loopback-component-storage/example/providers.json

{
  "rackspace": {
    "username": "your-rackspace-username",
    "apiKey": "your-rackspace-api-key",
    "region": "DFW"
  },
  "amazon": {
    "key": "your-amazon-key",
    "keyId": "your-amazon-key-id"
  }
}