Unless otherwise configured, the client libraries useApplication Default Credentialsto authenticate with Google Cloud Services. While this works for most applications, in some cases you may need to override this default. You can do so by providing theUnifiedCredentialsOptionThe following example shows how to explicitly load a service account key file:
[](std::string const& keyfile) {
auto is = std::ifstream(keyfile);
is.exceptions(std::ios::badbit); // Minimal error handling in examples
auto contents = std::string(std::istreambuf_iterator<char>(is.rdbuf()), {});
auto options =
google::cloud::Options{}.set<google::cloud::UnifiedCredentialsOption>(
google::cloud::MakeServiceAccountCredentials(contents));
return google::cloud::redis_cluster_v1::CloudRedisClusterClient(
google::cloud::redis_cluster_v1::MakeCloudRedisClusterConnection(
options));
}
Follow these links to find examples for other*Clientclasses:
[[["Easy to understand","easyToUnderstand","thumb-up"],["Solved my problem","solvedMyProblem","thumb-up"],["Other","otherUp","thumb-up"]],[["Hard to understand","hardToUnderstand","thumb-down"],["Incorrect information or sample code","incorrectInformationOrSampleCode","thumb-down"],["Missing the information/samples I need","missingTheInformationSamplesINeed","thumb-down"],["Other","otherDown","thumb-down"]],["Last updated 2025-09-04 UTC."],[[["\u003cp\u003eThis document provides a guide on how to override default authentication credentials when using Google Cloud client libraries, focusing on Redis.\u003c/p\u003e\n"],["\u003cp\u003eThe client libraries typically use Application Default Credentials (ADC), but users can override this by using the \u003ccode\u003eUnifiedCredentialsOption\u003c/code\u003e.\u003c/p\u003e\n"],["\u003cp\u003eThe document gives an example showing how to load a service account key file explicitly, overriding the default credentials.\u003c/p\u003e\n"],["\u003cp\u003eVersion history of this document from \u003ccode\u003e2.11.0\u003c/code\u003e to \u003ccode\u003e2.37.0-rc\u003c/code\u003e can be found in the list provided, with \u003ccode\u003e2.37.0-rc\u003c/code\u003e being the latest.\u003c/p\u003e\n"],["\u003cp\u003eLinks to code examples for \u003ccode\u003eredis_cluster_v1::CloudRedisClusterClient\u003c/code\u003e and \u003ccode\u003eredis_v1::CloudRedisClient\u003c/code\u003e are available, allowing you to view client specific implementations.\u003c/p\u003e\n"]]],[],null,["Version 2.24.0keyboard_arrow_down\n\n- [2.42.0-rc (latest)](/cpp/docs/reference/redis/latest/redis-override-authentication)\n- [2.41.0](/cpp/docs/reference/redis/2.41.0/redis-override-authentication)\n- [2.40.0](/cpp/docs/reference/redis/2.40.0/redis-override-authentication)\n- [2.39.0](/cpp/docs/reference/redis/2.39.0/redis-override-authentication)\n- [2.38.0](/cpp/docs/reference/redis/2.38.0/redis-override-authentication)\n- [2.37.0](/cpp/docs/reference/redis/2.37.0/redis-override-authentication)\n- [2.36.0](/cpp/docs/reference/redis/2.36.0/redis-override-authentication)\n- [2.35.0](/cpp/docs/reference/redis/2.35.0/redis-override-authentication)\n- [2.34.0](/cpp/docs/reference/redis/2.34.0/redis-override-authentication)\n- [2.33.0](/cpp/docs/reference/redis/2.33.0/redis-override-authentication)\n- [2.32.0](/cpp/docs/reference/redis/2.32.0/redis-override-authentication)\n- [2.31.0](/cpp/docs/reference/redis/2.31.0/redis-override-authentication)\n- [2.30.0](/cpp/docs/reference/redis/2.30.0/redis-override-authentication)\n- [2.29.0](/cpp/docs/reference/redis/2.29.0/redis-override-authentication)\n- [2.28.0](/cpp/docs/reference/redis/2.28.0/redis-override-authentication)\n- [2.27.0](/cpp/docs/reference/redis/2.27.0/redis-override-authentication)\n- [2.26.0](/cpp/docs/reference/redis/2.26.0/redis-override-authentication)\n- [2.25.1](/cpp/docs/reference/redis/2.25.1/redis-override-authentication)\n- [2.24.0](/cpp/docs/reference/redis/2.24.0/redis-override-authentication)\n- [2.23.0](/cpp/docs/reference/redis/2.23.0/redis-override-authentication)\n- [2.22.1](/cpp/docs/reference/redis/2.22.1/redis-override-authentication)\n- [2.21.0](/cpp/docs/reference/redis/2.21.0/redis-override-authentication)\n- [2.20.0](/cpp/docs/reference/redis/2.20.0/redis-override-authentication)\n- [2.19.0](/cpp/docs/reference/redis/2.19.0/redis-override-authentication)\n- [2.18.0](/cpp/docs/reference/redis/2.18.0/redis-override-authentication)\n- [2.17.0](/cpp/docs/reference/redis/2.17.0/redis-override-authentication)\n- [2.16.0](/cpp/docs/reference/redis/2.16.0/redis-override-authentication)\n- [2.15.1](/cpp/docs/reference/redis/2.15.1/redis-override-authentication)\n- [2.14.0](/cpp/docs/reference/redis/2.14.0/redis-override-authentication)\n- [2.13.0](/cpp/docs/reference/redis/2.13.0/redis-override-authentication)\n- [2.12.0](/cpp/docs/reference/redis/2.12.0/redis-override-authentication)\n- [2.11.0](/cpp/docs/reference/redis/2.11.0/redis-override-authentication) \n\nHow to Override the Authentication Credentials\n==============================================\n\nUnless otherwise configured, the client libraries use [Application Default Credentials](https://cloud.google.com/docs/authentication#adc) to authenticate with Google Cloud Services. While this works for most applications, in some cases you may need to override this default. You can do so by providing the [UnifiedCredentialsOption](https://cloud.google.com/cpp/docs/reference/common/latest/structgoogle_1_1cloud_1_1UnifiedCredentialsOption.html) The following example shows how to explicitly load a service account key file: \n\n [](std::string const& keyfile) {\n auto is = std::ifstream(keyfile);\n is.exceptions(std::ios::badbit); // Minimal error handling in examples\n auto contents = std::string(std::istreambuf_iterator\u003cchar\u003e(is.rdbuf()), {});\n auto options =\n google::cloud::Options{}.set\u003cgoogle::cloud::UnifiedCredentialsOption\u003e(\n google::cloud::MakeServiceAccountCredentials(contents));\n return google::cloud::redis_cluster_v1::CloudRedisClusterClient(\n google::cloud::redis_cluster_v1::MakeCloudRedisClusterConnection(\n options));\n }\n\nFollow these links to find examples for other `*Client` classes:\n\n- [`redis_cluster_v1::CloudRedisClusterClient`](/cpp/docs/reference/redis/2.24.0/redis_cluster_v1_1_1CloudRedisClusterClient-service-account-snippet)\n- [`redis_v1::CloudRedisClient`](/cpp/docs/reference/redis/2.24.0/redis_v1_1_1CloudRedisClient-service-account-snippet)\n\nKeep in mind that we chose this as an example because it is relatively easy to understand. Consult the [Best practices for managing service account keys](https://cloud.google.com/iam/docs/best-practices-for-managing-service-account-keys) guide for more details.\n\n###### See Also\n\n[Authentication Components](https://cloud.google.com/cpp/docs/reference/common/latest/group__guac.html) - for more information on the factory functions to create [`google::cloud::Credentials`](https://cloud.google.com/cpp/docs/reference/common/latest/classgoogle_1_1cloud_1_1Credentials.html) objects."]]