examples.communication_schemes package

Submodules

examples.communication_schemes.channeling_example module

Channeling Example using Wrapyfi.

This script demonstrates message channeling through three different middleware (A, B, and C) using the MiddlewareCommunicator within the Wrapyfi library. It allows message publishing and listening functionalities between processes or machines.

Demonstrations:

• Using NativeObject, Image, and AudioChunk messages

• Transmitting messages through different middlewares (e.g., ROS, YARP, ZeroMQ)

• Applying the PUB/SUB pattern with channeling

Requirements:

• Wrapyfi: Middleware communication wrapper (refer to the Wrapyfi documentation for installation instructions)

• YARP, ROS, ROS 2, ZeroMQ (refer to the Wrapyfi documentation for installation instructions)

• NumPy: Used for creating arrays (installed with Wrapyfi)

Install using pip:

pip install numpy

Run:

# On machine 1 (or process 1): Mode: Publisher sends messages through channels A [ZeroMQ], B [ROS 2], and C [YARP]

python3 channeling_example.py --mode publish --mware_A zeromq --mware_B ros2 --mware_C yarp

# On machine 2 (or process 2): Mode: Listener waits for message from channels A [ZeroMQ], B [ROS 2], and C [YARP]

python3 channeling_example.py --mode listen --mware_A zeromq --mware_B ros2 --mware_C yarp

# On machine 3 (or process 3): Mode: Listener waits for message from channel C [YARP]

python3 channeling_example.py --mode listen --mware_C yarp

# On machine 4 (or process 4) [OPTIONAL]: Mode: Listener waits for message from channel B [ROS 2]

python3 channeling_example.py --mode listen --mware_B ros2

class examples.communication_schemes.channeling_example.ChannelingCls

Bases: MiddlewareCommunicator

read_mulret_mulmware(img_width=200, img_height=200, aud_rate=44100, aud_chunk=8820, aud_channels=1, mware_A=None, mware_B=None, mware_C=None)

Read and forward messages through channels A, B, and C.

examples.communication_schemes.channeling_example.parse_args()

Parse command line arguments.

examples.communication_schemes.channeling_example.main(args)

Main function to initiate ChannelingCls class and communication.

examples.communication_schemes.forwarding_example module

Forwarding Example using Wrapyfi.

This script demonstrates message forwarding using the MiddlewareCommunicator within the Wrapyfi library. The communication follows chained forwarding through two methods, enabling PUB/SUB pattern that allows message publishing and listening functionalities between processes or machines.

Demonstrations:

• Using the NativeObject message

• Transmitting a Python object with predefined message

• Applying the PUB/SUB pattern with forwarding through two communication methods

Requirements:

• Wrapyfi: Middleware communication wrapper (refer to the Wrapyfi documentation for installation instructions)

• YARP, ROS, ROS 2, ZeroMQ (refer to the Wrapyfi documentation for installation instructions)

Run:

# On machine 1 (or process 1): Mode Chain A: Publisher [ZeroMQ], Chain B: Disabled (chain A & B can have different middleware by setting the –mware_… argument but it should be consistent on all machines or processes)

python3 forwarding_example.py --mware_chain_A zeromq --mode_chain_A publish --mode_chain_B disable

# On machine 2 (or process 2): Mode Chain A: Listener [ZeroMQ], Chain B: Publisher [ROS 2] (chain A & B can have different middleware by setting the –mware_… argument but it should be consistent on all machines or processes)

python3 forwarding_example.py --mware_chain_A zeromq --mode_chain_A listen --mware_chain_B ros2 --mode_chain_B publish

# On machine 3 (or process 3): Mode Chain A: Disabled, Chain B: Listener [ROS 2] (chain A & B can have different middleware by setting the –mware_… argument but it should be consistent on all machines or processes)

python3 forwarding_example.py --mode_chain_A disable --mware_chain_B ros2 --mode_chain_B listen

class examples.communication_schemes.forwarding_example.ForwardCls

Bases: MiddlewareCommunicator

read_chain_A(mware_chain_A=None, msg='')

Read and forward message from chain A.

read_chain_B(mware_chain_B=None, msg='')

Read and forward message from chain B.

examples.communication_schemes.forwarding_example.parse_args()

Parse command line arguments.

examples.communication_schemes.forwarding_example.main(args)

Main function to initiate ForwardCls class and communication.

examples.communication_schemes.mirroring_example module

Mirroring Example using Wrapyfi.

This script demonstrates the capability to mirror messages using the MiddlewareCommunicator within the Wrapyfi library. The communication follows the PUB/SUB and REQ/REP patterns, allowing message publishing, listening, requesting, and replying functionalities between processes or machines.

Demonstrations:

• Using the NativeObject message

• Transmitting a Python object with user input and predefined message

• Applying the PUB/SUB and REQ/REP patterns with mirroring

Requirements:

• Wrapyfi: Middleware communication wrapper (refer to the Wrapyfi documentation for installation instructions)

• YARP, ROS, ROS 2, ZeroMQ (refer to the Wrapyfi documentation for installation instructions)

Run:

# Alternative 1: PUB/SUB

# On machine 1 (or process 1): Publishing mode - Publisher waits for keyboard input and transmits message

python3 mirroring_example.py --mode publish

# On machine 2 (or process 2): Listening mode - Listener waits for message and prints the received object

python3 mirroring_example.py --mode listen

# Alternative 2: REQ/REP

# On machine 1 (or process 1): Replying mode - Replier waits for a message, sends a reply, and prints the received object

python3 mirroring_example.py --mode reply

# On machine 2 (or process 2): Requesting mode - Requester sends a predefined message and waits for a reply

python3 mirroring_example.py --mode request

class examples.communication_schemes.mirroring_example.MirrorCls

Bases: MiddlewareCommunicator

read_msg(mware=None, msg='', blocking=True)

Exchange messages and mirror user input.

examples.communication_schemes.mirroring_example.parse_args()

Parse command line arguments.

examples.communication_schemes.mirroring_example.main(args)

Main function to initiate MirrorCls class and communication.

Module contents