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_AGENT_ENDPOINT_SERVICE_ENDPOINT=... overrides the EndpointOption (which defaults to "osconfig.googleapis.com") used by MakeAgentEndpointServiceConnection().
GOOGLE_CLOUD_CPP_OS_CONFIG_SERVICE_ENDPOINT=... overrides the EndpointOption (which defaults to "osconfig.googleapis.com") used by MakeOsConfigServiceConnection().
GOOGLE_CLOUD_CPP_OS_CONFIG_ZONAL_SERVICE_ENDPOINT=... overrides the EndpointOption (which defaults to "osconfig.googleapis.com") used by MakeOsConfigZonalServiceConnection().
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"]],[["Hard to understand","hardToUnderstand","thumb-down"],["Incorrect information or sample code","incorrectInformationOrSampleCode","thumb-down"],["Missing the information/samples I need","missingTheInformationSamplesINeed","thumb-down"],["Other","otherDown","thumb-down"]],["Last updated 2025-04-23 UTC."],[[["The latest release candidate version is 2.37.0-rc, and numerous previous versions are available, ranging down to version 2.11.0 for the osconfig environment."],["Several environment variables can be used to configure the library's behavior, particularly useful for troubleshooting, and there are also corresponding in-code configuration functions."],["Specific environment variables such as `GOOGLE_CLOUD_CPP_AGENT_ENDPOINT_SERVICE_ENDPOINT`, `GOOGLE_CLOUD_CPP_OS_CONFIG_SERVICE_ENDPOINT`, and `GOOGLE_CLOUD_CPP_OS_CONFIG_ZONAL_SERVICE_ENDPOINT` allow overriding the default endpoint options."],["Tracing and logging for gRPC calls can be enabled and configured using environment variables like `GOOGLE_CLOUD_CPP_ENABLE_TRACING`, `GOOGLE_CLOUD_CPP_TRACING_OPTIONS`, and `GOOGLE_CLOUD_CPP_ENABLE_CLOG`."],["While the `GOOGLE_CLOUD_PROJECT` environment variable is used in examples and tests to configure the GCP project, it does not affect the behavior of the library itself."]]],[]]
