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_ACCESS_CONTEXT_MANAGER_ENDPOINT=... overrides the EndpointOption (which defaults to "accesscontextmanager.googleapis.com") used by MakeAccessContextManagerConnection().
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"]],[["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complicated / too many steps","tooComplicatedTooManySteps","thumb-down"],["Out of date","outOfDate","thumb-down"],["Samples / code issue","samplesCodeIssue","thumb-down"],["Other","otherDown","thumb-down"]],["Last updated 2025-07-09 UTC."],[[["This document provides version-specific documentation for the Access Context Manager, with the latest release candidate being version 2.37.0-rc."],["The content includes a comprehensive list of previous versions, starting from 2.36.0 down to 2.11.0, each with a corresponding link."],["Environment variables, such as `GOOGLE_CLOUD_CPP_ACCESS_CONTEXT_MANAGER_ENDPOINT`, can be used to configure library behavior, such as overriding the default endpoint."],["Logging and tracing for gRPC calls can be enabled and customized using environment variables like `GOOGLE_CLOUD_CPP_ENABLE_TRACING` and `GOOGLE_CLOUD_CPP_TRACING_OPTIONS`."],["The `GOOGLE_CLOUD_PROJECT` is used for examples and tests to set the GCP project, but it does not modify the library itself."]]],[]]