@middy/s3-object-response/index.js

import { canPrefetch, createPrefetchClient, createClient } from '@middy/util';
import { S3Client, WriteGetObjectResponseCommand } from '@aws-sdk/client-s3';
const defaults = {
    AwsClient: S3Client,
    awsClientOptions: {},
    awsClientAssumeRole: undefined,
    awsClientCapture: undefined,
    disablePrefetch: false
};
const s3ObjectResponseMiddleware = (opts = {})=>{
    const options = {
        ...defaults,
        ...opts
    };
    let client;
    if (canPrefetch(options)) {
        client = createPrefetchClient(options);
    }
    const s3ObjectResponseMiddlewareBefore = async (request)=>{
        const { inputS3Url, outputRoute, outputToken } = request.event.getObjectContext;
        request.internal.s3ObjectResponse = {
            RequestRoute: outputRoute,
            RequestToken: outputToken
        };
        request.context.s3ObjectFetch = fetch(inputS3Url);
    };
    const s3ObjectResponseMiddlewareAfter = async (request)=>{
        if (!client) {
            client = await createClient(options, request);
        }
        if (request.response.body) {
            request.response.Body = request.response.body;
            delete request.response.body;
        }
        await client.send(new WriteGetObjectResponseCommand({
            ...request.internal.s3ObjectResponse,
            ...request.response
        }));
        return {
            statusCode: 200
        };
    };
    return {
        before: s3ObjectResponseMiddlewareBefore,
        after: s3ObjectResponseMiddlewareAfter
    };
};
export default s3ObjectResponseMiddleware;