Contract interaction

On this page, you can find information on how to convert your ANTv1 to ANTv2 interacting directly with the smart contract. (For example, if your contract wallet can't send outward transactions).

This page contains technical information. It is provided for advanced users.

TL;DR

From a wallet holding ANTv1, you can upgrade all of its ANTv1 balance into ANTv2 by sending this approveAndCall() transaction:

to: 0x960b236A07cf122663c4303350609A66A7B288C0 (this is ANTv1's contract address)
data: 0xcae9ca51000000000000000000000000078bebc744b819657e1927bf41ab8c74cbbf912dffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff00000000000000000000000000000000000000000000000000000000000000600000000000000000000000000000000000000000000000000000000000000000

The ANTv2Migrator contract

The migration contract, deployed to 0x078BEbC744B819657e1927bF41aB8C74cBBF912D, facilitates the official upgrade of ANTv1 to ANTv2.

When a wallet upgrades its ANT balance through an on-chain interaction with this contract, the following happens:

1. ANTv2Migrator pulls the requested amount of ANTv1 from the wallet's balance into its own balance

2. ANTv2Migrator burns the pulled ANTv1 by transferring it to 0x000000000000000000000000000000000000dEaD

3. From its own balance, ANTv2Migrator sends the equivalent amount of ANTv2 back to the wallet

Interacting with the ANTv2Migrator

approveAndCall()

The simplest approach to completing the migration is by sending a single transaction. Calling ANTv1.approveAndCall(). approveAndCall() allows you to create an allowance to a contract and spend it in the same transaction.

To create such a call, you may pull out your favourite tool and use the following ABI:

[{"constant":false,"inputs":[{"name":"_spender","type":"address"},{"name":"_amount","type":"uint256"},{"name":"_extraData","type":"bytes"}],"name":"approveAndCall","outputs":[{"name":"success","type":"bool"}],"payable":false,"type":"function"}]

For the purposes of demonstration, I'll use the online ABI encoder provided by HashEx:

For the arguments, use:

• _spender: 0x078BEbC744B819657e1927bF41aB8C74cBBF912D (this is the migration contract's address)

• _amount: amount of ANTv1 to upgrade, denominated in wei (i.e. multiply by 1e18 for "decimal-correct" amounts)

• _extraData: can be left blank (not used)

Next, take the encoded data:

In the above screenshot, we have specified to only upgrade one (1) ANTv1.

You may now take this data and use it in a transaction where the to address is 0x960b236A07cf122663c4303350609A66A7B288C0 (this is ANTv1's address).

For example, to use the above data, you would send a transaction with the following data:

to: 0x960b236A07cf122663c4303350609A66A7B288C0
data: cae9ca51000000000000000000000000078bebc744b819657e1927bf41ab8c74cbbf912d0000000000000000000000000000000000000000000000000de0b6b3a764000000000000000000000000000000000000000000000000000000000000000000600000000000000000000000000000000000000000000000000000000000000000

For contract-based smart accounts and multisig wallets, they will typically have functions specifying the to and data components of a transaction.

Specify those accordingly based on the above output.

If you would prefer to use Etherscan, you may submit the above arguments directly to their ANTv1 contract interface:

Separate token allowances

If you prefer to not use an approveAndCall() transaction, you can upgrade in two steps by first creating an allowance (through ANTv1.approve()) for at least the amount desired to the migration contract at 0x078BEbC744B819657e1927bF41aB8C74cBBF912D, and then calling one of:

• migrate(uint256): Allows you to directly specify how much you would like to upgrade

• migrateAll(): Assumes you want to upgrade all of your balance (and that you have set an appropriate allowance)

Using an EscrowANTv2Migrator contract

In some situations, you may prefer to complete the upgrade without ever creating a token approval and only using vanilla ANTv1.transfer() interactions.

To do so, first deploy an EscrowANTv2Migrator configured with your desired recipient of the upgraded tokens and the account allowed to initiate the migration.

Once this contract is deployed, simply transfer ANTv1 into the contract as desired and then call migrate() to complete the upgrade.

The EscrowANTv2Migrator contract does not contain logic to return any ANTv1 tokens transferred to it. All ANTv1 tokens transferred to it will be eventually converted to ANTv2 and returned to the configured recipient.