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_LOGGING_SERVICE_V2_ENDPOINT=... overrides the EndpointOption (which defaults to "logging.googleapis.com") used by MakeLoggingServiceV2Connection().
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complicated / too many steps","tooComplicatedTooManySteps","thumb-down"],["Out of date","outOfDate","thumb-down"],["Samples / code issue","samplesCodeIssue","thumb-down"],["Other","otherDown","thumb-down"]],["Last updated 2025-08-14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 environment variable configurations for the C++ logging library, specifically for versions ranging from 2.11.0 to 2.37.0-rc, with the latest being 2.37.0-rc.\u003c/p\u003e\n"],["\u003cp\u003eEnvironment variables can be used to modify the library's behavior, particularly useful when troubleshooting, such as \u003ccode\u003eGOOGLE_CLOUD_CPP_LOGGING_SERVICE_V2_ENDPOINT\u003c/code\u003e to override the default endpoint.\u003c/p\u003e\n"],["\u003cp\u003eTracing can be enabled for gRPC calls using \u003ccode\u003eGOOGLE_CLOUD_CPP_ENABLE_TRACING=rpc\u003c/code\u003e, and output can be directed to the console with \u003ccode\u003eGOOGLE_CLOUD_CPP_ENABLE_CLOG\u003c/code\u003e, which also allows customization via \u003ccode\u003eGOOGLE_CLOUD_CPP_TRACING_OPTIONS\u003c/code\u003e.\u003c/p\u003e\n"],["\u003cp\u003eWhile \u003ccode\u003eGOOGLE_CLOUD_PROJECT\u003c/code\u003e is used in examples and integration tests to configure the GCP project, it does not have an effect on the library itself.\u003c/p\u003e\n"]]],[],null,[]]
