Why is webpack not including the node_module libraries in the build when they are imported into the index file?
webpack is still a bit of a black art for me that I have not fully grasped, so below is an explanation of that I am trying to achieve.
I am building a test application to run as serverless code on an AWS Lambda Node server. The goal is to keep the deployment package a small as possible by having 1 or more chunks and no node_modules folder on the server.
I am writing in Typescript v3 and using webpack v4 to create a bundle for the server.
Here is my directory structure:
- dist/
- node_modules/
- src/index.ts
- package.json
- tsconfig.json
- tslint.json
- webpack.config.js
here is an excerpt from my package.json
"dependencies": {
"moment": "^2.22.2"
},
"devDependencies": {
"@types/aws-lambda": "^8.10.15",
"@types/node": "^10.12.2",
"awesome-typescript-loader": "^5.2.1",
"aws-lambda": "^0.1.2",
"source-map-loader": "^0.2.4",
"ts-node": "^7.0.1",
"tslint": "^5.11.0",
"tslint-loader": "^3.5.4",
"typescript": "^3.1.6",
"webpack": "^4.25.1",
"webpack-bundle-analyzer": "^3.0.3",
"webpack-cli": "^3.1.2",
"webpack-node-externals": "^1.7.2"
}
my index.ts that I am trying to bundle:
import { Handler } from "aws-lambda";
import moment from "moment";
const handler: Handler = async ( event: any ) => {
const stamp = moment().format( "x" );
console.log( `process: ${ process.env.NAME } called at ${ stamp }` );
console.log( event );
return {
body: "process completed",
statusCode: 200
};
};
export { handler };
my tsconfig.json:
{
"compilerOptions": {
"outDir": "./dist",
"sourceMap": true,
"noImplicitAny": true,
"module": "commonjs",
"target": "es5",
"allowJs": true,
"pretty": false,
"removeComments": true,
"esModuleInterop": true,
"moduleResolution": "node",
"types": [
"node"
],
"lib": [
"es5",
"es6",
"dom"
]
},
"include": [
"src/**/*.ts"
],
"exclude": [
"node_modules"
]
}
finally here is my webpack.config.js:
const path = require( "path" );
const UglifyJSPlugin = require( "uglifyjs-webpack-plugin" );
const nodeExternals = require( "webpack-node-externals" );
const ROOT = path.resolve( __dirname, "src" );
const DESTINATION = path.resolve( __dirname, "dist" );
module.exports = {
context: ROOT,
mode: "production",
entry: {
index: "./index.ts"
},
target: "node",
externals: [ nodeExternals() ],
optimization: {
minimizer: [
new UglifyJSPlugin( {
uglifyOptions: {
compress: true,
mangle: false,
toplevel: false,
keep_classnames: true,
keep_fnames: true
}
} )
],
splitChunks: {
cacheGroups: {
node_vendors: {
test: /[\\/]node_modules[\\/]/,
chunks: "all",
priority: 1
}
}
}
},
output: {
filename: "[name].js",
libraryTarget: "commonjs2",
path: DESTINATION
},
resolve: {
extensions: [ ".ts", ".js" ],
modules: [ ROOT, "node_modules" ]
},
module: {
rules: [
{
enforce: "pre",
test: /\.js$/,
use: "source-map-loader"
},
{
enforce: "pre",
test: /\.ts$/,
exclude: /node_modules/,
use: "tslint-loader"
},
{
test: /\.ts$/,
exclude: [ /node_modules/ ],
use: "awesome-typescript-loader"
}
]
},
devtool: "cheap-module-source-map",
devServer: {}
};
When I run webpack I get the following console output:
Version: webpack 4.25.1
Time: 4856ms
Built at: 2018-11-08 15:41:09
Asset Size Chunks Chunk Names
index.js 3.83 KiB 0 [emitted] index
Entrypoint index = index.js
[0] ./index.ts 3.11 KiB {0} [built]
[1] external "moment" 42 bytes {0} [built]
When I deploy this to AWS Lambda I and call the function I get the following error:
{
"errorMessage": "Cannot find module 'moment'",
"errorType": "Error",
"stackTrace": [
"Function.Module._load (module.js:474:25)",
"Module.require (module.js:596:17)",
"require (internal/module.js:11:18)",
"Object.<anonymous> (/var/task/index.js:1:3963)",
"__webpack_require__ (/var/task/index.js:1:323)",
"Object.<anonymous> (/var/task/index.js:1:3595)",
"__webpack_require__ (/var/task/index.js:1:323)",
"module.exports.__awaiter.__awaiter.P (/var/task/index.js:1:1650)",
"Object.<anonymous> (/var/task/index.js:1:1695)"
]
}
