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
PUBSUB_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.
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 2025-05-07 UTC."],[[["This document provides a comprehensive list of Pub/Sub C++ library versions, ranging from the latest release candidate 2.37.0-rc down to version 2.11.0, with direct links to the documentation for each."],["Environment variables like `PUBSUB_EMULATOR_HOST`, `GOOGLE_CLOUD_CPP_ENABLE_TRACING`, `GOOGLE_CLOUD_CPP_TRACING_OPTIONS`, and `GOOGLE_CLOUD_CPP_ENABLE_CLOG` can be set to configure and troubleshoot the behavior of the library, such as connecting to an emulator or enabling gRPC call tracing."],["The `GOOGLE_CLOUD_PROJECT` environment variable is utilized in examples and tests to set the GCP project, although it does not have any impact on the library's core functionality."],["The document references various options and classes within the `google::cloud` namespace for advanced configurations like endpoints, logging components, and gRPC tracing, and directs users to those resources for more detailed information."]]],[]]
