How do you test and debug protobuf messages and services in C++?

1 Generate and compile code

The first step is to generate C++ code from your protobuf schema, which defines the structure and types of your messages and services. You can use the protoc compiler to do this, with the --cpp_out and --grpc_out options. This will create .h and .cc files that you can include and link in your C++ project. You should also install the protobuf and gRPC libraries and headers, and make sure they are compatible with your protoc version.

3 Use logging and tracing

The third step is to use logging and tracing to monitor and debug your protobuf messages and services. You can use the built-in logging features of protobuf and gRPC, or use a third-party library, such as spdlog, glog, or opentelemetry. You should configure the logging level, format, and destination, and use consistent and informative messages. You should also use tracing to track the flow and performance of your requests and responses, and identify bottlenecks and errors.

4 Use debugging tools

The fourth step is to use debugging tools to inspect and manipulate your protobuf messages and services. You can use a debugger, such as gdb or lldb, to set breakpoints, examine variables, and step through code. You can also use a tool, such as protoc-gen-inspect or protoc-gen-debug, to generate human-readable output from your binary messages. You can also use a tool, such as grpcurl or grpc_cli, to interact with your services from the command line.

5 Use testing tools

The fifth step is to use testing tools to simulate and verify your protobuf messages and services. You can use a tool, such as protoc-gen-mock or grpc-mock, to generate mock objects that mimic the behavior of your services. You can also use a tool, such as grpcui or bloomrpc, to create and send requests and responses from a graphical interface. You can also use a tool, such as grpc-dump or wireshark, to capture and analyze network traffic.