google.golang.org/cloud (go): Package cloud is the root of the packages used to access Google Cloud Services. See https://godoc.org/cloud.google.com/go for a full list of sub-packages.  All clients in sub-packages are configurable via client options. These options are described here: https://godoc.org/google.golang.org/api/option.  All the clients in sub-packages support authentication via Google Application Default Credentials (see https://cloud.google.com/docs/authentication/production), or by providing a JSON key file for a Service Account. See the authentication examples in this package for details.  By default, all requests in sub-packages will run indefinitely, retrying on transient errors when correctness allows. To set timeouts or arrange for cancellation, use contexts. See the examples for details.  Do not attempt to control the initial connection (dialing) of a service by setting a timeout on the context passed to NewClient. Dialing is non-blocking, so timeouts would be ineffective and would only interfere with credential refreshing, which uses the same context.  Connection pooling differs in clients based on their transport. Cloud clients either rely on HTTP or gRPC transports to communicate with Google Cloud.  Cloud clients that use HTTP (bigquery, compute, storage, and translate) rely on the underlying HTTP transport to cache connections for later re-use. These are cached to the default http.MaxIdleConns and http.MaxIdleConnsPerHost settings in http.DefaultTransport.  For gRPC clients (all others in this repo), connection pooling is configurable. Users of cloud client libraries may specify option.WithGRPCConnectionPool(n) as a client option to NewClient calls. This configures the underlying gRPC connections to be pooled and addressed in a round robin fashion.  Minimal docker images like Alpine lack CA certificates. This causes RPCs to appear to hang, because gRPC retries indefinitely. See https://github.com/GoogleCloudPlatform/google-cloud-go/issues/928 for more information.  To see gRPC logs, set the environment variable GRPC_GO_LOG_SEVERITY_LEVEL. See https://godoc.org/google.golang.org/grpc/grpclog for more information.  For HTTP logging, set the GODEBUG environment variable to "http2debug=1" or "http2debug=2".  Google Application Default Credentials is the recommended way to authorize and authenticate clients.  For information on how to create and obtain Application Default Credentials, see https://developers.google.com/identity/protocols/application-default-credentials.   To arrange for an RPC to be canceled, use context.WithCancel.   You can use a file with credentials to authenticate and authorize, such as a JSON key file associated with a Google service account. Service Account keys can be created and downloaded from https://console.developers.google.com/permissions/serviceaccounts.  This example uses the Datastore client, but the same steps apply to the other client libraries underneath this package.   In some cases (for instance, you don't want to store secrets on disk), you can create credentials from in-memory JSON and use the WithCredentials option.  The google package in this example is at golang.org/x/oauth2/google.  This example uses the PubSub client, but the same steps apply to the other client libraries underneath this package.   To set a timeout for an RPC, use context.WithTimeout.
Keywords: cloud-bigquery|cloud-datastore|cloud-pubsub|cloud-storage|go|golang|google-cloud