firebase.json

{
  "database": {
    "rules": "database.rules.json"
  },
  "functions": {
    "source": "packages/functions",
    "predeploy": [
      "npm --prefix \"$RESOURCE_DIR\" run pre-deploy",
      "npm --prefix \"$RESOURCE_DIR\" run build"
    ],
    "postdeploy": [
      "npm --prefix \"$RESOURCE_DIR\" run post-deploy"
    ],
    "ignore": [
      "**/node_modules",
      "**/*.log"
    ]
  },
  "hosting": {
    "public": "packages/frontend/build",
    "ignore": [
      "firebase.json",
      "**/.*",
      "**/node_modules/**"
    ],
    "rewrites": [
      {
        "source": "**",
        "destination": "/index.html"
      }
    ]
  },
  "emulators": {
    "functions": {
      "port": 5001
    },
    "database": {
      "port": 9000
    },
    "hosting": {
      "port": 5000,
      "host": "0.0.0.0"
    },
    "pubsub": {},
    "ui": {
      "enabled": true
    }
  }
}