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_SERVICE_HEALTH_ENDPOINT=... overrides the EndpointOption (which defaults to "servicehealth.googleapis.com") used by MakeServiceHealthConnection().
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complicated / too many steps","tooComplicatedTooManySteps","thumb-down"],["Out of date","outOfDate","thumb-down"],["Samples / code issue","samplesCodeIssue","thumb-down"],["Other","otherDown","thumb-down"]],["Last updated 2025-08-14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\u003eThe latest release candidate version is 2.37.0-rc, and the page provides documentation links for versions ranging from 2.21.0 up to 2.36.0.\u003c/p\u003e\n"],["\u003cp\u003eEnvironment variables like \u003ccode\u003eGOOGLE_CLOUD_CPP_SERVICE_HEALTH_ENDPOINT\u003c/code\u003e can be used to customize library behavior, such as overriding the default endpoint used by \u003ccode\u003eMakeServiceHealthConnection()\u003c/code\u003e.\u003c/p\u003e\n"],["\u003cp\u003eTracing for gRPC calls can be enabled by setting \u003ccode\u003eGOOGLE_CLOUD_CPP_ENABLE_TRACING=rpc\u003c/code\u003e, and output to the console requires \u003ccode\u003eGOOGLE_CLOUD_CPP_ENABLE_CLOG\u003c/code\u003e to also be set.\u003c/p\u003e\n"],["\u003cp\u003eThe variable \u003ccode\u003eGOOGLE_CLOUD_CPP_TRACING_OPTIONS\u003c/code\u003e controls the behavior of gRPC tracing, affecting output formatting, while \u003ccode\u003eGOOGLE_CLOUD_CPP_ENABLE_CLOG=yes\u003c/code\u003e enables logging in the library.\u003c/p\u003e\n"],["\u003cp\u003e\u003ccode\u003eGOOGLE_CLOUD_PROJECT\u003c/code\u003e can be used for examples and integration testing, however it will not have any effect in the library.\u003c/p\u003e\n"]]],[],null,[]]