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_CONFIG_SERVICE_V2_ENDPOINT=... overrides the EndpointOption (which defaults to "logging.googleapis.com") used by MakeConfigServiceV2Connection().
GOOGLE_CLOUD_CPP_LOGGING_SERVICE_V2_ENDPOINT=... overrides the EndpointOption (which defaults to "logging.googleapis.com") used by MakeLoggingServiceV2Connection().
GOOGLE_CLOUD_CPP_METRICS_SERVICE_V2_ENDPOINT=... overrides the EndpointOption (which defaults to "logging.googleapis.com") used by MakeMetricsServiceV2Connection().
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complicated / too many steps","tooComplicatedTooManySteps","thumb-down"],["Out of date","outOfDate","thumb-down"],["Samples / code issue","samplesCodeIssue","thumb-down"],["Other","otherDown","thumb-down"]],["Last updated 2025-08-14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 page provides documentation for configuring the behavior of the logging library using environment variables, including various versions with version \u003ccode\u003e2.37.0-rc\u003c/code\u003e as the latest.\u003c/p\u003e\n"],["\u003cp\u003eEnvironment variables can be used for configuring logging behavior, such as \u003ccode\u003eGOOGLE_CLOUD_CPP_ENABLE_TRACING\u003c/code\u003e to enable tracing for gRPC calls and \u003ccode\u003eGOOGLE_CLOUD_CPP_ENABLE_CLOG\u003c/code\u003e to activate logging output.\u003c/p\u003e\n"],["\u003cp\u003eThe behavior of the \u003ccode\u003eEndpointOption\u003c/code\u003e for service connections can be overridden using environment variables like \u003ccode\u003eGOOGLE_CLOUD_CPP_CONFIG_SERVICE_V2_ENDPOINT\u003c/code\u003e, \u003ccode\u003eGOOGLE_CLOUD_CPP_LOGGING_SERVICE_V2_ENDPOINT\u003c/code\u003e, and \u003ccode\u003eGOOGLE_CLOUD_CPP_METRICS_SERVICE_V2_ENDPOINT\u003c/code\u003e.\u003c/p\u003e\n"],["\u003cp\u003eThe \u003ccode\u003eGOOGLE_CLOUD_CPP_TRACING_OPTIONS\u003c/code\u003e environment variable allows the modification of gRPC tracing behavior, such as multiline output or string truncation.\u003c/p\u003e\n"],["\u003cp\u003eThe \u003ccode\u003eGOOGLE_CLOUD_PROJECT\u003c/code\u003e environment variable is utilized in examples and integration tests to set the GCP project but does not affect the library's functionality directly.\u003c/p\u003e\n"]]],[],null,[]]
