	r.GET("/protected", validateSharedSecret(), func(c *gin.Context) {
		c.JSON(http.StatusOK, gin.H{"message": "Access granted"})
	})

	if err := r.Run(":8080"); err != nil {
		fmt.Printf("Server failed to start: %v\n", err)
	}
}
5

Call Your API Through Zuplo

Now you can call your API through Zuplo using an API key. The request will be authenticated at the gateway, and securely forwarded to your Gin backend.

Terminalbash
curl -X GET \
  'https://your-api.zuplo.dev/your-route' \
  -H 'Authorization: Bearer YOUR_API_KEY'

Ready to secure your API?

Get started with Zuplo for free and add API key authentication to your Gin API in minutes.

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