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_APP_HUB_ENDPOINT=... overrides the EndpointOption (which defaults to "apphub.googleapis.com") used by MakeAppHubConnection().
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::LoggingComponentsOptionGOOGLE_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 2025-04-17 UTC."],[[["This page details environment variables and configurations for the App Hub C++ library, with the latest version being 2.37.0-rc."],["The `GOOGLE_CLOUD_CPP_APP_HUB_ENDPOINT` variable overrides the default endpoint used by `MakeAppHubConnection()`, allowing for custom endpoint configurations."],["Tracing of gRPC calls can be enabled via `GOOGLE_CLOUD_CPP_ENABLE_TRACING=rpc`, which, in combination with `GOOGLE_CLOUD_CPP_ENABLE_CLOG`, will output logs to the program's console."],["The environment variable `GOOGLE_CLOUD_CPP_TRACING_OPTIONS` allows users to modify gRPC tracing behavior, including formatting and field truncation."],["Although `GOOGLE_CLOUD_PROJECT` can be used for integration tests and examples, it does not affect library configuration."]]],[]]
