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_CLOUD_CHANNEL_REPORTS_SERVICE_ENDPOINT=...overrides theEndpointOption(which defaults to "cloudchannel.googleapis.com") used byMakeCloudChannelReportsServiceConnection().
GOOGLE_CLOUD_CPP_CLOUD_CHANNEL_SERVICE_ENDPOINT=...overrides theEndpointOption(which defaults to "cloudchannel.googleapis.com") used byMakeCloudChannelServiceConnection().
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::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 2025-09-04 UTC."],[[["\u003cp\u003eThis document provides reference information for various versions of a C++ library, ranging from version 2.11.0 up to the release candidate 2.37.0-rc, with links to their respective documentation.\u003c/p\u003e\n"],["\u003cp\u003eEnvironment variables can be used to configure the behavior of the library, offering a convenient way to adjust settings, especially for troubleshooting, and there are functions available to do this via code.\u003c/p\u003e\n"],["\u003cp\u003eThe library's default endpoint, which is "cloudchannel.googleapis.com", can be overridden using specific environment variables for both Cloud Channel Reports Service and Cloud Channel Service.\u003c/p\u003e\n"],["\u003cp\u003eTracing and logging for gRPC calls can be enabled and configured 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.\u003c/p\u003e\n"],["\u003cp\u003eThe \u003ccode\u003eGOOGLE_CLOUD_PROJECT\u003c/code\u003e variable can be used to configure the GCP project in examples and integration tests, but is not used by the library itself.\u003c/p\u003e\n"]]],[],null,["Version 2.19.0keyboard_arrow_down\n\n- [2.42.0-rc (latest)](/cpp/docs/reference/channel/latest/channel-env)\n- [2.41.0](/cpp/docs/reference/channel/2.41.0/channel-env)\n- [2.40.0](/cpp/docs/reference/channel/2.40.0/channel-env)\n- [2.39.0](/cpp/docs/reference/channel/2.39.0/channel-env)\n- [2.38.0](/cpp/docs/reference/channel/2.38.0/channel-env)\n- [2.37.0](/cpp/docs/reference/channel/2.37.0/channel-env)\n- [2.36.0](/cpp/docs/reference/channel/2.36.0/channel-env)\n- [2.35.0](/cpp/docs/reference/channel/2.35.0/channel-env)\n- [2.34.0](/cpp/docs/reference/channel/2.34.0/channel-env)\n- [2.33.0](/cpp/docs/reference/channel/2.33.0/channel-env)\n- [2.32.0](/cpp/docs/reference/channel/2.32.0/channel-env)\n- [2.31.0](/cpp/docs/reference/channel/2.31.0/channel-env)\n- [2.30.0](/cpp/docs/reference/channel/2.30.0/channel-env)\n- [2.29.0](/cpp/docs/reference/channel/2.29.0/channel-env)\n- [2.28.0](/cpp/docs/reference/channel/2.28.0/channel-env)\n- [2.27.0](/cpp/docs/reference/channel/2.27.0/channel-env)\n- [2.26.0](/cpp/docs/reference/channel/2.26.0/channel-env)\n- [2.25.1](/cpp/docs/reference/channel/2.25.1/channel-env)\n- [2.24.0](/cpp/docs/reference/channel/2.24.0/channel-env)\n- [2.23.0](/cpp/docs/reference/channel/2.23.0/channel-env)\n- [2.22.1](/cpp/docs/reference/channel/2.22.1/channel-env)\n- [2.21.0](/cpp/docs/reference/channel/2.21.0/channel-env)\n- [2.20.0](/cpp/docs/reference/channel/2.20.0/channel-env)\n- [2.19.0](/cpp/docs/reference/channel/2.19.0/channel-env)\n- [2.18.0](/cpp/docs/reference/channel/2.18.0/channel-env)\n- [2.17.0](/cpp/docs/reference/channel/2.17.0/channel-env)\n- [2.16.0](/cpp/docs/reference/channel/2.16.0/channel-env)\n- [2.15.1](/cpp/docs/reference/channel/2.15.1/channel-env)\n- [2.14.0](/cpp/docs/reference/channel/2.14.0/channel-env)\n- [2.13.0](/cpp/docs/reference/channel/2.13.0/channel-env)\n- [2.12.0](/cpp/docs/reference/channel/2.12.0/channel-env)\n- [2.11.0](/cpp/docs/reference/channel/2.11.0/channel-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_CLOUD_CHANNEL_REPORTS_SERVICE_ENDPOINT=...` overrides the `EndpointOption` (which defaults to \"cloudchannel.googleapis.com\") used by `MakeCloudChannelReportsServiceConnection()`.\n- `GOOGLE_CLOUD_CPP_CLOUD_CHANNEL_SERVICE_ENDPOINT=...` overrides the `EndpointOption` (which defaults to \"cloudchannel.googleapis.com\") used by `MakeCloudChannelServiceConnection()`.\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::TracingComponentsOption`](https://cloud.google.com/cpp/docs/reference/common/latest/structgoogle_1_1cloud_1_1TracingComponentsOption.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."]]
