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Typescript not bundling modules

I have a node application that compiles typescript files to a dist folder and then serves these files as lambda resolvers via aws cdk. Here is an example of my setup:
The code
register.ts
import ValidateUserFields from '../utils/forms';
exports.main = async function (event: any, context: any) {
return {
statusCode: 200,
};
}
register-lambda-config.ts
import { Construct } from 'constructs';
import * as apigateway from 'aws-cdk-lib/aws-apigateway';
import * as lambda from 'aws-cdk-lib/aws-lambda';
import * as s3 from 'aws-cdk-lib/aws-s3';
export class FrontendService extends Construct {
constructor(scope: Construct, id: string) {
super(scope, id);
const api = new apigateway.RestApi(this, 'frontend-api', {
restApiName: 'Frontend Service',
description: 'This service serves the frontend.',
});
const functionName = 'register';
const handler = new lambda.Function(this, functionName, {
functionName,
runtime: lambda.Runtime.NODEJS_14_X,
code: lambda.Code.fromAsset('dist/src/lambda'),
handler: 'register.main',
});
const registerIntegration = new apigateway.LambdaIntegration(handler, {
requestTemplates: { 'application/json': '{ "statusCode": "200" }' },
});
const registerResource = api.root.addResource('register');
registerResource.addMethod('POST', registerIntegration);
}
}
tsconfig.json
{
"compilerOptions": {
"target": "ES2018",
"module": "commonjs",
"moduleResolution": "node",
"lib": ["es2018"],
"declaration": true,
"strict": true,
"noImplicitAny": false,
"strictNullChecks": true,
"noImplicitThis": true,
"alwaysStrict": true,
"esModuleInterop": true,
"noUnusedLocals": false,
"noUnusedParameters": false,
"noImplicitReturns": true,
"noFallthroughCasesInSwitch": false,
"inlineSourceMap": true,
"inlineSources": true,
"experimentalDecorators": true,
"strictPropertyInitialization": false,
"outDir": "dist",
"typeRoots": ["./node_modules/#types"]
},
"exclude": ["node_modules", "cdk.out", "./dist/**/*"]
}
And finally here is the script part of my package.json file:
"scripts": {
"build": "tsc",
"watch": "tsc -w",
"cdk": "cdk",
"bootstrap": "cdk bootstrap",
"deploy": "cdk deploy && rimraf cdk.out",
"destroy": "cdk destroy",
"run-same-local-fe-api": "sam local start-api -p 4000 -t ./template.yaml",
"dev": "npm run build && npm run synth && concurrently --kill-others \"npm run watch\" \"npm run run-same-local-fe-api\"",
"synth": "cdk synth --no-staging > template.yaml"
},
The problem
When I run npm run dev it compiles my typescript files to the dist folder in the same structure as what I have in my src folder (where all my typescript files live). I however run into the following error if I have any imports in my register.ts file:
{"errorType":"Runtime.ImportModuleError","errorMessage":"Error: Cannot
find module '../utils/forms'\nRequire stack:\n-
/var/task/register.js\n- /var/runtime/UserFunction.js\n-
/var/runtime/index.js","stack":["Runtime.ImportModuleError: Error:
Cannot find module '../utils/forms'","Require stack:","-
/var/task/register.js","- /var/runtime/UserFunction.js","-
/var/runtime/index.js"," at _loadUserApp
(/var/runtime/UserFunction.js:202:13)"," at
Object.module.exports.load (/var/runtime/UserFunction.js:242:17)","
at Object. (/var/runtime/index.js:43:30)"," at
Module._compile (internal/modules/cjs/loader.js:1085:14)"," at
Object.Module._extensions..js
(internal/modules/cjs/loader.js:1114:10)"," at Module.load
(internal/modules/cjs/loader.js:950:32)"," at Function.Module._load
(internal/modules/cjs/loader.js:790:12)"," at
Function.executeUserEntryPoint [as runMain]
(internal/modules/run_main.js:75:12)"," at
internal/main/run_main_module.js:17:47"]}
This happens for imports from relative local files (like '../utils/forms' as shown in the code above) but also for imports from node_modules. When I look into the compiled register.js file in the dist folder I see that it has made an attempt to parse the import:
"use strict";
var __importDefault = (this && this.__importDefault) || function (mod) {
return (mod && mod.__esModule) ? mod : { "default": mod };
};
Object.defineProperty(exports, "__esModule", { value: true });
const forms_1 = __importDefault(require("../utils/forms"));
const bucketName = process.env.BUCKET;
exports.main = async function (event, context) { ...
however it shows the error message above. I have tried using require instead of import but it was the same result...
Any help would be greatly appreciate! Thanks

Stated that this is really hard to answer without a minimal reproducible example; I would at least suggest to avoid any require and exports, and to use only import / export statements and following in tsconfig.json.
{
"compilerOptions": {
"module": "esnext"
}
}

