README

Google Cloud Client Libraries for Go

GoDoc

Go packages for Google Cloud Platform services.

import "cloud.google.com/go"

To install the packages on your system, do not clone the repo. Instead use

$ go get -u cloud.google.com/go/...

NOTE: Some of these packages are under development, and may occasionally make backwards-incompatible changes.

NOTE: Github repo is a mirror of https://code.googlesource.com/gocloud.

News

7 August 2018

As of November 1, the code in the repo will no longer support Go versions 1.8 and earlier. No one other than AppEngine users should be on those old versions, and AppEngine Standard and Flex will stop supporting new deployments with those versions on that date.

Changes have been moved to CHANGES.

Supported APIs

Google API Status Package
Asset alpha godoc.org/cloud.google.com/go/asset/v1beta
BigQuery stable godoc.org/cloud.google.com/go/bigquery
Bigtable stable godoc.org/cloud.google.com/go/bigtable
Cloudtasks beta godoc.org/cloud.google.com/go/cloudtasks/apiv2beta3
Container stable godoc.org/cloud.google.com/go/container/apiv1
ContainerAnalysis beta godoc.org/cloud.google.com/go/containeranalysis/apiv1beta1
Dataproc stable godoc.org/cloud.google.com/go/dataproc/apiv1
Datastore stable godoc.org/cloud.google.com/go/datastore
Debugger alpha godoc.org/cloud.google.com/go/debugger/apiv2
Dialogflow alpha godoc.org/cloud.google.com/go/dialogflow/apiv2
Data Loss Prevention alpha godoc.org/cloud.google.com/go/dlp/apiv2
ErrorReporting alpha godoc.org/cloud.google.com/go/errorreporting
Firestore beta godoc.org/cloud.google.com/go/firestore
IAM stable godoc.org/cloud.google.com/go/iam
KMS stable godoc.org/cloud.google.com/go/kms
Natural Language stable godoc.org/cloud.google.com/go/language/apiv1
Logging stable godoc.org/cloud.google.com/go/logging
Monitoring alpha godoc.org/cloud.google.com/go/monitoring/apiv3
OS Login alpha cloud.google.com/compute/docs/oslogin/rest
Pub/Sub stable godoc.org/cloud.google.com/go/pubsub
Memorystore stable godoc.org/cloud.google.com/go/redis/apiv1beta1
Spanner stable godoc.org/cloud.google.com/go/spanner
Speech stable godoc.org/cloud.google.com/go/speech/apiv1
Storage stable godoc.org/cloud.google.com/go/storage
Text To Speech alpha godoc.org/cloud.google.com/go/texttospeech/apiv1
Trace alpha godoc.org/cloud.google.com/go/trace/apiv2
Translation stable godoc.org/cloud.google.com/go/translate
Video Intelligence alpha godoc.org/cloud.google.com/go/videointelligence/apiv1beta1
Vision stable godoc.org/cloud.google.com/go/vision/apiv1

Alpha status: the API is still being actively developed. As a result, it might change in backward-incompatible ways and is not recommended for production use.

Beta status: the API is largely complete, but still has outstanding features and bugs to be addressed. There may be minor backwards-incompatible changes where necessary.

Stable status: the API is mature and ready for production use. We will continue addressing bugs and feature requests.

Documentation and examples are available at https://godoc.org/cloud.google.com/go

Visit or join the google-api-go-announce group for updates on these packages.

Go Versions Supported

We support the two most recent major versions of Go. If Google App Engine uses an older version, we support that as well.

