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_DATAPROC_METASTORE_ENDPOINT=... overrides the EndpointOption (which defaults to "metastore.googleapis.com") used by MakeDataprocMetastoreConnection().
GOOGLE_CLOUD_CPP_DATAPROC_METASTORE_FEDERATION_ENDPOINT=... overrides the EndpointOption (which defaults to "metastore.googleapis.com") used by MakeDataprocMetastoreFederationConnection().
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 2025-04-17 UTC."],[[["This page details environment variables and versioned documentation for configuring the behavior of the Dataproc Metastore C++ library, with the latest version being 2.37.0-rc."],["The `GOOGLE_CLOUD_CPP_DATAPROC_METASTORE_ENDPOINT` and `GOOGLE_CLOUD_CPP_DATAPROC_METASTORE_FEDERATION_ENDPOINT` variables are used to override the default endpoints for their respective connection methods."],["Setting `GOOGLE_CLOUD_CPP_ENABLE_TRACING=rpc` will turn on tracing for gRPC calls, requiring `GOOGLE_CLOUD_CPP_ENABLE_CLOG` to also be set to produce console output, while `GOOGLE_CLOUD_CPP_TRACING_OPTIONS` can be used to modify tracing behavior."],["Enabling logging in the library can be done by setting `GOOGLE_CLOUD_CPP_ENABLE_CLOG=yes`, allowing the logging infrastructure to print to a backend."],["While `GOOGLE_CLOUD_PROJECT` variable is used to configure the GCP project in examples and integration testing, it has no effect within the library itself."]]],[]]