Well.. I do understand that you want your main function to look something like this:
// final result written in javascript
exports.main = async function (event, context) {
return {
statusCode: 200,
};
}
But... using module.exports in Typescript is not the way to achieve that. Instead, Typescript using export directive (no s at the end of it) to define which parts of your code should be export. It's then up to your tsconfig.json file to determine which syntax will be used in order to represent this export (this is actually a part of Typescript engine)
So... a script written like this in Typescript
export async function main(event: any, context: any) {
return {
statusCode: 200,
};
}
Will be parse in Typescript as follow (I've used module: commonjs to achieve below result)
"use strict";
Object.defineProperty(exports, "__esModule", { value: true });
exports.main = void 0;
async function main(event, context) {
return {
statusCode: 200,
};
}
exports.main = main;
//# sourceMappingURL=test.js.map
Please note how the resulted js file correctly use modile.exports and main as you intended
In short: when using Typescript, please use the language directives and let the engine to do the rest for you. This way - a single source of code can be deployed for different environment without requireing changing your app logic. Neat!

Getting 'ReferenceError: document is not defined' only when I run webpack --watch?

Why would document stop being defined only when I run webpack --watch? When I run my build or dev script, compiling works great. It's only when I try and watch. New to WP.
My end goal here is to polyfill my client-side JS and auto-reload the browser window that LiveServer opens (VSCode plugin). Right now, I'm just trying to automatically compile my code after making changes which will trigger LiveServer to reload. Is there a better approach to this?
index.js
const errors = document.querySelector('.errors');
webpack.config.js
const path = require("path");
const MiniCssExtractPlugin = require("mini-css-extract-plugin");
const NodemonPlugin = require('nodemon-webpack-plugin');
const config = {
watch: true,
entry: {
rater_stater: "./src/index.js",
},
output: {
filename: "index.js",
path: path.resolve(__dirname, "dist"),
},
module: {
rules: [
{
test: /\.s[ac]ss$/i,
use: [
// Creates `style` nodes from JS strings
MiniCssExtractPlugin.loader,
// Translates CSS into CommonJS
"css-loader",
// Compiles Sass to CSS
"sass-loader",
"postcss-loader",
],
},
],
},
plugins: [
new MiniCssExtractPlugin({
// Options similar to the same options in webpackOptions.output
// both options are optional
filename: "style.css",
chunkFilename: "style-[id].css",
}),
new NodemonPlugin({
env: {
NODE_ENV: 'development',
},
})
],
};
module.exports = (env, argv) => {
if (argv.mode === "development") {
config.devtool = "source-map";
}
if (argv.mode === "production") {
config.module.rules.push({
test: /\.js?$/,
use: [
{
loader: "babel-loader",
options: {
presets: ["#babel/preset-env"],
},
},
],
exclude: /node_modules/,
});
}
return config;
};
package.json
"scripts": {
"build": "webpack --mode=production",
"dev": "webpack --mode=development",
"watch": "webpack --watch"
},
error
ReferenceError: document is not defined
at /Users/brad/Documents/vscode/rater-stater/dist/index.js:1:180375
at /Users/brad/Documents/vscode/rater-stater/dist/index.js:1:180732
at Object.<anonymous> (/Users/brad/Documents/vscode/rater-stater/dist/index.js:1:180735)
at Module._compile (internal/modules/cjs/loader.js:1138:30)
at Object.Module._extensions..js (internal/modules/cjs/loader.js:1158:10)
at Module.load (internal/modules/cjs/loader.js:986:32)
at Function.Module._load (internal/modules/cjs/loader.js:879:14)
at Function.executeUserEntryPoint [as runMain] (internal/modules/run_main.js:71:12)
at internal/main/run_main_module.js:17:47
[nodemon] app crashed - waiting for file changes before starting...
Edit:
I'm also getting this error when it does compile with webpack --mode=development. It's like my variables are all set to null? I'm so confused. Why would this happen? I've tried changing it from var to let to const and still get the same error.
Edit 2:
Ran a couple more tests. It's like everything related to document is broken.. but I can console.log document. I just can't use querySelector, etc.

