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 2025-03-21 UTC."],[[["This document provides a comprehensive list of C++ Composer versions, ranging from the latest release candidate (2.37.0-rc) down to version 2.11.0, with each version linking to its respective documentation."],["Environment variables can be utilized to modify the behavior of the library, especially useful during the process of troubleshooting issues."],["Specific environment variables, `GOOGLE_CLOUD_CPP_ENVIRONMENTS_ENDPOINT` and `GOOGLE_CLOUD_CPP_IMAGE_VERSIONS_ENDPOINT`, allow users to override default endpoints for Environments and Image Versions connections, respectively."],["Tracing for gRPC calls can be enabled using `GOOGLE_CLOUD_CPP_ENABLE_TRACING=rpc`, and the `GOOGLE_CLOUD_CPP_TRACING_OPTIONS` environment variable can further refine the behavior of this tracing."],["Enabling logging in the library can be done by setting `GOOGLE_CLOUD_CPP_ENABLE_CLOG=yes` which allows the application to output logs to the console."]]],[]]
