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_ENVIRONMENTS_ENDPOINT=... overrides the EndpointOption (which defaults to "composer.googleapis.com") used by MakeEnvironmentsConnection().
GOOGLE_CLOUD_CPP_IMAGE_VERSIONS_ENDPOINT=... overrides the EndpointOption (which defaults to "composer.googleapis.com") used by MakeImageVersionsConnection().
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 2025-03-05 UTC."],[[["This document provides a comprehensive list of available versions, ranging from 2.11.0 to the release candidate 2.37.0-rc, for the C++ Composer library."],["The C++ Composer library's behavior can be configured using several environment variables, offering flexibility in troubleshooting and customization."],["Endpoint overrides can be set using `GOOGLE_CLOUD_CPP_ENVIRONMENTS_ENDPOINT` and `GOOGLE_CLOUD_CPP_IMAGE_VERSIONS_ENDPOINT` to modify the default endpoints for specific connections."],["Logging and tracing can be enabled and customized via environment variables like `GOOGLE_CLOUD_CPP_ENABLE_TRACING`, `GOOGLE_CLOUD_CPP_TRACING_OPTIONS`, and `GOOGLE_CLOUD_CPP_ENABLE_CLOG`."],["The `GOOGLE_CLOUD_PROJECT` environment variable can be used in examples and tests to set the GCP project but it does not have any effect in the library itself."]]],[]]
