spanner: refactor mockclient

This CL refactors MockCloudSpannerClient, removing the Actions
expectations/return value setup slice, the nice bool (fail all requests), and
the injErr map (fail specific request). These are replaced by a simpler
ReceivedRequests channel that users can assert on to introspect requests sent
to the stub, as well as a simple function-injectable wrapper to perform
test-specific overloading of methods for things like errors.

This CL is in preparation for a future unit test that asserts on the contents
of a request (which we can now introspect using ReceivedRequests). This CL
also attempts to make these tests more readable, by moving assertions and
custom response logic directly into the test instead of having to figure
out how different methods in the mock behave.

This CL also does a large amount of general clean-up:

- setup and mockClient merged into a single function, serverClientMock, that
inits the client and the mock. Also, consolidate all test cleanup into a
callback, and make sure the callback gets called everywhere.
- TestReadOnlyAcquire split into several tests.
- Amazingly integration_test.go's TestMain was causing -short to skip ALL
tests. Its preconditions have been split into a new function
initIntegrationTest to prevent this, causing -short to once again work as
- prepare renamed prepareIntegrationTest.
- All integration tests renamed to TestIntegration_*.
- Moved TestStructParametersBind to integration_test.go, renamed
- Moved test-specific variables like errAbrt from global scope to the one
test that uses them.
- Call and assign context.Background once instead of re-calling it everywhere
that context is expected.
- Convert to using Fatalf instead of Errorf. This is slightly overkill: Errorf
should be preferred. However, these tests tend to snowball fail such that the
first failure causes all subsequent assertions to fail. In the future we might
want to revisit this and look more closely.
- Re-write several test descriptions to be understandable and clear.
- Re-write several test names to be more indicative of what's being tested.
- Re-write several test assertions to use better failure descriptions, as well
as %+v.
- Removed several testing.Short->t.Skip statements from unit tests (should
only be on integration tests and the like).

Change-Id: I100319acad62db08da1f168bf5087bdfccd3b6b2
Reviewed-by: kokoro <>
Reviewed-by: Eno Compton <>
9 files changed
tree: 80febc918a41f3d59fa19d9ef0c3d8d93b2363b1
  9. asset/
  10. authexample_test.go
  11. bigquery/
  12. bigtable/
  13. civil/
  14. cloud.go
  15. cloudtasks/
  16. cmd/
  17. compute/
  18. container/
  19. containeranalysis/
  20. dataproc/
  21. datastore/
  22. debugger/
  23. dialogflow/
  24. dlp/
  25. errorreporting/
  26. examples_test.go
  27. expr/
  28. firestore/
  29. functions/
  30. httpreplay/
  31. iam/
  32. internal/
  34. keys.tar.enc
  35. kms/
  36. language/
  37. license_test.go
  38. logging/
  39. longrunning/
  40. monitoring/
  42. oslogin/
  43. profiler/
  44. pubsub/
  45. redis/
  47. rpcreplay/
  49. scheduler/
  50. securitycenter/
  51. spanner/
  52. speech/
  53. storage/
  54. texttospeech/
  55. trace/
  56. translate/
  57. videointelligence/
  58. vision/

Google Cloud Client Libraries for Go


Go packages for Google Cloud Platform services.

import ""

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

$ go get -u

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

NOTE: Github repo is a mirror of


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 APIStatusPackage
Data Loss
Text To

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

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.


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 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 {

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 {

Cloud Storage GoDoc

Example Usage

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

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

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 {

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 {

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

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 {
	if err != nil {
		// TODO: Handle error.

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 {
// Simple Reads And Writes
_, err = client.Apply(ctx, []*spanner.Mutation{
		[]string{"name", "email"},
		[]interface{}{"alice", ""})})
if err != nil {
row, err := client.Single().ReadRow(ctx, "Users",
	spanner.Key{"alice"}, []string{"email"})
if err != nil {


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.