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."],[[["This page provides documentation for various versions of the Document AI C++ client library, ranging from version 2.11.0 to 2.37.0-rc, with 2.37.0-rc being the latest release candidate."],["The client libraries generally use Application Default Credentials for authentication with Google Cloud Services, but this can be overridden if necessary."],["You can override the default authentication by providing a `UnifiedCredentialsOption`, as demonstrated in the example code using a service account key file."],["The provided example demonstrates how to explicitly load a service account key file to override the authentication credentials for the Document AI service."],["For comprehensive details on creating `google::cloud::Credentials` objects, refer to the Authentication Components section of the documentation."]]],[]]
