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_STORAGE_TRANSFER_SERVICE_ENDPOINT=... overrides the EndpointOption (which defaults to "storagetransfer.googleapis.com") used by MakeStorageTransferServiceConnection().
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 2025-04-22 UTC."],[[["The latest release candidate version for storage transfer is 2.37.0-rc, with several previous versions available, ranging down to version 2.11.0."],["Environment variables such as `GOOGLE_CLOUD_CPP_STORAGE_TRANSFER_SERVICE_ENDPOINT` can be used to override default settings and customize library behavior, including endpoint configuration."],["Logging for gRPC calls can be enabled via `GOOGLE_CLOUD_CPP_ENABLE_TRACING=rpc`, and the `GOOGLE_CLOUD_CPP_ENABLE_CLOG` environment variable is needed to view the output unless another logging backend is set."],["The `GOOGLE_CLOUD_CPP_TRACING_OPTIONS` variable can be used to change the behavior of gRPC tracing, such as message formatting."],["The variable `GOOGLE_CLOUD_PROJECT` is only used in example and integration testing, and has no effect in the actual library."]]],[]]
