lambdahttp

lambdahttp

Run standard Go HTTP handlers in AWS Lambda with automatic integration for API Gateway, ALB, and EventBridge.

Overview

This package allows you to run any standard Go http.Handler in AWS Lambda without modification. It automatically detects and handles requests from:

• API Gateway (v1 and v2)
• Application Load Balancer (ALB)
• EventBridge
• Lambda Function URLs

The main benefits are:

• Low-Cost Migration: Write your HTTP handlers using standard Go patterns and libraries, then deploy them to AWS Lambda without changing your code
• Cloud Flexibility: Easily switch between running your application on traditional servers and AWS Lambda without code changes
• Future-Proof: If you decide to move away from Lambda in the future, your code remains standard and portable

Features

• 🔄 Use standard http.Handler interface
• 🔍 Automatic detection of AWS integration type
• 🌐 Support for multiple AWS services:
  • API Gateway v1
  • API Gateway v2
  • Application Load Balancer
  • EventBridge
  • Lambda Function URLs
• 📝 Preserves HTTP headers, query parameters, and body

Installation

go get github.com/tjamet/lambdahttp

Quick Start

Here's a simple example of how to use the package:

package main

import (
    "net/http"
    "github.com/tjamet/lambdahttp"
)

func main() {
    // Create your HTTP handler as usual
    mux := http.NewServeMux()
    mux.HandleFunc("/", func(w http.ResponseWriter, r *http.Request) {
        w.Header().Set("Content-Type", "application/json")
        w.Write([]byte(`{"message": "Hello from Lambda!"}`))
    })

    // Start the Lambda handler
    serverless.StartLambdaHandler(mux)
}

Advanced Usage

Custom Handler

If you need more control over the Lambda function, you can use NewAWSLambdaHTTPHandler:

package main

import (
    "context"
    "net/http"
    "github.com/tjamet/lambdahttp"
)

func main() {
    handler := serverless.NewAWSLambdaHTTPHandler(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
        // Access the original Lambda request if needed
        originalRequest := serverless.GetOriginalRequest(r)
        
        // Get the integration type
        integrationType := serverless.GetIntegrationType(r)
        
        // Your handler logic here
        w.Header().Set("Content-Type", "application/json")
        w.Write([]byte(`{"message": "Hello!"}`))
    }))

    lambda.Start(handler)
}

Integration Types

The package automatically detects the following integration types:

• IntegrationTypeAPIGWv1: API Gateway REST API (v1)
• IntegrationTypeAPIGWv2: API Gateway HTTP API (v2), EventBridge, and Lambda Function URLs
• IntegrationTypeALB: Application Load Balancer

AWS Service Configuration

API Gateway

For API Gateway, you can use either REST API (v1) or HTTP API (v2). The package will automatically detect the version and handle the request appropriately.

Application Load Balancer

When using an ALB trigger, make sure your target group protocol is set to HTTP.

EventBridge

The package handles EventBridge events by converting them to HTTP requests. The request will be sent as a POST request to the handler.

Lambda Function URLs

Function URLs are automatically detected and handled as API Gateway v2 requests.

Infrastructure as Code Example

For a complete example of how to wire all these integrations together, check out our Terraform module example. This module helps:

• Setting up Lambda functions with this package
• Configuring API Gateway integrations (v1 and v2)
• Setting up ALB targets
• Configuring EventBridge rules
• Managing Lambda Function URLs
• Handling permissions and IAM roles

Contributing

Contributions are welcome! Please feel free to submit an Issue or a Pull Request.

License

[Apache - 2.0] - See LICENSE file for details.