Copying files to S3rver for serverless-offline testing using serverless-s3-local

CopyFiles.js

'use strict';
// Matt Warner, July 2018
// Use at your own risk, no warranties, no guarantees, etc.
// Code to copy local files into the format used by serverless-s3-local (which uses S3rver)

const {promisify} = require('util');

const fs = require('fs');
const readFileAsync = promisify(fs.readFile);
const readDirAsync = promisify(fs.readdir);
const AWS = require('aws-sdk');
const s3 = new AWS.S3({
    s3ForcePathStyle: true,
    endpoint: new AWS.Endpoint('http://localhost:8000'),
});

/**
 * Copy files recursively to the serverless-s3-local emulated bucket
 * We use the S3 calls because the emulated bucket stores files as directories with three dot files
 * to emulate S3 behavior.
 * So a file named index.html will end up like this:
 * index.html/
 * With three dot files named .dummys3_content, .dummys3_metadata, .dummys3_content.md5
 * If I'm copying a lot of files, doing this by hand is painful, so the code below does it for me.
 * @param prefix
 * @param dirName
 * @returns {Promise<void>}
 */
const main = async (prefix, dirName) => {
    if (!dirName) dirName = prefix;
    let listing = await readDirAsync(dirName);
    console.log(listing);
    let fileList = listing.map(entry => !entry.match(/^\./) && fs.statSync(dirName + "/" + entry).isFile() ? dirName + "/" + entry : null); // get only filenames
    fileList = fileList.filter(item => item); // remove nulls
    let dirList = listing.map(entry => !entry.match(/^\./) && !fs.statSync(dirName + "/" + entry).isFile() ? dirName + "/" + entry : null); // get only directories
    dirList = dirList.filter(item => item); // remove nulls
    console.log("files", fileList);
    console.log("Directories", dirList);
    let filesPromise = Promise.all(fileList.map(async item => {
        let content = await readFileAsync(item);
        let extension = item.replace(/^.*\.(.*)/, '$1').toLowerCase();
        let contentType;
        switch (extension) {
            case "htm":
            case "html": {
                contentType = "text/html";
                break;
            }
            case "jpg":
            case "jpeg":
            case "png":
            case "gif": {
                contentType = "image/" + extension.replace(/jpg/, 'jpeg');
                break;
            }
            case "pdf": {
                contentType = "application/pdf";
                break;
            }
            case "css": {
                contentType = "text/css";
                break;
            }
            case "js": {
                contentType = "application/javascript";
                break;
            }
            default : {
                contentType = "application/octet-stream";
            }
        }
        let params = {
            Bucket: 'YOUR_LOCAL_BUCKET_NAME',
            Key: item.replace(prefix + "/", ''),
            Body: content,
            ContentType: contentType + ";charset=utf-8"
        };
        // console.log("params", params);
        await s3.putObject(params).promise();
    }));

    let dirsPromise = Promise.all(dirList.map(async item => await main(prefix, item)));

    await Promise.all([filesPromise, dirsPromise]);
};

main("/path/to/directory/with/files/to/copy");