Authorization

By default, each API will use Google Application Default Credentials for authorization credentials used in calling the API endpoints. This will allow your application to run in many environments without requiring explicit configuration.

client, err := storage.NewClient(ctx)

To authorize using a JSON key file, pass option.WithCredentialsFile to the NewClient function of the desired package. For example:

client, err := storage.NewClient(ctx, option.WithCredentialsFile("path/to/keyfile.json"))

You can exert more control over authorization by using the golang.org/x/oauth2 package to create an oauth2.TokenSource. Then pass option.WithTokenSource to the NewClient function: snip:# (auth-ts)

tokenSource := ...
client, err := storage.NewClient(ctx, option.WithTokenSource(tokenSource))

Cloud Datastore GoDoc

Example Usage

First create a datastore.Client to use throughout your application:

client, err := datastore.NewClient(ctx, "my-project-id")
if err != nil {
	log.Fatal(err)
}

Then use that client to interact with the API:

type Post struct {
	Title       string
	Body        string `datastore:",noindex"`
	PublishedAt time.Time
}
keys := []*datastore.Key{
	datastore.NameKey("Post", "post1", nil),
	datastore.NameKey("Post", "post2", nil),
}
posts := []*Post{
	{Title: "Post 1", Body: "...", PublishedAt: time.Now()},
	{Title: "Post 2", Body: "...", PublishedAt: time.Now()},
}
if _, err := client.PutMulti(ctx, keys, posts); err != nil {
	log.Fatal(err)
}

Cloud Storage GoDoc

Example Usage

First create a storage.Client to use throughout your application:

client, err := storage.NewClient(ctx)
if err != nil {
	log.Fatal(err)
}
// Read the object1 from bucket.
rc, err := client.Bucket("bucket").Object("object1").NewReader(ctx)
if err != nil {
	log.Fatal(err)
}
defer rc.Close()
body, err := ioutil.ReadAll(rc)
if err != nil {
	log.Fatal(err)
}

Cloud Pub/Sub GoDoc

Example Usage

First create a pubsub.Client to use throughout your application:

client, err := pubsub.NewClient(ctx, "project-id")
if err != nil {
	log.Fatal(err)
}

Then use the client to publish and subscribe:

// Publish "hello world" on topic1.
topic := client.Topic("topic1")
res := topic.Publish(ctx, &pubsub.Message{
	Data: []byte("hello world"),
})
// The publish happens asynchronously.
// Later, you can get the result from res:
...
msgID, err := res.Get(ctx)
if err != nil {
	log.Fatal(err)
}

// Use a callback to receive messages via subscription1.
sub := client.Subscription("subscription1")
err = sub.Receive(ctx, func(ctx context.Context, m *pubsub.Message) {
	fmt.Println(m.Data)
	m.Ack() // Acknowledge that we've consumed the message.
})
if err != nil {
	log.Println(err)
}

BigQuery GoDoc

Example Usage

First create a bigquery.Client to use throughout your application: snip:# (bq-1)

c, err := bigquery.NewClient(ctx, "my-project-ID")
if err != nil {
	// TODO: Handle error.
}

Then use that client to interact with the API: snip:# (bq-2)

// Construct a query.
q := c.Query(`
    SELECT year, SUM(number)
    FROM [bigquery-public-data:usa_names.usa_1910_2013]
    WHERE name = "William"
    GROUP BY year
    ORDER BY year
`)
// Execute the query.
it, err := q.Read(ctx)
if err != nil {
	// TODO: Handle error.
}
// Iterate through the results.
for {
	var values []bigquery.Value
	err := it.Next(&values)
	if err == iterator.Done {
		break
	}
	if err != nil {
		// TODO: Handle error.
	}
	fmt.Println(values)
}

Stackdriver Logging GoDoc

Example Usage

First create a logging.Client to use throughout your application: snip:# (logging-1)

ctx := context.Background()
client, err := logging.NewClient(ctx, "my-project")
if err != nil {
	// TODO: Handle error.
}

Usually, you'll want to add log entries to a buffer to be periodically flushed (automatically and asynchronously) to the Stackdriver Logging service. snip:# (logging-2)

logger := client.Logger("my-log")
logger.Log(logging.Entry{Payload: "something happened!"})