All of these issues stopped when I wrapped my code with
document.addEventListener("DOMContentLoaded", function() {
...code
}
🤦

Using jquery in a shared webpack module, which is outside the webpack root

I have multiple layouts, which depend on some shared typescript files, thats why I want to share this files with multiple layouts which are using webpack.
I'm trying to include jquery in my ajax.ts and get this error:
ERROR in ../_shared/ajax.ts
Module not found: Error: Can't resolve 'jquery' in '{...}/layouts/_shared'
_shared/ajax.ts:
import * as $ from 'jquery';
export class AjaxListener {
constructor(){
// use jquery with $
}
}
layoutA/app.ts:
import { AjaxListener } from "../_shared/ajax";
import { App } from "../_shared/app";
let app = new App();
let ajaxListener = new AjaxListener();
My Folder Structure looks like this:
/layouts
/_shared
/ajax.ts
/app.ts
/layoutA
/app.ts
/webpack.config.js
/package.json (contains "#types/jquery": "^2.0.47" and "jquery": "^3.2.1")
/tsconfig.json
tsconfig.json:
{
"compilerOptions": {
"module": "es6",
"target": "es6",
"sourceMap": true
},
"exclude": [
"node_modules",
"typings/browser",
"typings/browser.d.ts",
"typings/main",
"typings/main.d.ts"
]
}
webpack.config.js:
const ExtractTextPlugin = require("extract-text-webpack-plugin");
var path = require("path");
var distPath = path.join(__dirname, "dist");
module.exports = [
{
entry: {
app: ['./app.sass', './app.ts']
},
resolve: {
extensions: [".tsx", ".js", ".ts", ".sass"]
},
cache: false,
output: {
path: distPath,
filename: "[name]_scripts.js"
},
module: {
rules : [
{
enforce: 'pre',
// "test" is commonly used to match the file extension
test: /\.js$/,
loader: "source-map-loader"
},
{
// "test" is commonly used to match the file extension
test: /\.tsx?$/,
exclude: [/node_modules/],
use: [ 'babel-loader', 'ts-loader' ]
},
{
test: /\.sass$/,
use: [
{
loader: "style-loader" // creates style nodes from JS strings
},{
loader: "css-loader", options: { sourceMap: true } // translates CSS into CommonJS
},{
loader: "sass-loader", options: { sourceMap: true } // compiles Sass to CSS
}
]
}
]
},
devtool: "eval"
}
]
If I try to import jquery inside layoutA/app.ts file (webpack root), it works fine. Since the ajax.ts lives outside this folder, which is the best way to import libraries like jquery, lodash etc. in these files?

The following points must be observed for the best way to load js libraries in your context:
Install every js library (e.g. jquery) with a package manager like npm
To each library it needs a TypeScript definitions file (e.g. #types/jquery, to find under npmjs.com)
Install this TypeScript definition file also with npm
Note every TypeScript definition in the tsconfig.json under "files" like
"files":[
"node_modules/#types/jquery/index.d.ts",
"node_modules/#types/requirejs/index.d.ts",
]
Do this compellingly (point 1-4) with the library requirejs. This is a js file and module loader.
Now you are ready to load the js library in the TypeScript main file like:
require(["jquery", "urijs"], function($, uri) {
// your code
});
Other notes:
In the index.html file: reference under the script tags only the js bundle files, builded by e.g. webpack.
Webpack needs a TypeScript loader.
Reference exported TypeScript classes in the tsconfig.json file under 'files' and also in the TypeScript file like:
import {Car} from "./classes/Car";
Hope it helps you, to get a proper structur!
Supplement:
Try the following: reference a js library in your ayax.ts like:
private example = require("./[path to npm library]/node_modules/test/src/test.js");
If you call the library name like 'test' in the require command, then its not possible to resolve 'test'. It try to resolve over the package.json and can not find it because its outside of the root.

Angular 4 universal app with #angular/cli with third party (library/component) compilation

I am trying to implement server side rendering using angular universal. With followed this post angular-4-universal-app-with-angular-cli and this cli-universal-demo project, I encountered a problem as below.
When node starts dist/server.js it shows an error:
(function (exports, require, module, __filename, __dirname)
{ export * from ‘./scn-filter-builder’
scn-filter-builder is my module. It's written in angular2/typescript and node.js doesn't understand it.
The question is that can I set to universal so it will compile packages from node_module to es5 by itself? Or I need to compile my component into es5?

So I ended up tackling something similar to this by compiling it with Webpack. I just added a webpack.config.js with the following:
const path = require('path');
const nodeExternals = require('webpack-node-externals');
module.exports = {
entry: {
server: './src/server.ts'
},
resolve: {
extensions: ['.ts', '.js']
},
target: 'node',
externals: [nodeExternals({
whitelist: [
/^ngx-bootstrap/
]
})],
node: {
__dirname: true
},
output: {
path: path.join(__dirname, 'server'),
filename: '[name].js',
libraryTarget: 'commonjs2'
},
module: {
rules: [
{ test: /\.ts$/, loader: 'ts-loader' }
]
}
}
Add the library that needs to be compiled in the nodeExternals -> whitelist area. In my case it was ngx-bootstrap. Then just run webpack to compile your file.

