Firebase Functions in Monorepo

README.md

The firebase.json should be in the root of the workspace and it only shows the relevant bits.

Put the webpack config into modules/firebase/

Before deploying the functions, build the function bundle with webpack (it will end up in dist/).

firebase.json

{
  "functions": {
    "source": "modules/firebase/dist" 
  },
}

webpack.config.js

const path = require('path')

module.exports = {
  target: 'node',
  mode: 'production',
  entry: path.resolve(__dirname, 'src', 'index.ts'),
  module: {
    rules: [
      {
        test: /\.tsx?$/,
        use: 'ts-loader',
        exclude: /node_modules/,
      },
    ],
  },
  resolve: {
    extensions: ['.tsx', '.ts', '.mjs', '.js', '.json'],
  },
  output: {
    filename: 'index.js',
    path: path.resolve(__dirname, './dist'),
    libraryTarget: 'commonjs',
  },
  externals: {
    'firebase-admin': 'firebase-admin',
    'firebase-functions': 'firebase-functions',
  },
}