Testing your Cloud BigQueryRead application with googlemock
This document describes how to test your own Cloud BigQueryRead application using the Cloud BigQueryRead C++ client library, Google Test and the Google Test Mocking Framework.
Mocking a Successful BigQueryReadClient::GetServiceAccount() call
First include the headers for the Cloud BigQueryRead Client, the mocking class, and the Google Mock framework:
#include "google/cloud/bigquery/storage/v1/bigquery_read_client.h"
#include "google/cloud/bigquery/storage/v1/mocks/mock_bigquery_read_connection.h"
#include <gmock/gmock.h>
The example uses a number of aliases to save typing and improve readability:
using ::google::cloud::bigquery_storage_v1_mocks::MockBigQueryReadConnection;
namespace bigquery = ::google::cloud::bigquery_storage_v1;
Create a mocking object for google::cloud::bigquery_storage_v1::BigQueryReadConnection
:
auto mock = std::make_shared<MockBigQueryReadConnection>();
It is customary to first setup the expectations for your mock, and then write the rest of the code:
EXPECT_CALL(*mock, CreateReadSession)
.WillOnce([&](google::cloud::bigquery::storage::v1::
CreateReadSessionRequest const& request) {
EXPECT_EQ("test-project-name", request.parent());
EXPECT_EQ("test-table-name", request.read_session().table());
google::cloud::bigquery::storage::v1::ReadSession response;
google::cloud::bigquery::storage::v1::ReadStream stream;
stream.set_name("test-stream");
*response.add_streams() = stream;
return google::cloud::StatusOr<
google::cloud::bigquery::storage::v1::ReadSession>(response);
});
With the expectations in place, create a google::cloud::bigquery_storage_v1::BigQueryReadClient
object:
bigquery::BigQueryReadClient bigquery_client(mock);
And then make calls on the client as usual:
google::cloud::bigquery::storage::v1::ReadSession read_session;
read_session.set_table("test-table-name");
int max_streams = 1;
auto session = bigquery_client.CreateReadSession("test-project-name",
read_session, max_streams);
And then verify the results meet your expectations:
EXPECT_TRUE(session.ok());
EXPECT_EQ("test-stream", session->streams(0).name());
Full Listing
Finally we present the full code for this example:
#include "google/cloud/bigquery/storage/v1/bigquery_read_client.h"
#include "google/cloud/bigquery/storage/v1/mocks/mock_bigquery_read_connection.h"
#include <gmock/gmock.h>
namespace {
using ::google::cloud::bigquery_storage_v1_mocks::MockBigQueryReadConnection;
namespace bigquery = ::google::cloud::bigquery_storage_v1;
TEST(MockCreateReadSessionExample, CreateReadSession) {
auto mock = std::make_shared<MockBigQueryReadConnection>();
EXPECT_CALL(*mock, CreateReadSession)
.WillOnce([&](google::cloud::bigquery::storage::v1::
CreateReadSessionRequest const& request) {
EXPECT_EQ("test-project-name", request.parent());
EXPECT_EQ("test-table-name", request.read_session().table());
google::cloud::bigquery::storage::v1::ReadSession response;
google::cloud::bigquery::storage::v1::ReadStream stream;
stream.set_name("test-stream");
*response.add_streams() = stream;
return google::cloud::StatusOr<
google::cloud::bigquery::storage::v1::ReadSession>(response);
});
bigquery::BigQueryReadClient bigquery_client(mock);
google::cloud::bigquery::storage::v1::ReadSession read_session;
read_session.set_table("test-table-name");
int max_streams = 1;
auto session = bigquery_client.CreateReadSession("test-project-name",
read_session, max_streams);
EXPECT_TRUE(session.ok());
EXPECT_EQ("test-stream", session->streams(0).name());
}
} // namespace