Testing your Cloud IAM Credentials application with googlemock
This document describes how to test your own Cloud IAM application using the Cloud IAM C++ client library, Google Test and the Google Test Mocking Framework.
Mocking a Successful IAMCredentialsClient::SignJwt() call
First include the headers for the Cloud IAM Credentials Client, the mocking class, and the Google Mock framework:
#include "google/cloud/iam/credentials/v1/iam_credentials_client.h"
#include "google/cloud/iam/credentials/v1/mocks/mock_iam_credentials_connection.h"
#include <gmock/gmock.h>
The example uses a number of aliases to save typing and improve readability:
using ::google::cloud::iam_credentials_v1_mocks::MockIAMCredentialsConnection;
namespace iam = ::google::cloud::iam_credentials_v1;
Create a mocking object for google::cloud::iam_credentials_v1::IAMCredentialsConnection
:
auto mock = std::make_shared<MockIAMCredentialsConnection>();
It is customary to first setup the expectations for your mock, and then write the rest of the code:
EXPECT_CALL(*mock, SignJwt)
.WillOnce(
[&](google::iam::credentials::v1::SignJwtRequest const& request) {
EXPECT_EQ("projects/-/serviceAccounts/test-account-unique-id",
request.name());
google::iam::credentials::v1::SignJwtResponse response;
response.set_key_id("test-key-id");
return google::cloud::StatusOr<
google::iam::credentials::v1::SignJwtResponse>(response);
});
With the expectations in place, create a google::cloud::iam_credentials_v1::IAMCredentialsClient
object:
iam::IAMCredentialsClient iam_credentials_client(mock);
And then make calls on the client as usual:
std::string payload;
auto response = iam_credentials_client.SignJwt(
"projects/-/serviceAccounts/test-account-unique-id", {}, payload);
And then verify the results meet your expectations:
EXPECT_TRUE(response.ok());
EXPECT_EQ("test-key-id", response->key_id());
Full Listing
Finally we present the full code for this example:
#include "google/cloud/iam/credentials/v1/iam_credentials_client.h"
#include "google/cloud/iam/credentials/v1/mocks/mock_iam_credentials_connection.h"
#include <gmock/gmock.h>
namespace {
using ::google::cloud::iam_credentials_v1_mocks::MockIAMCredentialsConnection;
namespace iam = ::google::cloud::iam_credentials_v1;
TEST(MockSignJwtExample, SignJwt) {
auto mock = std::make_shared<MockIAMCredentialsConnection>();
EXPECT_CALL(*mock, SignJwt)
.WillOnce(
[&](google::iam::credentials::v1::SignJwtRequest const& request) {
EXPECT_EQ("projects/-/serviceAccounts/test-account-unique-id",
request.name());
google::iam::credentials::v1::SignJwtResponse response;
response.set_key_id("test-key-id");
return google::cloud::StatusOr<
google::iam::credentials::v1::SignJwtResponse>(response);
});
iam::IAMCredentialsClient iam_credentials_client(mock);
std::string payload;
auto response = iam_credentials_client.SignJwt(
"projects/-/serviceAccounts/test-account-unique-id", {}, payload);
EXPECT_TRUE(response.ok());
EXPECT_EQ("test-key-id", response->key_id());
}
} // namespace