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_DATASTREAM_ENDPOINT=... overrides the EndpointOption (which defaults to "datastream.googleapis.com") used by MakeDatastreamConnection().
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::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 2025-03-05 UTC."],[[["This document details various versions of the Datastream library, ranging from version 2.11.0 up to the latest release candidate 2.37.0-rc, with version 2.26.0 being specifically highlighted."],["Environment variables like `GOOGLE_CLOUD_CPP_DATASTREAM_ENDPOINT` can be used to override default settings such as the endpoint for `MakeDatastreamConnection()`."],["Tracing for gRPC calls can be enabled via `GOOGLE_CLOUD_CPP_ENABLE_TRACING=rpc`, which will output request and response information, typically requiring `GOOGLE_CLOUD_CPP_ENABLE_CLOG` for console visibility."],["Logging in the library is toggled using `GOOGLE_CLOUD_CPP_ENABLE_CLOG=yes`, enabling the output of log messages to the console."],["The `GOOGLE_CLOUD_PROJECT` variable can be set to influence examples and integration tests, but it does not affect library behavior."]]],[]]
