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_IMAGE_ANNOTATOR_ENDPOINT=... overrides the EndpointOption (which defaults to "vision.googleapis.com") used by MakeImageAnnotatorConnection().
GOOGLE_CLOUD_CPP_PRODUCT_SEARCH_ENDPOINT=... overrides the EndpointOption (which defaults to "vision.googleapis.com") used by MakeProductSearchConnection().
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 2025-03-14 UTC."],[[["This document lists the available versions of the C++ Vision library, ranging from version 2.11.0 up to the latest release candidate 2.37.0-rc."],["Environment variables, including `GOOGLE_CLOUD_CPP_IMAGE_ANNOTATOR_ENDPOINT` and `GOOGLE_CLOUD_CPP_PRODUCT_SEARCH_ENDPOINT`, can be used to override default endpoint settings for the library."],["The behavior of gRPC tracing can be modified using `GOOGLE_CLOUD_CPP_TRACING_OPTIONS`, while enabling tracing is achieved with `GOOGLE_CLOUD_CPP_ENABLE_TRACING`."],["Logging within the library can be activated by setting the environment variable `GOOGLE_CLOUD_CPP_ENABLE_CLOG` to \"yes\", allowing output to the program's console."],["`GOOGLE_CLOUD_PROJECT` can be set for examples and integration tests to specify the GCP project, but this variable does not affect the library itself."]]],[]]