Close your client before your program exits, to flush any buffered log entries. snip:# (logging-3)

err = client.Close()
if err != nil {
	// TODO: Handle error.
}

Cloud Spanner GoDoc

Example Usage

First create a spanner.Client to use throughout your application:

client, err := spanner.NewClient(ctx, "projects/P/instances/I/databases/D")
if err != nil {
	log.Fatal(err)
}
// Simple Reads And Writes
_, err = client.Apply(ctx, []*spanner.Mutation{
	spanner.Insert("Users",
		[]string{"name", "email"},
		[]interface{}{"alice", "a@example.com"})})
if err != nil {
	log.Fatal(err)
}
row, err := client.Single().ReadRow(ctx, "Users",
	spanner.Key{"alice"}, []string{"email"})
if err != nil {
	log.Fatal(err)
}

Contributing

Contributions are welcome. Please, see the CONTRIBUTING document for details. We're using Gerrit for our code reviews. Please don't open pull requests against this repo, new pull requests will be automatically closed.

Please note that this project is released with a Contributor Code of Conduct. By participating in this project you agree to abide by its terms. See Contributor Code of Conduct for more information.

Expand ▾ Collapse ▴

Documentation

Overview

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.

Client Options

All clients in sub-packages are configurable via client options. These options are described here: https://godoc.org/google.golang.org/api/option.

Authentication and Authorization

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.

Timeouts and Cancellation

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

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.

Using the Libraries with Docker

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.

Debugging

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".

Example (ApplicationDefaultCredentials)

    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.

    Output:
    
    
    Example (Cancellation)

      To arrange for an RPC to be canceled, use context.WithCancel.

      Output:
      
      
      Example (CredentialsFile)

        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.

        Output:
        
        
        Example (CredentialsFromJSON)

          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.

          Output:
          
          
          Example (Timeout)

            To set a timeout for an RPC, use context.WithTimeout.

            Output:
            
            

