extension-node

[TOC]

api

1. getTokenAllowance

Returns the amount which the spender is allowed to withdraw from the owner.

• Parameters:

  • contract - The address of the token contract.
  • owner - The address of the token owner.
  • spender - The address of the token spender.

{
    "jsonrpc":"2.0",
    "method":"getTokenAllowance",
    "params":[
        {
            "contract":"0x038da599a137f89f49b43cd0d561d5e159058b60",
            "owner":"0x4a555dfda69bd6b44b941fb5eca0a3b40de9626b",
            "spender":"0x8d12a197cb00d4747a1fe03395095ce2a5cc6819"
        }
    ],
    "id":1
}

• Returns:
  • result - The allowance amount.

{
  "jsonrpc": "2.0",
  "id": 83,
  "result": "10963536149943846000",
}

• flow

  ContractSlotInfo(contract)

  Keccak256Hash(slot, owner)

  Keccak256Hash(spender, ⬆️)

  GetStat(:arrow_up:)

2. getTokenBalances

Returns token balances for a specific address given a list of contracts. This method returns hex encoded values in the tokenBalance fields.

• Parameters
  • DATA, 20 Bytes - The address for which token balances will be checked
  • One of:
    1. Array - A list of contract addresses
    2. The String"DEFAULT_TOKENS" - denotes a query for the top 100 tokens by 24 hour volume

{
    "jsonrpc":"2.0",
    "method":"getTokenBalances",
    "params":[
        "0x10655cf97f07c6c0d746836ede834c53c808a0e9",
        [
            "0xe3818504c1b32bf1557b16c238b2e01fd3149c17"
        ]
    ]
    "id":"42"
}

• Returns
  • address: DATA, 20 Bytes - The address for which token balances were checked
  • tokenBalances: Array - returns an array of token balance objects. Each object contains:
    • contractAddress
    • tokenBalance
    • error
    • One of tokenBalance or error will be null.

{
  "jsonrpc":"2.0",
  "id":42,
  "result": {
    "address": "0x3f5ce5fbfe3e9af3971dd833d26ba9b5c936f0be"},
    "tokenBalances": [{"contractAddress": "0x607f4c5bb672230e8672085532f7e901544a7375", "tokenBalance": "0x00000000000000000000000000000000000000000000000000044d06e87e858e", "error": null}, {"contractAddress": "0x618e75ac90b12c6049ba3b27f5d5f8651b0037f6", "tokenBalance": "0x0000000000000000000000000000000000000000000000000000000000000000", "error": null}, {"contractAddress": "0x63b992e6246d88f07fc35a056d2c365e6d441a3d", "tokenBalance": "0x0000000000000000000000000000000000000000000000000000000000000000", "error": null}, {"contractAddress": "0x6467882316dc6e206feef05fba6deaa69277f155", "tokenBalance": "0x0000000000000000000000000000000000000000000000000000000000000000", "error": null}, {"contractAddress": "0x647f274b3a7248d6cf51b35f08e7e7fd6edfb271", "tokenBalance": "0x0000000000000000000000000000000000000000000000000000000000000000", "error": null}]
}

3. getTokenMetadata

Returns metadata (name, symbol, decimals, logo) for a given token contract address. name ,symbolanddecimalsare optional methods in the ERC-20 token standard. Therefore, not all contracts will respond correctly to calls requesting this information. While the incorrectness or absence ofname and symbolcan be an inconvenience, having the correct decimalsis absolutely crucial in displaying token balances or converting user inputs accurately when communicating with the contract. Alchemy maintains a regularly updated database of contract metadata, with values gathered and intelligently merged from the contracts themselves along with several other sources. Alchemy is therefore able to provide clean, accurate, up-to-date metadata for contracts that may be missing any of these methods or have changed their name or symbol since contract publication. As a bonus, token logo images are available for many of the popular tokens.

• Parameters
  • DATA, 20 Bytes - The address of the token contract.

{
    "jsonrpc":"2.0",
    "method":"alchemy_getTokenMetadata",
    "params":[
        "0x1985365e9f78359a9B6AD760e32412f4a445E862"
    ],
    "id":1
}

• Returns
  • Object - An object with the following fields:
    • name: String - The token's name. null if not defined in the contract and not available from other sources.
    • symbol: String - The token's symbol. null if not defined in the contract and not available from other sources.
    • decimals: Number - The number of decimals of the token. null if not defined in the contract and not available from other sources.
    • logo: String - URL of the token's logo image. null if not available.

{
  "jsonrpc": "2.0",
  "id": 1,
  "result": {
    "logo": "https://static.alchemyapi.io/images/assets/1104.png",
    "symbol": "REP",
    "decimals": 18,
    "name": "Augur"
  }
}

ContractSlotInfo(contractAddress, name[name])->slot[name]

ContractState(address, slot[name])->value

ContractSlotInfo(contractAddress, name[decimals])->slot[decimals]

ContractState(address, slot[decimals])->value

ContractSlotInfo(contractAddress, name[symbol])->slot[symbol]

ContractState(address, slot[symbol])->value

系统环境

工具	git
goframe	https://github.com/gogf/gf.git
qmgo	https://github.com/qiniu/qmgo.git
go-web3	https://github.com/umbracle/go-web3.git