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_SIMULATOR_ENDPOINT=... overrides the EndpointOption (which defaults to "policysimulator.googleapis.com") used by MakeSimulatorConnection().
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::TracingComponentsOptionGOOGLE_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complicated / too many steps","tooComplicatedTooManySteps","thumb-down"],["Out of date","outOfDate","thumb-down"],["Samples / code issue","samplesCodeIssue","thumb-down"],["Other","otherDown","thumb-down"]],["Last updated 2025-08-14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 provides versioned documentation for the Policy Simulator environment, with the latest release candidate being version 2.37.0-rc.\u003c/p\u003e\n"],["\u003cp\u003eThe content lists available versions, ranging from the latest (2.37.0-rc) down to 2.15.1, each with a corresponding link to their respective documentation.\u003c/p\u003e\n"],["\u003cp\u003eEnvironment variables like \u003ccode\u003eGOOGLE_CLOUD_CPP_SIMULATOR_ENDPOINT\u003c/code\u003e can override default endpoints and others like \u003ccode\u003eGOOGLE_CLOUD_CPP_ENABLE_TRACING\u003c/code\u003e, \u003ccode\u003eGOOGLE_CLOUD_CPP_TRACING_OPTIONS\u003c/code\u003e, and \u003ccode\u003eGOOGLE_CLOUD_CPP_ENABLE_CLOG\u003c/code\u003e can be used to enable and configure tracing and logging.\u003c/p\u003e\n"],["\u003cp\u003eThe variable \u003ccode\u003eGOOGLE_CLOUD_PROJECT\u003c/code\u003e can be used in integration tests to configure the project but has no effect in the library.\u003c/p\u003e\n"]]],[],null,[]]
