Go Integration Guide

Overview

This guide covers everything you need to protect your Go API with Unkey, including middleware for the standard library, Gin framework, and Echo framework. What you’ll learn:

Quick setup with the Unkey Go SDK
Middleware for net/http (standard library)
Gin framework integration
Echo framework integration
Permission-based access control
Production-ready patterns

Prerequisites

Go 1.21 or higher
Unkey account (free)
API created in your Unkey dashboard

Quick Start

Install the SDK

go get github.com/unkeyed/sdks/api/go/v2@latest

Set up credentials

Get a root key from Settings → Root Keys and set it as an environment variable:

export UNKEY_ROOT_KEY="unkey_..."

Create middleware

Here’s how to verify API keys with standard library net/http:

main.go

package main

import (
    "context"
    "net/http"
    "os"
    "strings"

    unkey "github.com/unkeyed/sdks/api/go/v2"
    "github.com/unkeyed/sdks/api/go/v2/models/components"
)

var unkeyClient *unkey.Unkey

func init() {
    unkeyClient = unkey.New(
        unkey.WithSecurity(os.Getenv("UNKEY_ROOT_KEY")),
    )
}

// AuthMiddleware verifies API keys on incoming requests
func AuthMiddleware(next http.Handler) http.Handler {
    return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
        // Extract API key from header
        authHeader := r.Header.Get("Authorization")
        if authHeader == "" {
            http.Error(w, `{"error": "Missing Authorization header"}`, http.StatusUnauthorized)
            return
        }

        apiKey := strings.TrimPrefix(authHeader, "Bearer ")

        // Verify with Unkey
        res, err := unkeyClient.Keys.VerifyKey(r.Context(), components.V2KeysVerifyKeyRequestBody{
            Key: apiKey,
        })

        if err != nil {
            http.Error(w, `{"error": "Verification service unavailable"}`, http.StatusServiceUnavailable)
            return
        }

        result := res.V2KeysVerifyKeyResponseBody.Data

        if !result.Valid {
            http.Error(w, `{"error": "Invalid API key"}`, http.StatusUnauthorized)
            return
        }

        // Add key info to context for handlers
        ctx := context.WithValue(r.Context(), "keyId", *result.KeyID)
        next.ServeHTTP(w, r.WithContext(ctx))
    })
}

func main() {
    mux := http.NewServeMux()
    
    // Protected route
    mux.HandleFunc("/api/protected", func(w http.ResponseWriter, r *http.Request) {
        w.Header().Set("Content-Type", "application/json")
        w.Write([]byte(`{"message": "Access granted!"}`))
    })

    // Wrap with auth middleware
    http.ListenAndServe(":8080", AuthMiddleware(mux))
}

Run and test

go run main.go

Test it with a valid API key:

curl -H "Authorization: Bearer YOUR_API_KEY" http://localhost:8080/api/protected

Standard Library (net/http)

Production-Ready Middleware

Here’s a complete middleware implementation with context, options, and error handling:

middleware/auth.go

package middleware

import (
    "context"
    "encoding/json"
    "net/http"
    "os"
    "slices"
    "strings"
    "time"

    unkey "github.com/unkeyed/sdks/api/go/v2"
    "github.com/unkeyed/sdks/api/go/v2/models/components"
)

// KeyContext stores Unkey verification result in request context
type KeyContext struct {
    KeyID       string
    OwnerID     string
    Meta        map[string]any
    Permissions []string
    Roles       []string
}

type contextKey string

const unkeyContextKey contextKey = "unkey"

var unkeyClient *unkey.Unkey

func init() {
    unkeyClient = unkey.New(
        unkey.WithSecurity(os.Getenv("UNKEY_ROOT_KEY")),
    )
}

