Retrieving Interchain Messenger from the Registry

Use Registry in a Cross-Chain dApp.

Let's now integrate the registry into a smart contract. Let's go back to the very simple string sending contract from the beginning:

contracts/interchain-messaging/registry/SenderOnCChainWithRegistry.sol

pragma solidity ^0.8.18;
 
import "@teleporter/upgrades/TeleporterRegistry.sol"; 
import "@teleporter/ITeleporterMessenger.sol";
 
contract SenderOnCChain {
    // The Interchain Messaging registry contract manages different Interchain Messaging contract versions.
    TeleporterRegistry public immutable teleporterRegistry = TeleporterRegistry(0x827364Da64e8f8466c23520d81731e94c8DDe510);
 
    /**
     * @dev Sends a message to another chain.
     */
    function sendMessage(address destinationAddress, string calldata message) external {
        ITeleporterMessenger messenger = teleporterRegistry.getLatestTeleporter();  
 
        messenger.sendCrossChainMessage(
            TeleporterMessageInput({
                // Replace with blockchainID of your Avalanche L1 (see instructions in Readme)
                destinationBlockchainID: 0x92756d698399805f0088fc07fc42af47c67e1d38c576667ac6c7031b8df05293,
                destinationAddress: destinationAddress,
                feeInfo: TeleporterFeeInfo({feeTokenAddress: address(0), amount: 0}),
                requiredGasLimit: 100000,
                allowedRelayerAddresses: new address[](0),
                message: abi.encode(message)
            })
        );
    }
}

Don't forget to replace the destinationBlockchainID with Blockchain ID (HEX) from your Avalanche L1!

The key things to understand:

We are importing the ITeleporterRegistry.sol interface
We have a variable for the registry address instead of the messenger address
Before sending the message we get the latest version from the registry

Retrieving Interchain Messenger from the Registry

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