Unless otherwise configured, the client libraries use Application Default Credentials 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 The 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::documentai_v1::DocumentProcessorServiceClient(
google::cloud::documentai_v1::MakeDocumentProcessorServiceConnection(
options));
}
[[["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 webpage provides documentation for various versions of the Document AI C++ client library, ranging from version 2.11.0 to 2.37.0-rc, with links to each version's documentation."],["The latest release candidate version of the Document AI C++ client library is 2.37.0-rc."],["The client libraries primarily utilize Application Default Credentials for authentication with Google Cloud Services, but offer methods to override these defaults."],["Overriding default credentials can be achieved using `UnifiedCredentialsOption`, such as by explicitly loading a service account key file, as demonstrated in the example code."],["Users can find additional information on authentication components and managing service account keys by following the provided links to Authentication Components and the Best practices for managing service account keys."]]],[]]