            Source Files

            Directories

            Path Synopsis
            asset
            apiv1beta1
            Package asset is an auto-generated package for the Cloud Asset API.
            Package asset is an auto-generated package for the Cloud Asset API.
            v1beta1
            Package asset is an auto-generated package for the Cloud Asset API.
            Package asset is an auto-generated package for the Cloud Asset API.
            Package bigquery provides a client for the BigQuery service.
            Package bigquery provides a client for the BigQuery service.
            datatransfer/apiv1
            Package datatransfer is an auto-generated package for the BigQuery Data Transfer API.
            Package datatransfer is an auto-generated package for the BigQuery Data Transfer API.
            Package bigtable is an API to Google Cloud Bigtable.
            Package bigtable is an API to Google Cloud Bigtable.
            bttest
            Package bttest contains test helpers for working with the bigtable package.
            Package bttest contains test helpers for working with the bigtable package.
            cmd/cbt
            Cbt is a tool for doing basic interactions with Cloud Bigtable.
            Cbt is a tool for doing basic interactions with Cloud Bigtable.
            cmd/emulator
            cbtemulator launches the in-memory Cloud Bigtable server on the given address.
            cbtemulator launches the in-memory Cloud Bigtable server on the given address.
            cmd/loadtest
            Loadtest does some load testing through the Go client library for Cloud Bigtable.
            Loadtest does some load testing through the Go client library for Cloud Bigtable.
            cmd/scantest
            Scantest does scan-related load testing against Cloud Bigtable.
            Scantest does scan-related load testing against Cloud Bigtable.
            Package civil implements types for civil time, a time-zone-independent representation of time that follows the rules of the proleptic Gregorian calendar with exactly 24-hour days, 60-minute hours, and 60-second minutes.
            Package civil implements types for civil time, a time-zone-independent representation of time that follows the rules of the proleptic Gregorian calendar with exactly 24-hour days, 60-minute hours, and 60-second minutes.
            cloudtasks
            apiv2beta2
            Package cloudtasks is an auto-generated package for the Cloud Tasks API.
            Package cloudtasks is an auto-generated package for the Cloud Tasks API.
            apiv2beta3
            Package cloudtasks is an auto-generated package for the Cloud Tasks API.
            Package cloudtasks is an auto-generated package for the Cloud Tasks API.
            cmd
            compute
            metadata
            Package metadata provides access to Google Compute Engine (GCE) metadata and API service accounts.
            Package metadata provides access to Google Compute Engine (GCE) metadata and API service accounts.
            Package container contains a deprecated Google Container Engine client.
            Package container contains a deprecated Google Container Engine client.
            apiv1
            Package container is an auto-generated package for the Google Container Engine API.
            Package container is an auto-generated package for the Google Container Engine API.
            containeranalysis
            apiv1beta1
            Package containeranalysis is an auto-generated package for the Container Analysis API.
            Package containeranalysis is an auto-generated package for the Container Analysis API.
            dataproc
            apiv1
            Package dataproc is an auto-generated package for the Google Cloud Dataproc API.
            Package dataproc is an auto-generated package for the Google Cloud Dataproc API.
            apiv1beta2
            Package dataproc is an auto-generated package for the Google Cloud Dataproc API.
            Package dataproc is an auto-generated package for the Google Cloud Dataproc API.
            Package datastore provides a client for Google Cloud Datastore.
            Package datastore provides a client for Google Cloud Datastore.
            debugger
            apiv2
            Package debugger is an auto-generated package for the Stackdriver Debugger API.
            Package debugger is an auto-generated package for the Stackdriver Debugger API.
            dialogflow
            apiv2
            Package dialogflow is an auto-generated package for the Dialogflow API.
            Package dialogflow is an auto-generated package for the Dialogflow API.
            dlp
            apiv2
            Provides methods for detection, risk analysis, and de-identification of privacy-sensitive fragments in text, images, and Google Cloud Platform storage repositories.
            Provides methods for detection, risk analysis, and de-identification of privacy-sensitive fragments in text, images, and Google Cloud Platform storage repositories.
            Package errorreporting is a Google Stackdriver Error Reporting library.
            Package errorreporting is a Google Stackdriver Error Reporting library.
            apiv1beta1
            Package errorreporting is an auto-generated package for the Stackdriver Error Reporting API.
            Package errorreporting is an auto-generated package for the Stackdriver Error Reporting API.
            expr
            apiv1alpha1
            Package expr is an auto-generated package for the Common Expression Language.
            Package expr is an auto-generated package for the Common Expression Language.
            Package firestore provides a client for reading and writing to a Cloud Firestore database.
            Package firestore provides a client for reading and writing to a Cloud Firestore database.
            apiv1beta1
            Package firestore is an auto-generated package for the Google Cloud Firestore API.
            Package firestore is an auto-generated package for the Google Cloud Firestore API.
            functions
            metadata
            Package metadata provides methods for creating and accessing context.Context objects with Google Cloud Functions metadata.
