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::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 2025-03-14 UTC."],[[["This document outlines environment variables and configurations for the C++ Vision library, detailing how to control its behavior through both environment settings and in-code functions."],["The document lists available versions of the C++ Vision library, from version 2.11.0 up to the latest release candidate 2.37.0-rc, with direct links to each version's documentation."],["Environment variables such as `GOOGLE_CLOUD_CPP_IMAGE_ANNOTATOR_ENDPOINT` and `GOOGLE_CLOUD_CPP_PRODUCT_SEARCH_ENDPOINT` allow users to override default endpoints for specific components like image annotation and product search, respectively."],["Logging and tracing functionalities can be managed using variables like `GOOGLE_CLOUD_CPP_ENABLE_TRACING`, `GOOGLE_CLOUD_CPP_TRACING_OPTIONS`, and `GOOGLE_CLOUD_CPP_ENABLE_CLOG`, enabling detailed monitoring and troubleshooting."],["`GOOGLE_CLOUD_PROJECT` is an environment variable that can be used to configure the GCP project, but only applies to examples and integration tests, not directly the library itself."]]],[]]
