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
BIGTABLE_EMULATOR_HOST=host:port: tells the library to connect to the specified emulator rather than the default endpoint. Intended for testing only.
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.
GOOGLE_CLOUD_CPP_ENABLE_TRACING=rpc-streams: turns on tracing for streaming gRPC calls, such as Table::ReadRows(). Be warned that streams produce a lot of output.
GOOGLE_CLOUD_CPP_ENABLE_TRACING=rpc,rpc-streams: turns on tracing for both regular RPC calls and streaming RPC calls.
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 2025-03-05 UTC."],[[["The webpage documents various versions of the Bigtable C++ client library, ranging from version 2.11.0 up to the release candidate 2.37.0-rc, with links to documentation for each version."],["Environment variables can be used to configure the Bigtable C++ client library's behavior, providing a convenient way to troubleshoot issues."],["The `BIGTABLE_EMULATOR_HOST` environment variable allows users to connect the library to a specific emulator for testing purposes, rather than the default endpoint."],["The `GOOGLE_CLOUD_CPP_ENABLE_TRACING` variable enables detailed tracing for gRPC calls, and `GOOGLE_CLOUD_CPP_ENABLE_CLOG` activates logging, which can then be used for rpc or rpc-streams tracing."],["`GOOGLE_CLOUD_PROJECT` is used for setting the GCP project in examples and tests, although it does not directly affect the library's operation."]]],[]]