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 webpage documents the environment variables for configuring the behavior of the OS Config C++ client library, alongside links to the documentation for each version."],["Users can override default endpoints for `AgentEndpointServiceConnection`, `OsConfigServiceConnection`, and `OsConfigZonalServiceConnection` using environment variables like `GOOGLE_CLOUD_CPP_AGENT_ENDPOINT_SERVICE_ENDPOINT`."],["The `GOOGLE_CLOUD_CPP_ENABLE_TRACING=rpc` variable activates tracing for gRPC calls, while `GOOGLE_CLOUD_CPP_ENABLE_CLOG=yes` turns on logging within the library, directing output to the console if no other logging backend is configured."],["The environment variable `GOOGLE_CLOUD_PROJECT` sets the default project and is used for examples and testing, however, it has no effect in the library."],["The most recent release candidate for this documentation is version 2.37.0-rc, followed by versions ranging from 2.36.0 to 2.11.0."]]],[]]