            Package metadata provides methods for creating and accessing context.Context objects with Google Cloud Functions metadata.
            Package httpreplay provides an API for recording and replaying traffic from HTTP-based Google API clients.
            Package httpreplay provides an API for recording and replaying traffic from HTTP-based Google API clients.
            iam
            Package iam supports the resource-specific operations of Google Cloud IAM (Identity and Access Management) for the Google Cloud Libraries.
            Package iam supports the resource-specific operations of Google Cloud IAM (Identity and Access Management) for the Google Cloud Libraries.
            admin/apiv1
            Package admin is an auto-generated package for the Google Identity and Access Management (IAM) API.
            Package admin is an auto-generated package for the Google Identity and Access Management (IAM) API.
            credentials/apiv1
            Package credentials is an auto-generated package for the IAM Service Account Credentials API.
            Package credentials is an auto-generated package for the IAM Service Account Credentials API.
            kms
            apiv1
            Manages keys and performs cryptographic operations in a central cloud service, for direct use by other cloud resources and applications.
            Manages keys and performs cryptographic operations in a central cloud service, for direct use by other cloud resources and applications.
            language
            apiv1
            Google Cloud Natural Language API provides natural language understanding technologies to developers.
            Google Cloud Natural Language API provides natural language understanding technologies to developers.
            apiv1beta2
            Package language is an auto-generated package for the Google Cloud Natural Language API.
            Package language is an auto-generated package for the Google Cloud Natural Language API.
            Package logging contains a Stackdriver Logging client suitable for writing logs.
            Package logging contains a Stackdriver Logging client suitable for writing logs.
            apiv2
            Package logging is an auto-generated package for the Stackdriver Logging API.
            Package logging is an auto-generated package for the Stackdriver Logging API.
            logadmin
            Package logadmin contains a Stackdriver Logging client that can be used for reading logs and working with sinks, metrics and monitored resources.
            Package logadmin contains a Stackdriver Logging client that can be used for reading logs and working with sinks, metrics and monitored resources.
            Package longrunning supports Long Running Operations for the Google Cloud Libraries.
            Package longrunning supports Long Running Operations for the Google Cloud Libraries.
            autogen
            Package longrunning is an auto-generated package for the Google Long Running Operations API.
            Package longrunning is an auto-generated package for the Google Long Running Operations API.
            monitoring
            apiv3
            Package monitoring is an auto-generated package for the Stackdriver Monitoring API.
            Package monitoring is an auto-generated package for the Stackdriver Monitoring API.
            oslogin
            apiv1
            Package oslogin is an auto-generated package for the Google Cloud OS Login API.
            Package oslogin is an auto-generated package for the Google Cloud OS Login API.
            apiv1beta
            Package oslogin is an auto-generated package for the Google Cloud OS Login API.
            Package oslogin is an auto-generated package for the Google Cloud OS Login API.
            Package profiler is a client for the Stackdriver Profiler service.
            Package profiler is a client for the Stackdriver Profiler service.
            busybench
            Busybench is a tool that runs a benchmark with the profiler enabled.
            Busybench is a tool that runs a benchmark with the profiler enabled.
            mocks
            Package mocks is a generated GoMock package.
            Package mocks is a generated GoMock package.
            Package pubsub provides an easy way to publish and receive Google Cloud Pub/Sub messages, hiding the details of the underlying server RPCs.
            Package pubsub provides an easy way to publish and receive Google Cloud Pub/Sub messages, hiding the details of the underlying server RPCs.
            apiv1
            Package pubsub is an auto-generated package for the Google Cloud Pub/Sub API.
            Package pubsub is an auto-generated package for the Google Cloud Pub/Sub API.
            loadtest
            Package loadtest implements load testing for pubsub, following the interface defined in https://github.com/GoogleCloudPlatform/pubsub/tree/master/load-test-framework/ .
            Package loadtest implements load testing for pubsub, following the interface defined in https://github.com/GoogleCloudPlatform/pubsub/tree/master/load-test-framework/ .
            loadtest/pb
            Package google_pubsub_loadtest is a generated protocol buffer package.
            Package google_pubsub_loadtest is a generated protocol buffer package.
            pstest
            Package pstest provides a fake Cloud PubSub service for testing.
            Package pstest provides a fake Cloud PubSub service for testing.
            redis
            apiv1
            The Google Cloud Memorystore for Redis API is used for creating and managing Redis instances on the Google Cloud Platform.
            The Google Cloud Memorystore for Redis API is used for creating and managing Redis instances on the Google Cloud Platform.
            apiv1beta1
            Package redis is an auto-generated package for the Google Cloud Memorystore for Redis API.
            Package redis is an auto-generated package for the Google Cloud Memorystore for Redis API.
            Package rpcreplay supports the capture and replay of gRPC calls.
            Package rpcreplay supports the capture and replay of gRPC calls.
            proto/intstore
            Package intstore is a generated protocol buffer package.
