grpcat

Arbitrary gRPC message sender - grpcat is netcat for gRPC.

Usage

Given a protobuf definition, hello.proto, compile it to python:

$ python3 -m grpc_tools.protoc -I. --python_out=. --grpc_python_out=. hello.proto

Given a service called Hello listening on localhost port 4444, call the GetHello RPC with a GetHelloRequest message parsed from text:

$ cat get_hello_request.txt | grpcat.py localhost 4444 /hello.Hello/GetHello GetHelloRequest

The response from that request will be printed to stdout.

Assumptions

grpcat assume Python 3. Additionally, at version 0.1 grpcat assumes that the compiled protobuf files are in the current working directory.

Testing

The test program unit_tests.py tests grpcat.py for the following functionality: valid command parsing from program arguments and a successful RPC server connection.

Specifically whether the program

• reads in the command line arguments as excpected
• produces the appropriate error messages on too few or too many commands
• produces the appropriate error on an invalid target service format
• fails to make a connection to the RPC server
• succeeds in connecting to the RPC server

Assumptions

• compiled modules from hello.proto
• a get_hello_request.txt with a valid message, with the appropriate field specified in the hello.proto, for example name:"Joe".

Usage

Run unit the unit tests the following way:

$ python3 unit_tests.py

The program will output the results of the unit tests.

Copyright

grpcat is distributed under the MIT License and is copyright 2017 Gyroscope Software.

grpcat includes contributions by Daniel Osváth Londoño.