Assignment on RFModule and YARP thrift IDL

In this assignment (assignment_Codec) you are asked to add a service interface (using YARP thrift IDL) to the previously developed module during the tutorial_RFModule.

Assignment

During the tutorial_RFModule we have developed a module to encode and decode string messages. The module could work as coder or decoder depending on its parameters :

$ tutorial_RFModule --mode coder
$ tutorial_RFModule --mode decoder

It had an input port to receive text messages, an output port to steam out the encoded/decoded messages. Now you need to add a RPC port (lets call it "/Codec/rpc") for the remote and runtime configuration of the module:

Via this RPC port we should be able to call the following methods:

1. set_mode() which accept a string (i.e. coder, decoder) and switch the module behavior between coding and decoding mode.
2. get_mode() returns an string showing the module current mode (i.e. coder, decoder).
3. set_codec() accepts an integer (i.e. the ASCII code of a character) and uses it to encode/decode the string.

What do you need to do?

Not so much! ;)

• Modify the file src/idl/assignment_Codec.thrift to add the above methods in thrift IDL format.
• Modify the file src/Codec.h to add the missing interfaces of Codec_IDL class
• Modify the file src/Codec.cpp to implement the missing interface of Codec_IDL class

Build and Install the code

Follow these steps to build and properly install your module:

$ cd assignment_Codec
$ mkdir build; cd build
$ cmake ../
$ make
$ make install

Running cmake and make will automatically call yarpidl_thrift on your src/idl/assignment_Codec.thrift and generate the corresponding code into build directory:

• build/include/src/idl/Codec_IDL.h
• build/src/Codec_IDL.cpp

Notice: you do not need to modify these files. So every time you update the assignment_Codec.thrift file, you just need to rerun the make and it will update the corresponding (generated) files :)

The make install will also install your module (binary, xml files, etc) in the icub contrib folder which is already setup on your machine.

Testing your code

• open a terminal and run assignment_Codec

$ assignment_Codec
[INFO]Configuring the codedc module...
yarp: Port /Codec/rpc active at tcp://127.0.0.1:10002/
yarp: Port /Codec/in active at tcp://127.0.0.1:10003/
yarp: Port /Codec/out active at tcp://127.0.0.1:10004/

• In another terminal run yarp read

$ yarp read ... /Codec/out

• In another terminal run yarp write and type something

$ yarp write ... /Codec/in
>> hello

You should be able to see the codec message (i.e. "(%,,/")in the yarp read terminal.

• In a terminal run yarp rpc and check your interfaces

$ yarp rpc /Codec/rpc
>> get_mode
Response: coder
>> set_mode decoder
Response: [ok]

Now if you write a "(%,,/" in the yarp write terminal you should be able to see the encoded message (i.e. hello) in the yarp read terminal.

Run the smoke test

Close the assignment_Codec module (e.g. press CTRL+C) and other terminals. switch to the smoke-test folder and run the test:

$ cd assignment_Codec/smoke-test
$ ./test.sh

How to complete the assignment