A number of environment variables can be used to configure the behavior of the library. There are also functions to configure this behavior in code. The environment variables are convenient when troubleshooting problems.
Endpoint Overrides
GOOGLE_CLOUD_CPP_IAM_CHECKER_ENDPOINT=... overrides the EndpointOption (which defaults to "policytroubleshooter.googleapis.com") used by MakeIamCheckerConnection().
GOOGLE_CLOUD_CPP_POLICY_TROUBLESHOOTER_ENDPOINT=... overrides the EndpointOption (which defaults to "policytroubleshooter.googleapis.com") used by MakePolicyTroubleshooterConnection().
GOOGLE_CLOUD_CPP_ENABLE_TRACING=rpc: turns on tracing for most gRPC calls. The library injects an additional Stub decorator that prints each gRPC request and response. Unless you have configured your own logging backend, you should also set GOOGLE_CLOUD_CPP_ENABLE_CLOG to produce any output on the program's console.
See Also
google::cloud::LoggingComponentsOptionGOOGLE_CLOUD_CPP_TRACING_OPTIONS=...: modifies the behavior of gRPC tracing, including whether messages will be output on multiple lines, or whether string/bytes fields will be truncated.
See Also
google::cloud::GrpcTracingOptionsOptionGOOGLE_CLOUD_CPP_ENABLE_CLOG=yes: turns on logging in the library, basically the library always "logs" but the logging infrastructure has no backend to actually print anything until the application sets a backend or they set this environment variable.
[[["Easy to understand","easyToUnderstand","thumb-up"],["Solved my problem","solvedMyProblem","thumb-up"],["Other","otherUp","thumb-up"]],[["Missing the information I need","missingTheInformationINeed","thumb-down"],["Too complicated / too many steps","tooComplicatedTooManySteps","thumb-down"],["Out of date","outOfDate","thumb-down"],["Samples / code issue","samplesCodeIssue","thumb-down"],["Other","otherDown","thumb-down"]],["Last updated 2025-08-14 UTC."],[[["\u003cp\u003eThis document lists available versions of the Policy Troubleshooter, ranging from version 2.11.0 to the latest release candidate 2.37.0-rc, with direct links to each version's documentation.\u003c/p\u003e\n"],["\u003cp\u003eEnvironment variables such as \u003ccode\u003eGOOGLE_CLOUD_CPP_IAM_CHECKER_ENDPOINT\u003c/code\u003e and \u003ccode\u003eGOOGLE_CLOUD_CPP_POLICY_TROUBLESHOOTER_ENDPOINT\u003c/code\u003e can be used to override the default endpoints for IAM Checker and Policy Troubleshooter connections, respectively.\u003c/p\u003e\n"],["\u003cp\u003eTracing and logging for gRPC calls can be enabled using \u003ccode\u003eGOOGLE_CLOUD_CPP_ENABLE_TRACING\u003c/code\u003e and \u003ccode\u003eGOOGLE_CLOUD_CPP_ENABLE_CLOG\u003c/code\u003e, with further customization options available through \u003ccode\u003eGOOGLE_CLOUD_CPP_TRACING_OPTIONS\u003c/code\u003e.\u003c/p\u003e\n"],["\u003cp\u003eThe environment variable \u003ccode\u003eGOOGLE_CLOUD_PROJECT\u003c/code\u003e is utilized in examples and integration tests for project configuration but does not impact the core functionality of the library.\u003c/p\u003e\n"]]],[],null,[]]
