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 2025-03-14 UTC."],[[["The latest release candidate version is 2.37.0-rc, and a range of prior versions are available, starting from version 2.36.0 down to version 2.11.0."],["Version 2.19.0 is used throughout the content as a reference point to demonstrate the functionalities of overriding the authentication configuration."],["You can override the default authentication configuration using `google::cloud::UnifiedCredentialsOption`."],["The example provided demonstrates loading a service account key file, and best practices for managing these keys are available in a separate guide."],["Examples are available for other `*Client` classes such as `DatabaseAdminClient` and `InstanceAdminClient`."]]],[]]