// AuthMiddleware creates a middleware that verifies API keys
func AuthMiddleware(opts ...AuthOption) func(http.Handler) http.Handler {
    options := &authOptions{
        headerName: "Authorization",
        prefix:     "Bearer ",
        required:   true,
    }
    
    for _, opt := range opts {
        opt(options)
    }

    return func(next http.Handler) http.Handler {
        return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
            w.Header().Set("Content-Type", "application/json")

            authHeader := r.Header.Get(options.headerName)
            if authHeader == "" {
                if options.required {
                    w.WriteHeader(http.StatusUnauthorized)
                    json.NewEncoder(w).Encode(map[string]string{
                        "error": "Missing API key",
                        "code":  "MISSING_KEY",
                    })
                    return
                }
                next.ServeHTTP(w, r)
                return
            }

            apiKey := strings.TrimPrefix(authHeader, options.prefix)

            ctx, cancel := context.WithTimeout(r.Context(), 5*time.Second)
            defer cancel()

            res, err := unkeyClient.Keys.VerifyKey(ctx, components.V2KeysVerifyKeyRequestBody{
                Key: apiKey,
            })

            if err != nil {
                w.WriteHeader(http.StatusServiceUnavailable)
                json.NewEncoder(w).Encode(map[string]string{
                    "error":   "Verification service unavailable",
                    "code":    "SERVICE_ERROR",
                    "message": err.Error(),
                })
                return
            }

            result := res.V2KeysVerifyKeyResponseBody.Data

            if !result.Valid {
                code := string(result.Code)
                w.WriteHeader(http.StatusUnauthorized)
                json.NewEncoder(w).Encode(map[string]any{
                    "error": "Invalid API key",
                    "code":  code,
                })
                return
            }

            // Build context
            keyCtx := &KeyContext{
                KeyID:       *result.KeyID,
                Meta:        result.Meta,
                Permissions: result.Permissions,
                Roles:       result.Roles,
            }

            if result.Identity != nil {
                keyCtx.OwnerID = result.Identity.ExternalID
            }

            ctx = context.WithValue(r.Context(), unkeyContextKey, keyCtx)
            next.ServeHTTP(w, r.WithContext(ctx))
        })
    }
}

// AuthOption configures the auth middleware
type authOptions struct {
    headerName string
    prefix     string
    required   bool
}

type AuthOption func(*authOptions)

func WithHeaderName(name string) AuthOption {
    return func(o *authOptions) {
        o.headerName = name
    }
}

func WithPrefix(prefix string) AuthOption {
    return func(o *authOptions) {
        o.prefix = prefix
    }
}

func WithOptional() AuthOption {
    return func(o *authOptions) {
        o.required = false
    }
}

// GetKeyContext retrieves the Unkey context from request
func GetKeyContext(r *http.Request) (*KeyContext, bool) {
    ctx, ok := r.Context().Value(unkeyContextKey).(*KeyContext)
    return ctx, ok
}

// RequirePermission middleware checks if the key has a specific permission
func RequirePermission(permission string) func(http.Handler) http.Handler {
    return func(next http.Handler) http.Handler {
        return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
            keyCtx, ok := GetKeyContext(r)
            if !ok {
                w.WriteHeader(http.StatusUnauthorized)
                json.NewEncoder(w).Encode(map[string]string{
                    "error": "Authentication required",
                    "code":  "AUTH_REQUIRED",
                })
                return
            }

            if slices.Contains(keyCtx.Permissions, permission) {
                next.ServeHTTP(w, r)
                return
            }

            w.WriteHeader(http.StatusForbidden)
            json.NewEncoder(w).Encode(map[string]string{
                "error": "Insufficient permissions",
                "code":  "FORBIDDEN",
                "required": permission,
            })
        })
    }
}

Usage:

main.go

package main

import (
    "encoding/json"
    "net/http"
    "time"
    
    "yourapp/middleware"
)

func main() {
    mux := http.NewServeMux()

    // Public route
    mux.HandleFunc("/health", func(w http.ResponseWriter, r *http.Request) {
        json.NewEncoder(w).Encode(map[string]string{"status": "ok"})
    })

    // Protected routes
    mux.Handle("/api/protected", middleware.AuthMiddleware()(http.HandlerFunc(protectedHandler)))

    // Protected with permission check
    mux.Handle("/api/admin", middleware.AuthMiddleware()(middleware.RequirePermission("admin:read")(http.HandlerFunc(adminHandler))))

    server := &http.Server{
        Addr:         ":8080",
        Handler:      mux,
        ReadTimeout:  15 * time.Second,
        WriteTimeout: 15 * time.Second,
    }

    server.ListenAndServe()
}

func protectedHandler(w http.ResponseWriter, r *http.Request) {
    keyCtx, _ := middleware.GetKeyContext(r)
    json.NewEncoder(w).Encode(map[string]any{
        "message": "Access granted",
        "key_id":  keyCtx.KeyID,
    })
}

func adminHandler(w http.ResponseWriter, r *http.Request) {
    json.NewEncoder(w).Encode(map[string]string{
        "message": "Admin access granted",
    })
}

