anchor.diff:  
   `project_id`::
   
  -    The Google Cloud project id. This will be automatically infered from the credentials file but
  +    The Google Cloud project id. This will be automatically inferred from the credentials file but
       can be specified explicitly. For example, it can be used to switch between projects when the
       same credentials are usable for both the production and the development projects.
   
  
positive.code: // TEST[skip:we don't have gcs setup while testing this]
  
  The `credentials_file` settings are {ref}/secure-settings.html#reloadable-secure-settings[reloadable].
  After you reload the settings, the internal `gcs` clients, used to transfer the
  snapshot contents, will utilize the latest settings from the keystore.
  
  
  NOTE: In progress snapshot/restore jobs will not be preempted by a *reload*
  of the client's `credentials_file` settings. They will complete using the client
  as it was built when the operation started.
  
  [[repository-gcs-client]]
  ==== Client Settings
  
  The client used to connect to Google Cloud Storage has a number of settings available.
  Client setting names are of the form `gcs.client.CLIENT_NAME.SETTING_NAME` and specified
  inside `elasticsearch.yml`. The default client name looked up by a `gcs` repository is
  called `default`, but can be customized with the repository setting `client`.
  
  
negative.code: [[repository-gcs-usage]]
  ==== Getting started
  
  The plugin uses the https://github.com/GoogleCloudPlatform/google-cloud-java/tree/master/google-cloud-clients/google-cloud-storage[Google Cloud Java Client for Storage]
  to connect to the Storage service. If you are using  
  https://cloud.google.com/storage/[Google Cloud Storage] for the first time, you 
  must connect to the https://console.cloud.google.com/[Google Cloud Platform Console]
  and create a new project. After your project is created, you must enable the
  Cloud Storage Service for your project.
  
  [[repository-gcs-creating-bucket]]
  ===== Creating a Bucket
  
  The Google Cloud Storage service uses the concept of a 
  https://cloud.google.com/storage/docs/key-terms[bucket] as a container for all 
  the data. Buckets are usually created using the 
  https://console.cloud.google.com/[Google Cloud Platform Console]. The plugin 
  does not automatically create buckets.
  
  To create a new bucket:
  
  1. Connect to the https://console.cloud.google.com/[Google Cloud Platform Console].
  2. Select your project.
  3. Go to the https://console.cloud.google.com/storage/browser[Storage Browser].
  4. Click the *Create Bucket* button.
  5. Enter the name of the new bucket.
  6. Select a storage class.
  7. Select a location.
  8. Click the *Create* button.
  
  For more detailed instructions, see the
  https://cloud.google.com/storage/docs/quickstart-console#create_a_bucket[Google Cloud documentation].
  
  [[repository-gcs-service-authentication]]
  ===== Service Authentication
  
  The plugin must authenticate the requests it makes to the Google Cloud Storage 
  service. It is common for Google client libraries to employ a strategy named https://cloud.google.com/docs/authentication/production#providing_credentials_to_your_application[application default credentials].
  However, that strategy is **not** supported for use with Elasticsearch. The 
  plugin operates under the Elasticsearch process, which runs with the security 
  manager enabled. The security manager obstructs the "automatic" credential discovery.
  Therefore, you must configure <<repository-gcs-using-service-account,service account>> 
  credentials even if you are using an environment that does not normally require
  this configuration (such as Compute Engine, Kubernetes Engine or App Engine).
  
  [[repository-gcs-using-service-account]]
  ===== Using a Service Account
  You have to obtain and provide https://cloud.google.com/iam/docs/overview#service_account[service account credentials]
  manually.
  
  For detailed information about generating JSON service account files, see the  https://cloud.google.com/storage/docs/authentication?hl=en#service_accounts[Google Cloud documentation].
  Note that the PKCS12 format is not supported by this plugin.
  
  Here is a summary of the steps:
  
  1. Connect to the https://console.cloud.google.com/[Google Cloud Platform Console].
  2. Select your project.
  3. Got to the https://console.cloud.google.com/permissions[Permission] tab.
  4. Select the https://console.cloud.google.com/permissions/serviceaccounts[Service Accounts] tab.
  5. Click *Create service account*.
  6. After the account is created, select it and download a JSON key file. 
  
  A JSON service account file looks like this:
  
  [source,js]
  ----
  