Watching for changes with docker-compose

.babelrc

{
  "presets": [
    [
      "@babel/preset-env",
      {
        "targets": {
          "node": "current"
        }
      }
    ],
    "@babel/preset-flow"
  ],
  "plugins": [
    "@babel/plugin-proposal-class-properties",
    "@babel/plugin-proposal-object-rest-spread",
    "babel-plugin-dynamic-import-node",
    "@babel/plugin-transform-destructuring",
    "@babel/plugin-transform-runtime"
  ]
}

.dockerignore

npm-debug.log
node_modules/

docker-compose.yml

version: '3'
services:

  my-api:
    build:
      context: .
      dockerfile: Dockerfile
    # Assumes there's a "watch" script in the package.json
    command: ["yarn", "run", "watch"] 
    environment:
      NODE_ENV: "local"
      PG_HOST: "postgres"
      PG_PORT: 5432
      PG_DB_NAME: "my_api_db"
      PG_DB_USER: "mydb_user"
    volumes:
      # Here is where we can mount the host
      # directory at ./src into the container
      - ./src:/apps/my-api/src
    depends_on:
      - postgres
    ports:
      - "4000:4000"

  postgres:
    image: postgres:11.3-alpine
    environment:
      POSTGRES_DB: my_api_db
      POSTGRES_USER: mydb_user
    volumes:
      - pg-data:/var/lib/postgresql/data # Persist DB data
    ports:
      - "5432:5432"

volumes:
  pg-data:

Dockerfile

FROM node:10.15.3-alpine

ENV APPS_DIR=/apps
ENV APP_NAME=my-api
ENV APP_PATH=${APPS_DIR}/${APP_NAME}

# Set the working directory
WORKDIR ${APP_PATH}

# Copy the package.json, yarn.lock, .babelrc,
# and src/ directory into the container
COPY package.json ./
COPY yarn.lock ./
COPY .babelrc ./
COPY src/ src/

# Install the application dependencies
# and transpile to flow source
RUN \
  yarn install &&\
  yarn run build

EXPOSE 4000

# Default to running "watch" script
CMD ["yarn", "run", "watch"]

package.json

{
  "name": "my-api",
  "version": "0.1.0",
  "description": "The api gateway used for retrieving data resources",
  "author": "Sean Costello <me@seancostello.io>",
  "license": "ISC",
  "scripts": {
    "watch": "npm-watch restart",
    "restart": "npm run build && npm start",
    "build": "rm -rf lib/ && babel src/ -d lib/ && flow-copy-source src/ lib/",
    "test": "npm run eslint && npm run mocha",
    "start": "babel-node lib/",
    "mocha": "nyc mocha --require babel-core/register {src,test}/**/*.{spec,test}.js --recursive --exit",
    "flow": "flow"
  },
  "watch": {
    "restart": {
      "patterns": [
        "src"
      ],
      "extensions": "js",
      "quiet": false,
      "legacyWatch": true,
      "delay": 2000,
      "runOnChangeOnly": false
    }
  },
  "dependencies": {
    "express": "^4.16.4",
    "massive": "^5.8.0",
    "npm-watch": "^0.6.0",
    "ramda": "^0.26.1",
    "rxjs": "^6.5.2"
  },
  "devDependencies": {
    "@babel/cli": "^7.4.4",
    "@babel/core": "^7.4.4",
    "@babel/node": "^7.2.2",
    "@babel/plugin-proposal-class-properties": "^7.4.4",
    "@babel/plugin-proposal-object-rest-spread": "^7.4.4",
    "@babel/plugin-transform-destructuring": "^7.4.4",
    "@babel/plugin-transform-runtime": "^7.4.4",
    "@babel/preset-env": "^7.4.4",
    "@babel/preset-flow": "^7.0.0",
    "@babel/register": "^7.4.4",
    "@babel/runtime": "^7.4.4",
    "babel-plugin-dynamic-import-node": "^2.2.0",
    "chai": "^4.2.0",
    "flow-copy-source": "^2.0.4",
    "mocha": "^6.1.4",
    "nyc": "^14.1.1"
  }
}