            Package intstore is a generated protocol buffer package.
            proto/rpcreplay
            Package rpcreplay is a generated protocol buffer package.
            Package rpcreplay is a generated protocol buffer package.
            scheduler
            apiv1beta1
            Package scheduler is an auto-generated package for the Cloud Scheduler API.
            Package scheduler is an auto-generated package for the Cloud Scheduler API.
            securitycenter
            apiv1beta1
            Package securitycenter is an auto-generated package for the Cloud Security Command Center API.
            Package securitycenter is an auto-generated package for the Cloud Security Command Center API.
            Package spanner provides a client for reading and writing to Cloud Spanner databases.
            Package spanner provides a client for reading and writing to Cloud Spanner databases.
            admin/database/apiv1
            Package database is an auto-generated package for the Cloud Spanner Database Admin API.
            Package database is an auto-generated package for the Cloud Spanner Database Admin API.
            admin/instance/apiv1
            Package instance is an auto-generated package for the Cloud Spanner Instance Admin API.
            Package instance is an auto-generated package for the Cloud Spanner Instance Admin API.
            apiv1
            Package spanner is an auto-generated package for the Cloud Spanner API.
            Package spanner is an auto-generated package for the Cloud Spanner API.
            speech
            apiv1
            Converts audio to text by applying powerful neural network models.
            Converts audio to text by applying powerful neural network models.
            apiv1p1beta1
            Package speech is an auto-generated package for the Cloud Speech API.
            Package speech is an auto-generated package for the Cloud Speech API.
            Package storage provides an easy way to work with Google Cloud Storage.
            Package storage provides an easy way to work with Google Cloud Storage.
            texttospeech
            apiv1
            Package texttospeech is an auto-generated package for the Cloud Text-to-Speech API.
            Package texttospeech is an auto-generated package for the Cloud Text-to-Speech API.
            Package trace is OBSOLETE.
            Package trace is OBSOLETE.
            apiv1
            Package trace is an auto-generated package for the Stackdriver Trace API.
            Package trace is an auto-generated package for the Stackdriver Trace API.
            apiv2
            Package trace is an auto-generated package for the Stackdriver Trace API.
            Package trace is an auto-generated package for the Stackdriver Trace API.
            Package translate is a client for the Google Translation API.
            Package translate is a client for the Google Translation API.
            videointelligence
            apiv1
            Package videointelligence is an auto-generated package for the Cloud Video Intelligence API.
            Package videointelligence is an auto-generated package for the Cloud Video Intelligence API.
            apiv1beta1
            Package videointelligence is an auto-generated package for the Google Cloud Video Intelligence API.
            Package videointelligence is an auto-generated package for the Google Cloud Video Intelligence API.
            apiv1beta2
            Package videointelligence is an auto-generated package for the Google Cloud Video Intelligence API.
            Package videointelligence is an auto-generated package for the Google Cloud Video Intelligence API.
            vision
            apiv1
            Integrates Google Vision features, including image labeling, face, logo, and landmark detection, optical character recognition (OCR), and detection of explicit content, into applications.
            Integrates Google Vision features, including image labeling, face, logo, and landmark detection, optical character recognition (OCR), and detection of explicit content, into applications.
            apiv1p1beta1
            Package vision is an auto-generated package for the Google Cloud Vision API.
            Package vision is an auto-generated package for the Google Cloud Vision API.
            btree
            Package btree implements in-memory B-Trees of arbitrary degree.
            Package btree implements in-memory B-Trees of arbitrary degree.
            fields
            Package fields provides a view of the fields of a struct that follows the Go rules, amended to consider tags and case insensitivity.
            Package fields provides a view of the fields of a struct that follows the Go rules, amended to consider tags and case insensitivity.
            leakcheck
            Package leakcheck contains functions to check leaked goroutines.
            Package leakcheck contains functions to check leaked goroutines.
            optional
            Package optional provides versions of primitive types that can be nil.
            Package optional provides versions of primitive types that can be nil.
            pretty
            Package pretty implements a simple pretty-printer.
            Package pretty implements a simple pretty-printer.
            protostruct
            Package protostruct supports operations on the protocol buffer Struct message.
            Package protostruct supports operations on the protocol buffer Struct message.
            testutil
            Package testutil contains helper functions for writing tests.
            Package testutil contains helper functions for writing tests.
            tracecontext
            Package tracecontext provides encoders and decoders for Stackdriver Trace contexts.
            Package tracecontext provides encoders and decoders for Stackdriver Trace contexts.
            uid
            Package uid supports generating unique IDs.
            Package uid supports generating unique IDs.
            version
            Package version contains version information for Google Cloud Client Libraries for Go, as reported in request headers.
            Package version contains version information for Google Cloud Client Libraries for Go, as reported in request headers.