a very basic lambda proxy for local development, accepts -local flag to run the echo based proxy

lambda.go

package main

import (
	"bytes"
	"flag"
	"fmt"

	"github.com/aws/aws-lambda-go/events"
	"github.com/aws/aws-lambda-go/lambda"
	"github.com/labstack/echo"
)
var isLocal = flag.Bool("local", false, "is running the local runtime stack")

func HandleRequest(req events.APIGatewayProxyRequest) (events.APIGatewayProxyResponse, error) {
	return events.APIGatewayProxyResponse{
		StatusCode: http.StatusOk,
		Body:       req.body,
	}
}

func lambdaProxy(c echo.Context) error {
	buf := new(bytes.Buffer)
	buf.ReadFrom(c.Request().Body)
	bodyStr := buf.String()

	var headerMap = map[string]string{}
	header := c.Request().Header
	for name, values := range header {
		for _, value := range values {
			headerMap[name] = value
		}
	}
	var queryMap = map[string]string{}
	query := c.Request().URL.Query()
	for name, values := range query {
		for _, value := range values {
			queryMap[name] = value
		}
	}
	req := events.APIGatewayProxyRequest{
		Path:                  c.Request().URL.Path, 
		HTTPMethod:            c.Request().Method,   
		Headers:               headerMap,
		QueryStringParameters: queryMap, 
		//PathParameters: c.Request().URL. NOT SUPPORTED
		// StageVariables: NOT SUPPORTED
		// RequestContext: NOT SUPPORTED
		Body:            bodyStr, 
		IsBase64Encoded: false, 
	}
	resp, _ := HandleRequest(req)
	return c.String(resp.StatusCode, resp.Body)
}
func main() {
	flag.Parse()
	if *isLocal {
		fmt.Println("is local")
		e := echo.New()
		e.Any("/*", lambdaProxy)
		e.Logger.Fatal(e.Start(":1323"))
		return
	}

	lambda.Start(HandleRequest)
}