Accounts

This tutorial demonstrates how to make a simple interchain call using the Accounts API to a pre-deployed TestRecipient contract on a remote chain.

You can also check out the hyperlane-quickstart repo for running this out of the box.

Want to learn more about interchain accounts? Take a look at the Accounts API documentation

Inputs

• $DESTINATION_DOMAIN: The domain ID of the destination chain. See Domain identifiers

• $RECIPIENT: The address of the TestRecipient contract on the destination chain,0x36FdA966CfffF8a9Cdc814f546db0e6378bFef35

• $CALLDATA: The calldata of the call to make on TestRecipient, which we generate using cast: 0xf07c1f4700000000000000000000000000000000000000000000000000000000000000010000000000000000000000000000000000000000000000000000000000000040000000000000000000000000000000000000000000000000000000000000001648656c6c6f576f726c642066726f6d20616e2049434100000000000000000000

$ cast calldata "fooBar(uint256,string)" 1 "HelloWorld from an ICA"

Make a call

Sending a message is a simple matter of calling InterchainAccountRouter.callRemote(). This function can be called easily using Etherscan+Metamask or cast.

Using Metamask

1. Navigate to the InterchainAccountRouter contract page on Etherscan (or whatever chain you want to send from). See Contract addresses for InterchainAccountRouter addresses

2. Under the Contract tab, find the Write as Proxy button.

3. Click on the Connect to Web3 button to connect your Wallet (i.e. Metamask). Make sure that you are on the correct network.

4. Expand the callRemote box

5. For destination domain, enter $DESTINATION_DOMAIN. You could use 137 to send to mainnet Polygon, or see other Domain identifiers

6. For the _to argument, enter the $RECIPIENT

7. For the _value argument, enter 0

8. For the _data argument, enter the $CALLDATA

9. Submit the transaction via your wallet/Metamask

Using cast

You can call the InterchainAccountRouter directly using cast. Make sure that you have a valid RPC URL for the origin chain and a private key with which you can pay for gas.

cast send 0xE0Be420779cAd6E2bEA1E4F7C02F996D9ED1fCB5 \
  'callRemote(uint32,address,uint256,bytes)' \
  $DESTINATION_DOMAIN $RECIPIENT 0 $CALLDATA \
  --rpc-url $RPC_URL --private-key $PRIVATE_KEY

If you view the transaction on a block explorer, you should be able to see the Dispatch event. You can see an example message sending transaction here.

For your call to be executed on the destination chain, you must Manually pay for interchain gas, using 550000 for the gas amount

pageManually pay for interchain gas