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_ANALYTICS_SERVICE_ENDPOINT=...overrides theEndpointOption(which defaults to "retail.googleapis.com") used byMakeAnalyticsServiceConnection().
GOOGLE_CLOUD_CPP_CATALOG_SERVICE_ENDPOINT=...overrides theEndpointOption(which defaults to "retail.googleapis.com") used byMakeCatalogServiceConnection().
GOOGLE_CLOUD_CPP_COMPLETION_SERVICE_ENDPOINT=...overrides theEndpointOption(which defaults to "retail.googleapis.com") used byMakeCompletionServiceConnection().
GOOGLE_CLOUD_CPP_CONTROL_SERVICE_ENDPOINT=...overrides theEndpointOption(which defaults to "retail.googleapis.com") used byMakeControlServiceConnection().
GOOGLE_CLOUD_CPP_MODEL_SERVICE_ENDPOINT=...overrides theEndpointOption(which defaults to "retail.googleapis.com") used byMakeModelServiceConnection().
GOOGLE_CLOUD_CPP_PRODUCT_SERVICE_ENDPOINT=...overrides theEndpointOption(which defaults to "retail.googleapis.com") used byMakeProductServiceConnection().
GOOGLE_CLOUD_CPP_RETAIL_PREDICTION_SERVICE_ENDPOINT=...overrides theEndpointOption(which defaults to "retail.googleapis.com") used byMakePredictionServiceConnection().
GOOGLE_CLOUD_CPP_SEARCH_SERVICE_ENDPOINT=...overrides theEndpointOption(which defaults to "retail.googleapis.com") used byMakeSearchServiceConnection().
GOOGLE_CLOUD_CPP_SERVING_CONFIG_SERVICE_ENDPOINT=...overrides theEndpointOption(which defaults to "retail.googleapis.com") used byMakeServingConfigServiceConnection().
GOOGLE_CLOUD_CPP_USER_EVENT_SERVICE_ENDPOINT=...overrides theEndpointOption(which defaults to "retail.googleapis.com") used byMakeUserEventServiceConnection().
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 setGOOGLE_CLOUD_CPP_ENABLE_CLOGto 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 2025-09-04 UTC."],[[["\u003cp\u003eThis document provides reference information for various versions of the C++ Retail library, ranging from version 2.11.0 up to the latest release candidate, 2.37.0-rc.\u003c/p\u003e\n"],["\u003cp\u003eThe library's behavior can be configured using environment variables, offering a convenient way to troubleshoot issues without modifying code directly, and there are also functions to configure behavior in the code itself.\u003c/p\u003e\n"],["\u003cp\u003eEndpoint overrides are available for different services like Analytics, Catalog, Completion, and more, by using environment variables that begin with \u003ccode\u003eGOOGLE_CLOUD_CPP\u003c/code\u003e, allowing for customization of the default "retail.googleapis.com" endpoint.\u003c/p\u003e\n"],["\u003cp\u003eTracing and logging can be enabled and customized using environment variables such as \u003ccode\u003eGOOGLE_CLOUD_CPP_ENABLE_TRACING\u003c/code\u003e, \u003ccode\u003eGOOGLE_CLOUD_CPP_TRACING_OPTIONS\u003c/code\u003e, and \u003ccode\u003eGOOGLE_CLOUD_CPP_ENABLE_CLOG\u003c/code\u003e, which help in monitoring gRPC calls and application behavior.\u003c/p\u003e\n"],["\u003cp\u003eAlthough \u003ccode\u003eGOOGLE_CLOUD_PROJECT\u003c/code\u003e is useful in examples and integration tests, it does not modify the behavior of the library directly.\u003c/p\u003e\n"]]],[],null,["Version 2.31.0keyboard_arrow_down\n\n- [2.42.0-rc (latest)](/cpp/docs/reference/retail/latest/retail-env)\n- [2.41.0](/cpp/docs/reference/retail/2.41.0/retail-env)\n- [2.40.0](/cpp/docs/reference/retail/2.40.0/retail-env)\n- [2.39.0](/cpp/docs/reference/retail/2.39.0/retail-env)\n- [2.38.0](/cpp/docs/reference/retail/2.38.0/retail-env)\n- [2.37.0](/cpp/docs/reference/retail/2.37.0/retail-env)\n- [2.36.0](/cpp/docs/reference/retail/2.36.0/retail-env)\n- [2.35.0](/cpp/docs/reference/retail/2.35.0/retail-env)\n- [2.34.0](/cpp/docs/reference/retail/2.34.0/retail-env)\n- [2.33.0](/cpp/docs/reference/retail/2.33.0/retail-env)\n- [2.32.0](/cpp/docs/reference/retail/2.32.0/retail-env)\n- [2.31.0](/cpp/docs/reference/retail/2.31.0/retail-env)\n- [2.30.0](/cpp/docs/reference/retail/2.30.0/retail-env)\n- [2.29.0](/cpp/docs/reference/retail/2.29.0/retail-env)\n- [2.28.0](/cpp/docs/reference/retail/2.28.0/retail-env)\n- [2.27.0](/cpp