Scroll zkEVM Messenger L1->L2 Example

Send a message from L1 Goerli to L2 Scroll zkEVM testnet.

Example

There's two contracts; L2Contract.sol and L1Contract.sol

The L1 contract has a method sendMessageToL2 that sends a message from L1 to L2 contract to set a greeting message on L2 contract. It sends the encoded calldata to execute setGreeting on L2 which can only be called if the message was sent by the L1 contract.

Files

Install

git clone https://github.com/miguelmota/scroll-messenger-l1-to-l2-example.git
cd scroll-messenger-l1-to-l2-example
npm install

Set Signer

Create .env

PRIVATE_KEY=123...

Make sure private key has funds on both Goerli and Scroll zkEVM testnet.

Compile Contracts

npx hardhat compile

Deploy L1 Contract

Command

npx hardhat run --network goerli scripts/deployL1.js

Output

L1Contract deployed to: 0x41Ed7bd26747d2BE681795443C9e76c7fa3f9880

Deploy L2 Contract

Command

L1_CONTRACT=0x41Ed7bd26747d2BE681795443C9e76c7fa3f9880 \
npx hardhat run --network scroll scripts/deployL2.js

Output

L2Contract deployed to: 0x6310B81901A64DDF04Ca83fc9904Df9833721d4F

Get Relay Fee

Command

npx hardhat run --network goerli scripts/getRelayFee.js

Output

l2BaseFee: 0.00000000002
gasLimit: 500000
fee: 0.00001

Send L1->L2 Message

Command (replace env vars with your values)

GREETING="hello world" \
L1_CONTRACT=0x41Ed7bd26747d2BE681795443C9e76c7fa3f9880 \
L2_CONTRACT=0x6310B81901A64DDF04Ca83fc9904Df9833721d4F \
npx hardhat run --network goerli scripts/sendL1ToL2Message.js

Output

sent tx hash 0xf684e3bd4f176f86be5ee4664765a1d6af74096eedbbf001ead36bf8302c0bb0
https://goerli.etherscan.io/tx/0xf684e3bd4f176f86be5ee4664765a1d6af74096eedbbf001ead36bf8302c0bb0

Get Greeting on L2

Command (Note: must wait 8-14 minutes after sending from L1 to see updated state on L2)

L2_CONTRACT=0x6310B81901A64DDF04Ca83fc9904Df9833721d4F \
npx hardhat run --network scroll scripts/getGreetingOnL2.js

Output

greeting: hello world

Send L2->L1 Message

See https://github.com/miguelmota/scroll-messenger-l2-to-l1-example

License

MIT @ Miguel Mota