Token Registry

Token Registry

This is a system smart contract which is publicly available for everyone to use.

The TokenRegistry contract will be used for displaying all the tokens available on aeternity blockchain with the relevant information - total_supply, balances, owners, meta_info, etc.

The waellet will be auto fetching the user balances without the need to manually entering the address for each contract.

Contract addresses

Note: Token registry contracts will be slightly modified and re-deployed after Lima protocol upgrade, for more efficiency. The state will be migrated and the new contract addresses will published here.

Network	Contract address
Mainnet	ct_UAzV9RcXEMsFcUCmrPN4iphbZroM7EHk3wvdidDYgZGGBo3hV
Testnet	ct_UAzV9RcXEMsFcUCmrPN4iphbZroM7EHk3wvdidDYgZGGBo3hV

The contract used in waellet is located at these addresses. We suggest other interfaces, decentralized applications, decentralized exchanges, and wallets use the same addresses in order to have an on-chain synced library of tokens without sacrificing user experience.

Adding token

If anyone wants to add a new token to the Token Registry contract, they should call add_token(token: Token) method, providing the AEX-9 (aeternity fungible token) token contract address (ex. ct_...).

Note: The caller will pay for the tx fees for storing the new address in the smart contract's state.

Contract interface and implementation

contract Token =
  record meta_info =
    { name : string
    , symbol : string
    , decimals : int }
    
  entrypoint meta_info : () => meta_info
  entrypoint total_supply : () => int
  entrypoint owner : () => address
  entrypoint balances : () => map(address, int)
  entrypoint balance : (address) => option(int)
  entrypoint transfer : (address, int) => ()

contract TokenRegistry =
  record state = { tokens: map(Token, Token.meta_info) }
 
  stateful entrypoint init() = { tokens = {} }
  
  stateful entrypoint add_token(token : Token) : () =
    put(state{ tokens[token] = token.meta_info() })

  entrypoint get_all_tokens() : map(Token, Token.meta_info) = state.tokens

  entrypoint get_token_meta_info(token : Token) : Token.meta_info = token.meta_info()
  entrypoint get_token_balances(token : Token) : map(address, int) = token.balances()
  entrypoint get_token_balance(token : Token, account: address) : option(int) = token.balance(account)
  entrypoint get_token_owner(token : Token) : address = token.owner()
  entrypoint get_token_total_supply(token : Token) : int = token.total_supply()

Source code: waellet/token-registry

Token registry migrator

contract Token =
  record meta_info =
    { name : string
    , symbol : string
    , decimals : int }
    
  entrypoint meta_info     : ()              => meta_info
  entrypoint total_supply  : ()              => int
  entrypoint owner         : ()              => address
  entrypoint balances      : ()              => map(address, int)
  entrypoint balance       : (address)       => option(int)
  entrypoint transfer      : (address, int)  => unit

contract TokenRegistry =
  entrypoint add_token              : (Token)           => unit
  entrypoint get_all_tokens         : ()                => map(Token, Token.meta_info)
  entrypoint get_token_meta_info    : (Token)           => Token.meta_info
  entrypoint get_token_balances     : (Token)           => map(address, int)
  entrypoint get_token_balance      : (Token, address)  => option(int)
  entrypoint get_token_owner        : (Token)           => address
  entrypoint get_token_total_supply : (Token)           => int
  
contract GetTokenRegistryState =
  entrypoint get_state(registry: TokenRegistry) : map(Token, Token.meta_info) = registry.get_all_tokens()