webpack val loader causing exceptions

I'm trying to dynamically include a .js file at webpack compile time.
I don't want to use a context to load environmental variables, because I don't these magic variables in my code.
What I'm trying to do is use the val loader to execute a module. There use an environment variable to decide what module to import. And export that module.
However, this is causing other loaders to throw errors.
Here's my dir layout
--base
--src
app.js
test.js
webpack.config.js
rawr.js
Here my webpack.config.js file
var path = require('path');
var webpack = require('webpack');
// var process = require('process');
var env = require(process.env.NODE_ENV || './devConf.js');
module.exports = {
// Specify logical root of the sourcecode
plugins: [
new webpack.DefinePlugin(env)
],
context: path.join(__dirname, '/src'),
entry: {
app: ['bootstrap.js'],
},
// Specify where to put the results
output: {
path: path.join(__dirname, '/dist'),
filename: 'build.js'
},
// Specify logical root of package imports so as to avoid relative path everywhere
resolve: {
root: path.join(__dirname, '/src'),
// What files we want to be able to import
extensions: ['', '.js', '.css', '.less'],
},
module: {
preLoaders: [
// Lint all js before compiling
/*{
test: /\.js$/,
exclude: /node_modules/,
loader: 'eslint-loader'
}*/
],
loaders: [
{
test: /\.js$/,
query: {
presets: ['es2015']
},
exclude: /node_modules/,
loader: 'babel'
},
{
test: /\.tpl\.html$/,
exclude: /node_modules/,
loader: 'ngtemplate?relativeTo=/src/!html'
},
{
test: /\.scss$/,
loaders: ["style", "css", "sass"]
},
{
test: /\.css$/,
loaders: ["style", "css"]
}
]
},
// Dev server settings
devServer: {
contentBase: path.join(__dirname, '/dist'),
noInfo: false,
hot: true
},
// ESLint config
eslint: {
configFile: path.join(__dirname, '.eslintrc')
}
};
My js files look like this
// app.js
let b = require('val!test.js');
// test.js
var process = require('process');
loadedModule = require(process.env.NODE_ENV) // NODE_ENV='./rawr.js'
export const myString = loadedModule
// rawr.js
module.exports.test = "hello world";
The exception I'm getting:
ERROR in ./src/app/app.js
Module parse failed: /home/smaug/Projects/angular-template/node_modules/babel-loader/index.js?{"presets":["es2015"]}!/home/smaug/Projects/angular-template/src/app/app.js Line 1: Unexpected identifier
You may need an appropriate loader to handle this file type.
| 'use strict';
|
| require('angular-animate');
# ./src/bootstrap.js 7:0-18
It has nothing to do with what I'm trying to do. But if I remove the require('val!...') statment, it goes away.
Any ideas?
UPDATE:
If I change the require statement to be
let b = require('val!./test.js');
I get the following error:
ERROR in ./~/val-loader!./src/app/test.js
Module build failed: Error: Final loader didn't return a Buffer or String
at DependenciesBlock.onModuleBuild (/home/smaug/Projects/angular-template/node_modules/webpack-core/lib/NormalModuleMixin.js:299:42)
at nextLoader (/home/smaug/Projects/angular-template/node_modules/webpack-core/lib/NormalModuleMixin.js:275:25)
at /home/smaug/Projects/angular-template/node_modules/webpack-core/lib/NormalModuleMixin.js:292:15
at runSyncOrAsync (/home/smaug/Projects/angular-template/node_modules/webpack-core/lib/NormalModuleMixin.js:160:12)
at nextLoader (/home/smaug/Projects/angular-template/node_modules/webpack-core/lib/NormalModuleMixin.js:290:3)
at /home/smaug/Projects/angular-template/node_modules/webpack-core/lib/NormalModuleMixin.js:292:15
at Object.context.callback (/home/smaug/Projects/angular-template/node_modules/webpack-core/lib/NormalModuleMixin.js:148:14)
at Object.module.exports (/home/

// app.js
let b = require('val!./test.js');

This is a very confusing Error Message..
Check for the following mishaps..
import statement is pointing to the exact file;
typo errors in the file name on import statement; importing the
modules which are not present.
check whether you have installed all
the loaders like
css-loader node-sass resolve-url-loader sass-loader\
style-loader url-loader
4.import statement is empty
ex:
import * from '';
5. Services and Providers returning nothing may also cause this error.

test.js is supposed to return a string that contains the code that is supposed to be given to the module that is requiring it. So, for your example, test.js should go from this
var process = require('process');
loadedModule = require(process.env.NODE_ENV) // NODE_ENV='./rawr.js'
export const myString = loadedModule
to this
var process = require('process')
loadedModule = require('raw-loader!' + process.env.NODE_ENV)
export const myString = loadedModule
Using the "raw-loader" you will get the text code from rawr.js rather than the value that rawr.js exports. "val-loader" will then give rawr.js's code to the require in app.js and it will load that text as if it was the text of the file that you were trying to load.
That was probably a terrible explanation, but just remember that when you use val-loader, you need to return a string containing code.