/docs/reference/retail/2.27.0/retail-env)\n- [2.26.0](/cpp/docs/reference/retail/2.26.0/retail-env)\n- [2.25.1](/cpp/docs/reference/retail/2.25.1/retail-env)\n- [2.24.0](/cpp/docs/reference/retail/2.24.0/retail-env)\n- [2.23.0](/cpp/docs/reference/retail/2.23.0/retail-env)\n- [2.22.1](/cpp/docs/reference/retail/2.22.1/retail-env)\n- [2.21.0](/cpp/docs/reference/retail/2.21.0/retail-env)\n- [2.20.0](/cpp/docs/reference/retail/2.20.0/retail-env)\n- [2.19.0](/cpp/docs/reference/retail/2.19.0/retail-env)\n- [2.18.0](/cpp/docs/reference/retail/2.18.0/retail-env)\n- [2.17.0](/cpp/docs/reference/retail/2.17.0/retail-env)\n- [2.16.0](/cpp/docs/reference/retail/2.16.0/retail-env)\n- [2.15.1](/cpp/docs/reference/retail/2.15.1/retail-env)\n- [2.14.0](/cpp/docs/reference/retail/2.14.0/retail-env)\n- [2.13.0](/cpp/docs/reference/retail/2.13.0/retail-env)\n- [2.12.0](/cpp/docs/reference/retail/2.12.0/retail-env)\n- [2.11.0](/cpp/docs/reference/retail/2.11.0/retail-env) \n\nEnvironment Variables\n=====================\n\nA 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.\n\nEndpoint Overrides\n------------------\n\n- `GOOGLE_CLOUD_CPP_ANALYTICS_SERVICE_ENDPOINT=...` overrides the `EndpointOption` (which defaults to \"retail.googleapis.com\") used by `MakeAnalyticsServiceConnection()`.\n- `GOOGLE_CLOUD_CPP_CATALOG_SERVICE_ENDPOINT=...` overrides the `EndpointOption` (which defaults to \"retail.googleapis.com\") used by `MakeCatalogServiceConnection()`.\n- `GOOGLE_CLOUD_CPP_COMPLETION_SERVICE_ENDPOINT=...` overrides the `EndpointOption` (which defaults to \"retail.googleapis.com\") used by `MakeCompletionServiceConnection()`.\n- `GOOGLE_CLOUD_CPP_CONTROL_SERVICE_ENDPOINT=...` overrides the `EndpointOption` (which defaults to \"retail.googleapis.com\") used by `MakeControlServiceConnection()`.\n- `GOOGLE_CLOUD_CPP_MODEL_SERVICE_ENDPOINT=...` overrides the `EndpointOption` (which defaults to \"retail.googleapis.com\") used by `MakeModelServiceConnection()`.\n- `GOOGLE_CLOUD_CPP_PRODUCT_SERVICE_ENDPOINT=...` overrides the `EndpointOption` (which defaults to \"retail.googleapis.com\") used by `MakeProductServiceConnection()`.\n- `GOOGLE_CLOUD_CPP_RETAIL_PREDICTION_SERVICE_ENDPOINT=...` overrides the `EndpointOption` (which defaults to \"retail.googleapis.com\") used by `MakePredictionServiceConnection()`.\n- `GOOGLE_CLOUD_CPP_SEARCH_SERVICE_ENDPOINT=...` overrides the `EndpointOption` (which defaults to \"retail.googleapis.com\") used by `MakeSearchServiceConnection()`.\n- `GOOGLE_CLOUD_CPP_SERVING_CONFIG_SERVICE_ENDPOINT=...` overrides the `EndpointOption` (which defaults to \"retail.googleapis.com\") used by `MakeServingConfigServiceConnection()`.\n- `GOOGLE_CLOUD_CPP_USER_EVENT_SERVICE_ENDPOINT=...` overrides the `EndpointOption` (which defaults to \"retail.googleapis.com\") used by `MakeUserEventServiceConnection()`.\n\n###### See Also\n\n[`google::cloud::EndpointOption`](https://cloud.google.com/cpp/docs/reference/common/latest/structgoogle_1_1cloud_1_1EndpointOption.html)\n\nLogging\n-------\n\n`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.\n\n###### See Also\n\n[`google::cloud::LoggingComponentsOption`](https://cloud.google.com/cpp/docs/reference/common/latest/structgoogle_1_1cloud_1_1LoggingComponentsOption.html)`GOOGLE_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.\n\n###### See Also\n\n[`google::cloud::GrpcTracingOptionsOption`](https://cloud.google.com/cpp/docs/reference/common/latest/structgoogle_1_1cloud_1_1GrpcTracingOptionsOption.html)`GOOGLE_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.\n\n###### See Also\n\n[`google::cloud::LogBackend`](https://cloud.google.com/cpp/docs/reference/common/latest/classgoogle_1_1cloud_1_1LogBackend.html)\n\n###### See Also\n\n[`google::cloud::LogSink`](https://cloud.google.com/cpp/docs/reference/common/latest/classgoogle_1_1cloud_1_1LogSink.html)\n\nSetting the Default Project\n---------------------------\n\n`GOOGLE_CLOUD_PROJECT=...`: is used in examples and integration tests to configure the GCP project. This has no effect in the library."]]
