# Google Cloud Storage driver An implementation of the `storagedriver.StorageDriver` interface which uses Google Cloud for object storage. ## Parameters
Parameter Required Description
bucket yes Storage bucket name.
keyfile no A private service account key file in JSON format. Instead of a key file Google Application Default Credentials can be used.
rootdirectory no This is a prefix that will be applied to all Google Cloud Storage keys to allow you to segment data in your bucket if necessary.
`bucket`: The name of your Google Cloud Storage bucket where you wish to store objects (needs to already be created prior to driver initialization). `keyfile`: (optional) A private key file in JSON format, used for [Service Account Authentication](https://cloud.google.com/storage/docs/authentication#service_accounts). **Note** Instead of a key file you can use [Google Application Default Credentials](https://developers.google.com/identity/protocols/application-default-credentials). `rootdirectory`: (optional) The root directory tree in which all registry files will be stored. Defaults to the empty string (bucket root).