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_DATASTORE_ADMIN_ENDPOINT=...overrides theEndpointOption(which defaults to "datastore.googleapis.com") used byMakeDatastoreAdminConnection().
GOOGLE_CLOUD_CPP_DATASTORE_ENDPOINT=...overrides theEndpointOption(which defaults to "datastore.googleapis.com") used byMakeDatastoreConnection().
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\u003eThe latest release candidate version for the datastore is 2.37.0-rc, which is available alongside multiple previous versions, down to version 2.15.1.\u003c/p\u003e\n"],["\u003cp\u003eEnvironment variables offer a way to adjust the library's behavior, primarily useful for troubleshooting purposes, and also complement the in-code configuration options.\u003c/p\u003e\n"],["\u003cp\u003e\u003ccode\u003eGOOGLE_CLOUD_CPP_DATASTORE_ADMIN_ENDPOINT\u003c/code\u003e and \u003ccode\u003eGOOGLE_CLOUD_CPP_DATASTORE_ENDPOINT\u003c/code\u003e environment variables allow users to override the default endpoints used by the \u003ccode\u003eMakeDatastoreAdminConnection()\u003c/code\u003e and \u003ccode\u003eMakeDatastoreConnection()\u003c/code\u003e functions respectively.\u003c/p\u003e\n"],["\u003cp\u003eEnabling gRPC call tracing is possible by setting \u003ccode\u003eGOOGLE_CLOUD_CPP_ENABLE_TRACING=rpc\u003c/code\u003e, which can be further enhanced by also setting \u003ccode\u003eGOOGLE_CLOUD_CPP_ENABLE_CLOG\u003c/code\u003e to see the output in the program's console.\u003c/p\u003e\n"],["\u003cp\u003eSetting the environment variable \u003ccode\u003eGOOGLE_CLOUD_PROJECT\u003c/code\u003e will affect the examples and integration tests, but not the library itself.\u003c/p\u003e\n"]]],[],null,["Version 2.27.0keyboard_arrow_down\n\n- [2.42.0-rc (latest)](/cpp/docs/reference/datastore/latest/datastore-env)\n- [2.41.0](/cpp/docs/reference/datastore/2.41.0/datastore-env)\n- [2.40.0](/cpp/docs/reference/datastore/2.40.0/datastore-env)\n- [2.39.0](/cpp/docs/reference/datastore/2.39.0/datastore-env)\n- [2.38.0](/cpp/docs/reference/datastore/2.38.0/datastore-env)\n- [2.37.0](/cpp/docs/reference/datastore/2.37.0/datastore-env)\n- [2.36.0](/cpp/docs/reference/datastore/2.36.0/datastore-env)\n- [2.35.0](/cpp/docs/reference/datastore/2.35.0/datastore-env)\n- [2.34.0](/cpp/docs/reference/datastore/2.34.0/datastore-env)\n- [2.33.0](/cpp/docs/reference/datastore/2.33.0/datastore-env)\n- [2.32.0](/cpp/docs/reference/datastore/2.32.0/datastore-env)\n- [2.31.0](/cpp/docs/reference/datastore/2.31.0/datastore-env)\n- [2.30.0](/cpp/docs/reference/datastore/2.30.0/datastore-env)\n- [2.29.0](/cpp/docs/reference/datastore/2.29.0/datastore-env)\n- [2.28.0](/cpp/docs/reference/datastore/2.28.0/datastore-env)\n- [2.27.0](/cpp/docs/reference/datastore/2.27.0/datastore-env)\n- [2.26.0](/cpp/docs/reference/datastore/2.26.0/datastore-env)\n- [2.25.1](/cpp/docs/reference/datastore/2.25.1/datastore-env)\n- [2.24.0](/cpp/docs/reference/datastore/2.24.0/datastore-env)\n- [2.23.0](/cpp/docs/reference/datastore/2.23.0/datastore-env)\n- [2.22.1](/cpp/docs/reference/datastore/2.22.1/datastore-env)\n- [2.21.0](/cpp/docs/reference/datastore/2.21.0/datastore-env)\n- [2.20.0](/cpp/docs/reference/datastore/2.20.0/datastore-env)\n- [2.19.0](/cpp/docs/reference/datastore/2.19.0/datastore-env)\n- [2.18.0](/cpp/docs/reference/datastore/2.18.0/datastore-env)\n- [2.17.0](/cpp/docs/reference/datastore/2.17.0/datastore-env)\n- [2.16.0](/cpp/docs/reference/datastore/2.16.0/datastore-env)\n- [2.15.1](/cpp/docs/reference/datastore/2.15.1/datastore-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_DATASTORE_ADMIN_ENDPOINT=...` overrides the `EndpointOption` (which defaults to \"datastore.googleapis.com\") used by `MakeDatastoreAdminConnection()`.\n- `GOOGLE_CLOUD_CPP_DATASTORE_ENDPOINT=...` overrides the `EndpointOption` (which defaults to \"datastore.googleapis.com\") used by `MakeDatastoreConnection()`.\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."]]