Gin Framework

For the Gin web framework:

go get github.com/gin-gonic/gin

main.go

package main

import (
    "net/http"
    "os"
    "slices"
    "strings"

    "github.com/gin-gonic/gin"
    unkey "github.com/unkeyed/sdks/api/go/v2"
    "github.com/unkeyed/sdks/api/go/v2/models/components"
)

var unkeyClient *unkey.Unkey

func init() {
    unkeyClient = unkey.New(
        unkey.WithSecurity(os.Getenv("UNKEY_ROOT_KEY")),
    )
}

func UnkeyAuth() gin.HandlerFunc {
    return func(c *gin.Context) {
        authHeader := c.GetHeader("Authorization")
        if authHeader == "" {
            c.AbortWithStatusJSON(http.StatusUnauthorized, gin.H{
                "error": "Missing Authorization header",
                "code":  "MISSING_KEY",
            })
            return
        }

        apiKey := strings.TrimPrefix(authHeader, "Bearer ")

        res, err := unkeyClient.Keys.VerifyKey(c.Request.Context(), components.V2KeysVerifyKeyRequestBody{
            Key: apiKey,
        })

        if err != nil {
            c.AbortWithStatusJSON(http.StatusServiceUnavailable, gin.H{
                "error":   "Verification service unavailable",
                "code":    "SERVICE_ERROR",
                "message": err.Error(),
            })
            return
        }

        if !res.V2KeysVerifyKeyResponseBody.Data.Valid {
            code := string(res.V2KeysVerifyKeyResponseBody.Data.Code)
            c.AbortWithStatusJSON(http.StatusUnauthorized, gin.H{
                "error": "Invalid API key",
                "code":  code,
            })
            return
        }

        // Store verification result in context
        c.Set("unkey", &res.V2KeysVerifyKeyResponseBody.Data)
        c.Next()
    }
}

func RequirePermission(permission string) gin.HandlerFunc {
    return func(c *gin.Context) {
        result, exists := c.Get("unkey")
        if !exists {
            c.AbortWithStatusJSON(http.StatusUnauthorized, gin.H{
                "error": "Authentication required",
            })
            return
        }

        keyResult, ok := result.(*components.V2KeysVerifyKeyResponseData)
        if !ok || keyResult == nil {
            c.AbortWithStatusJSON(http.StatusInternalServerError, gin.H{
                "error": "Invalid authentication context",
            })
            return
        }

        if !slices.Contains(keyResult.Permissions, permission) {
            c.AbortWithStatusJSON(http.StatusForbidden, gin.H{
                "error":    "Insufficient permissions",
                "required": permission,
            })
            return
        }
        c.Next()
    }
}

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

    // Public routes
    r.GET("/health", func(c *gin.Context) {
        c.JSON(http.StatusOK, gin.H{"status": "ok"})
    })

    // Protected API group
    api := r.Group("/api")
    api.Use(UnkeyAuth())
    {
        api.GET("/data", func(c *gin.Context) {
            result, _ := c.Get("unkey")
            keyResult := result.(*components.V2KeysVerifyKeyResponseData)
            
            c.JSON(http.StatusOK, gin.H{
                "message": "Access granted",
                "key_id":  *keyResult.KeyID,
            })
        })
    }

    // Admin routes with permission check
    admin := r.Group("/api/admin")
    admin.Use(UnkeyAuth(), RequirePermission("admin:read"))
    {
        admin.GET("/users", func(c *gin.Context) {
            c.JSON(http.StatusOK, gin.H{
                "message": "Admin access granted",
                "users":   []string{"user1", "user2"},
            })
        })
    }

    r.Run(":8080")
}

Echo Framework

For the Echo web framework:

go get github.com/labstack/echo/v4

main.go

package main

import (
    "net/http"
    "os"
    "slices"
    "strings"

