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

• L1Contract.sol
• L2Contract.sol
• deployL1.js
• deployL2.js
• getRelayFee.js
• sendL1ToL2Message.js
• getGreetingOnL2.js

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