为什么 AWS lambda function 在从 .netlify 开发服务器执行时不返回 jpg/png 图像？

Question

I am creating a serverless function that accepts a URL as a query string and returns the image located at that URL.

package main

import (
    "context"
    "encoding/base64"
    "fmt"
    "io/ioutil"
    "net/http"

    "github.com/aws/aws-lambda-go/events"
    "github.com/aws/aws-lambda-go/lambda"
)

func handler(ctx context.Context, request events.APIGatewayProxyRequest) (*events.APIGatewayProxyResponse, error) {

    // Store query parameters in a variable
    url := request.QueryStringParameters["url"]

    // download image as save it as imageBytes
    response, err := http.Get(url)
    if err != nil {
        return nil, fmt.Errorf("Could not connect to the provided url.")
    }
    defer response.Body.Close()

    imageBytes, err := ioutil.ReadAll(response.Body)
    if err != nil {
        return nil, fmt.Errorf("Error occured.")
    }

    // convert to base64 string
    imageBase64 := base64.StdEncoding.EncodeToString(imageBytes)

    // send back response
    return &events.APIGatewayProxyResponse{
        StatusCode: http.StatusOK,
        Headers: map[string]string{
            "Content-Type":                 "image/png",
            "Access-Control-Allow-Origin":  "*",
            "Access-Control-Allow-Headers": "Content-Type",
        },
        Body:            imageBase64,
        IsBase64Encoded: true,
    }, nil
}

func main() {
    lambda.Start(handler)
}

Additionally, I attempted to send the image bytes as a normal string without encoding it with base64, but that did not work either. Instead, all I am seeing is a white rectangular box. I'm using netlify dev command to execute this function.

What am I missing?

Answer 1

This is a known bug on netlify and it works AWS-Lambda.