    "github.com/labstack/echo/v4"
    "github.com/labstack/echo/v4/middleware"
    unkey "github.com/unkeyed/sdks/api/go/v2"
    "github.com/unkeyed/sdks/api/go/v2/models/components"
)

var unkeyClient *unkey.Unkey

func init() {
    unkeyClient = unkey.New(
        unkey.WithSecurity(os.Getenv("UNKEY_ROOT_KEY")),
    )
}

func UnkeyAuthMiddleware() echo.MiddlewareFunc {
    return func(next echo.HandlerFunc) echo.HandlerFunc {
        return func(c echo.Context) error {
            authHeader := c.Request().Header.Get("Authorization")
            if authHeader == "" {
                return c.JSON(http.StatusUnauthorized, map[string]string{
                    "error": "Missing Authorization header",
                })
            }

            apiKey := strings.TrimPrefix(authHeader, "Bearer ")

            res, err := unkeyClient.Keys.VerifyKey(c.Request().Context(), components.V2KeysVerifyKeyRequestBody{
                Key: apiKey,
            })

            if err != nil {
                return c.JSON(http.StatusServiceUnavailable, map[string]string{
                    "error": "Verification service unavailable",
                })
            }

            if !res.V2KeysVerifyKeyResponseBody.Data.Valid {
                return c.JSON(http.StatusUnauthorized, map[string]string{
                    "error": "Invalid API key",
                })
            }

            c.Set("unkey", &res.V2KeysVerifyKeyResponseBody.Data)
            return next(c)
        }
    }
}

func RequirePermission(permission string) echo.MiddlewareFunc {
    return func(next echo.HandlerFunc) echo.HandlerFunc {
        return func(c echo.Context) error {
            result := c.Get("unkey")
            if result == nil {
                return c.JSON(http.StatusUnauthorized, map[string]string{
                    "error": "Authentication required",
                })
            }

            keyResult, ok := result.(*components.V2KeysVerifyKeyResponseData)
            if !ok || keyResult == nil {
                return c.JSON(http.StatusInternalServerError, map[string]string{
                    "error": "Invalid authentication context",
                })
            }

            if !slices.Contains(keyResult.Permissions, permission) {
                return c.JSON(http.StatusForbidden, map[string]string{
                    "error":    "Insufficient permissions",
                    "required": permission,
                })
            }
            return next(c)
        }
    }
}

func main() {
    e := echo.New()
    
    e.Use(middleware.Logger())
    e.Use(middleware.Recover())

    // Public routes
    e.GET("/health", func(c echo.Context) error {
        return c.JSON(http.StatusOK, map[string]string{"status": "ok"})
    })

    // Protected routes
    api := e.Group("/api")
    api.Use(UnkeyAuthMiddleware())
    {
        api.GET("/data", func(c echo.Context) error {
            result := c.Get("unkey").(*components.V2KeysVerifyKeyResponseData)
            return c.JSON(http.StatusOK, map[string]any{
                "message": "Access granted",
                "key_id":  *result.KeyID,
            })
        })
    }

    // Admin routes
    admin := e.Group("/api/admin")
    admin.Use(UnkeyAuthMiddleware(), RequirePermission("admin:read"))
    {
        admin.GET("/users", func(c echo.Context) error {
            return c.JSON(http.StatusOK, map[string]any{
                "message": "Admin access granted",
                "users":   []string{"user1", "user2"},
            })
        })
    }

    e.Start(":8080")
}

Next Steps

Add rate limiting

Protect your endpoints from abuse

Go SDK Reference

Complete Go SDK documentation

Authorization

Add roles and permissions

Cookbook

More Go recipes and examples

Get Started

Core Features

Integration Guides

Advanced Topics

Security

Platform

Go Integration Guide

Overview

Prerequisites

Quick Start

Standard Library (net/http)

Production-Ready Middleware

Gin Framework

Echo Framework

Next Steps

Add rate limiting

Go SDK Reference

Authorization

Cookbook

Build docs developers (and LLMs) love

Get Started

Core Features

Integration Guides

Advanced Topics

Security

Platform

Documentation Index

​Overview

​Prerequisites

​Quick Start

​Standard Library (net/http)

​Production-Ready Middleware

​Gin Framework

​Echo Framework

​Next Steps

Add rate limiting

Go SDK Reference

Authorization

Cookbook

Build docs developers (and LLMs) love

Overview

Prerequisites

Quick Start

Standard Library (net/http)

Production-Ready Middleware

Gin Framework

Echo Framework

Next Steps