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_IAM_CREDENTIALS_ENDPOINT=... overrides the EndpointOption (which defaults to "iamcredentials.googleapis.com") used by MakeIAMCredentialsConnection().
GOOGLE_CLOUD_CPP_IAM_ENDPOINT=... overrides the EndpointOption (which defaults to "iam.googleapis.com") used by MakeIAMConnection().
GOOGLE_CLOUD_CPP_IAM_POLICY_ENDPOINT=... overrides the EndpointOption (which defaults to "iam-meta-api.googleapis.com") used by MakeIAMPolicyConnection().
GOOGLE_CLOUD_CPP_POLICIES_ENDPOINT=... overrides the EndpointOption (which defaults to "iam.googleapis.com") used by MakePoliciesConnection().
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 2025-04-09 UTC."],[[["This document provides reference information for different versions of the IAM (Identity and Access Management) C++ library, with the latest release candidate being 2.37.0-rc."],["Environment variables can be used to configure the IAM C++ library's behavior, providing a convenient method for troubleshooting."],["Specific endpoint override environment variables allow users to change the default endpoints used by different IAM connection functions, such as `GOOGLE_CLOUD_CPP_IAM_CREDENTIALS_ENDPOINT`, `GOOGLE_CLOUD_CPP_IAM_ENDPOINT`, `GOOGLE_CLOUD_CPP_IAM_POLICY_ENDPOINT`, and `GOOGLE_CLOUD_CPP_POLICIES_ENDPOINT`."],["Tracing for gRPC calls can be enabled by setting `GOOGLE_CLOUD_CPP_ENABLE_TRACING=rpc`, and logging within the library can be activated by setting `GOOGLE_CLOUD_CPP_ENABLE_CLOG=yes`, allowing for detailed debugging and monitoring."],["The environment variable `GOOGLE_CLOUD_PROJECT` can be used to configure the GCP project, but only for the use of the examples and integration tests, as it does not have any effect on the library itself."]]],[]]