Install and configure Solana CLI to use Devnet.

First create a new signer group:

cd cli
cargo run create-signer-group

Then generate a test Ethereum keypair, for example:

Address: 0xBCd61FAc303e9fc78fDf612A71AAa7a47a36b2d6
Private key: c8fa5fdef48a400fc1005d9e939d5b7b99b29bddd56bbd4272c40d5e38e7ca0a

Then create a new valid signer using created signer group and Ethereum address

cargo run create-valid-signer CytW3hKft44DL47PTEtvn29E8iRXchhNytxf1WEwy3Wh BCd61FAc303e9fc78fDf612A71AAa7a47a36b2d6

Where CytW3hKft44DL47PTEtvn29E8iRXchhNytxf1WEwy3Wh is signer group created on the previous step.

cd python_listener
pip3 install -r requirements.txt
python3 client.py

Listener will start listening for the new transactions on contract address.

Open new terminal window, then:

cd js_client
npm install

And try to send a message:

node index.js send-message FiNwLuqTdWC2ph1tk7xJzkr8mRwTYQx9rSmrEgh7TMaM c8fa5fdef48a400fc1005d9e939d5b7b99b29bddd56bbd4272c40d5e38e7ca0a "Test message" 

Where FiNwLuqTdWC2ph1tk7xJzkr8mRwTYQx9rSmrEgh7TMaM is your valid signer created with cargo run create-valid-signer command and c8fa5fdef48a400fc1005d9e939d5b7b99b29bddd56bbd4272c40d5e38e7ca0a is a private key to sign your message with.

Switch to the terminal running Python Listener. Message should appear there in a couple of seconds.