l1-confirmation-checker

L1 Confirmation Checker Tutorial

l1 confirmation checker is a simple demo of Arbitrum's transaction finality checker (used to check if transaction submitted to l1 or not).

It calls precompile NodeInterface to find information about an L1 transaction that posted the L2 transaction in a batch.

It has 2 functions; both functions will show you whether your L2 transaction has been posted in an L1 batch. The first function, checkConfirmation, will output the number of L1 block confirmations the L1 batch-posting transaction has. The second is findSubmissionTx, which will output the L1 batch-posting transaction hash.

See ./exec.js for inline explanations.

Run Demo:

Check if tx recorded in L1 or not:

yarn checkConfirmation --txHash {YOUR_TX_HASH}

Get submissiontx by a given L2 transaction status:

yarn findSubmissionTx --txHash {YOUR_TX_HASH}

Config Environment Variables

Set the values shown in .env-sample as environmental variables. To copy it into a .env file:

cp .env-sample .env

(you'll still need to edit some variables, i.e., DEVNET_PRIVKEY)