namespace spanner = ::google::cloud::spanner;
[](std::string const& project_id, std::string const& instance_id,
std::string const& database_id, std::string const& keyfile) {
auto is = std::ifstream(keyfile);
is.exceptions(std::ios::badbit);
auto contents = std::string(std::istreambuf_iterator<char>(is.rdbuf()), {});
auto options =
google::cloud::Options{}.set<google::cloud::UnifiedCredentialsOption>(
google::cloud::MakeServiceAccountCredentials(contents));
return spanner::Client(spanner::MakeConnection(
spanner::Database(project_id, instance_id, database_id), options));
}
Keep 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] guide for more details.
Follow these links to find examples for other *Client classes:
[[["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 2025-03-21 UTC."],[[["This page provides access to documentation for various versions of the Spanner C++ client library, ranging from version 2.11.0 up to the latest release candidate, 2.37.0-rc."],["The primary focus of the content is demonstrating how to override the default authentication configuration for Spanner client connections, using `google::cloud::UnifiedCredentialsOption`."],["An example is provided showing how to explicitly load a service account key file for authentication, including a code snippet."],["The documentation suggests consulting the \"Best practices for managing service account keys\" guide for more comprehensive information on handling service account credentials."],["Links to examples for other client classes, specifically `DatabaseAdminClient` and `InstanceAdminClient`, are provided for version 2.21.0, showing how to use service accounts."]]],[]]