Token Transfer
Last updated
Last updated
Acala supports different types of tokens than Polkadot, and allows various ways to transfer tokens. This guide will walk through tokens available on Acala, tools can be used for transfers, how to send transfer transactions, monitor and track these transactions.
| Symbol | Description | CurrencyId | Decimals | Minimal Balance |
|---|---|---|---|---|
aUSD is converted to aSEED on July 20 2023
AssetRegistry registered the metadata info of this type token.
The lp share token for the trading pair of Acala DEX. The CurrencyId type of Acala DEX's lp token are CurrencyId::DexShare, and the decimals and minimal balance of lp token are same as the first token in DexShare. For example, CurrencyId::DexShare(Token(ACA), Token(AUSD)) is the CurrencyId of lp token of ACA/aSEED pair, its decimal is 12, and minimal balance is 0.1, these are same as ACA.
Currently, AssetRegistry does not register metadata info of any lp token.
Token issued by ERC20 contracts deployed in Acala EVM+. The CurrencyId type is Erc20(Address), Address is the ERC20 contract address on EVM+.
AssetRegistry registered the metadata info of this type token.
Tokens originated from other parachains.
AssetRegistry registered the metadata info of this type token.
JS/TS SDK: https://github.com/AcalaNetwork/acala.js
Blockchain explorer: http://acala.subscan.io
api-sidecar: https://github.com/paritytech/substrate-api-sidecar
txwrapper: https://github.com/AcalaNetwork/txwrapper
Query chain state to get token balances.
Query system module to get native token (ACA) balances data.
Returns the AccountInfo of given account. For different types of balances, check the fields in AccountInfo.data
free: the free balance.
reserve: the reserved balance.
For non-native tokens, like DOT, LDOT, aUSD, query tokens module to get balances info.
Returns the OrmlAccountData of given account and currency ID. For different types of balances, check the fields:
free: the free balance.
reserved: the reserved balance.
Returns the BalanceLock of given account and currency ID. BalanceLock has two fields:
id: the lock identifier.
amount. the locked amount.
Note locks could be overlapped, and the same amount of tokens could be under locked by multiple locks.
This can be used to send any supported tokens in the network, including ACA, DOT, LDOT, LCDOT, aUSD etc.
This can be used to send native token (ACA). It has slightly cheaper transaction fees compare to currencies.transfer
Same as currencies.transferNativeCurrency, only for native token (ACA).
Compatible with Polkadot / Polkadot and most other Substrate-based chains.
ORML's Xtokens Module supports token transfer by cross-consensus messages (XCM), and has a number of dispatchable functions to support different use cases.
xtokens transfer functions: xtokens.transfer xtokens.transfer_multiasset xtokens.transfer_with_fee
xtokens.transfer_multiasset_with_fee
xtokens.transfer_multicurrencies
xtokens.transfer_multiassets
Can be used to send any supported tokens in the source and destination networks, including ERC20 tokens.
There are multiple ways to detect incoming balance transfers:
Monitor events
Subscribe storage changes
Monitor transactions
Monitoring events is a recommended way to track incoming balance transfers. It can handle ALL types of transfer transactions including the one that is not initiated by a transaction directly (e.g. delayed proxy).
Emitted when a native token (ACA) transfer happened.
Emitted when a token transfer happened.
NOTE: This is not emitted when balances.transfer is used to make a transfer.
Emitted when a token is minted to an account. This could happen when it is a cross-chain transfer or it is a transaction minting stablecoins.
For cross-chain transfer, there would be ExecutedDownward event along with the deposit. https://acala.subscan.io/event?address=&module=dmpqueue&event=executeddownward
Emitted when a cross-chain transfer happened from Karura to other chains.
Triggered byxtokens.transfer, xtokens.transfer_multiasset, xtokens.transfer_with_fee, xtokens.transfer_multiasset_with_fee, xtokens.transfer_multicurrencies, xtokens.transfer_multiassets extrinsics .
Subscribe to a list of account balances. However, it does not guarantee subscription delivery due to connection errors or blockchain reorg.
It is possible to fetch transactions in every block, check for transfer transactions, and check if the transfer transaction is successful. However, this may likely yield false-negative results i.e. deposit received but failed to recognize, due to the various ways for transfer.
Refer to Send Tokens section for direct transfer transactions. In additional, to sending transfer transactions individually, there are common utility methods to batch send transfer transactions:
This can be used to send batch transaction
NOTE: batched transactions will always emit success events.
utility.BatchCompleted event indicates that all transactions are successful
utility.BatchInterrupted event indicates which transaction failed. Transactions before the failed transaction are executed successfully and will not be reverted.
This is similar to utility.batch but will revert all transactions upon failed transaction.
| Symbol | Description | CurrencyId | Decimals | Minimal Balance |
|---|---|---|---|---|
ACA
native token of Acala network
Token(ACA)
12
0.1 ACA
aSEED
multi-collateralized stablecoin
Token(AUSD)
12
0.1 aUSD
DOT
crossed to Acala from Polkadot Relay Chain
Token(DOT)
10
0.01 DOT
LDOT
tokenized staked DOT from the Liquid Staking protocol
Token(LDOT)
10
0.05 LDOT
LcDOT
tokenized liquid receipt of crowdloaned DOT
LiquidCrowdloan(13)
10
0.01 LcDOT
