Data Structure

Unichain is made up of blocks that are cryptography linked together. It looks like the following picture unichain data structure

UniChain data block structure

Block format

The data structure of each block will have the following format:

{ 
    blockID: '00000000003cc011a919fc5a51a5be8580ac7e1ff9e35786c75c954cdef5e519',
    block_header:{ 
        raw_data:{ 
            number: 3981329,
            txTrieRoot: '0f7f7af667b935544ba5a09d597a8f78738fe2b501a7f48ff35d06aeff10422f',
            witness_address: '44b198c855605d829bb418cd9696c9fd1a0b42ed79',
            parentHash: '00000000003cc010ce8b672ba201bd3bfb54f1b6ec4b036eb3a92bc33ad9dcd2',
            version: 1,
            timestamp: 1603210488000 
        },
        witness_signature:
        'f81fda75a3ed8e590c67815f4ba1af8c61be4240b90fb0029d35f0ae4b9799d44127aa5da76ed28c6394f3f4bbbfbbfabd78a7cb84ca56ff6994bb2f281764fa01' },
    transactions:[ 
        { 
            ret: [Array],
            signature: [Array],
            txID: 'aab2250cf3ca199f41c018a1fa89a31b05b6e2053290dd8d85778a9defc0bfc6',
            raw_data: [Object],
            raw_data_hex:
                '0a02c0102208ce8b672ba201bd3b40e88eaeb6d42e5a68080112640a2d747970652e676f6f676c65617069732e636f6d2f70726f746f636f6c2e5472616e73666572436f6e747261637412330a1544106a6917bbafb7e96861c97aa95e24bbaa8230ca12154478f2d8fc9a88eec78c1fd95873bd4b02177065cd1880ade2047096c9aab6d42e' 
        } 
    ] 
}

Where:

  • blockID: is the block hash
  • block_header: contains the raw_data (block number, witness address, tx root, parent hash, time stamp ...) and witness_signature who produces the block
  • transactions: the list of transaction in the block. Each transaction has the brief information that will be described below.

You can get the block by calling the full node API

curl -X POST ${node_endpoint}/wallet/getblockbynum -d '{"num":  block_numer}'

Or

curl -X POST ${node_endpoint}/wallet/getblockbyid -d '{"value":  "block_hash"}'

You can also try to get block information by calling the UniChainJS api

const block = await unichain.api.getBlockByNumber(blockNumber)
console.log('Block data:', block)

Try It yourself

Transaction format

The transaction will have the following structure:

{
    ret: [
        {
            contractRet: 'SUCCESS'
        }
    ],
    signature: [
        'a9fe1b28a35ffcb2cf6ed46f25926978f76df0ac166bf0c22e84db2e23d3a7b901d856582da97081ab3b1a2b7c97daaaa85f1ca760bb568d0c73a3bb30b4e8d701'
    ],
    txID: '232176ccd94b079bbc1afe8687f656a2708ee29e4aea254699f0323bbb8ab530',
    raw_data: {
        contract: [
            {
                parameter: {
                    value: {
                        amount: 1000000,
                        owner_address: '4478f2d8fc9a88eec78c1fd95873bd4b02177065cd',
                        to_address: '440bc353c683213030a0525cb76169442d3c729f01'
                    },
                    type_url: 'type.googleapis.com/protocol.TransferContract'
                },
                type: 'TransferContract'
            }
        ],
        ref_block_bytes: 'c0f3',
        ref_block_hash: '9af2438cd42944e7',
        expiration: 1603211226000,
        timestamp: 1603211167488
    },
    raw_data_hex: '0a02c0f322089af2438cd42944e74090d7d7b6d42e5a67080112630a2d747970652e676f6f676c65617069732e636f6d2f70726f746f636f6c2e5472616e73666572436f6e747261637412320a154478f2d8fc9a88eec78c1fd95873bd4b02177065cd1215440bc353c683213030a0525cb76169442d3c729f0118c0843d70808ed4b6d42e'
}

Where:

  • ret: Contains the list of status. Normally the ret[0] indicates the status of transction. If ret[0].contractRet equal to SUCCESS then the transaction is successful. Otherwise it will fail with many status such as: REVERT, STACK_OVERFLOW, OUT_OF_MEMORY ...
  • signature: The list of sender's signatures. There will be more than one signature in case of multisign
  • raw_data: raw data of the transaction.
    • contract: the list of contract but normally, get the first from the list (contract[0]). Depending on each type of contract, there will be different parameters. For example, the TransferContract above will have the parameter.value: amount - The amount of UNW to be transferred in Ginza unit (1 UNW = 10^6 Ginza), owner_address the sender’s address in hex format, to_address: the receiver’s address in hex format. You can check all the input parameters of any contract in the protobuf specs here
    • ref_block_bytes and ref_block_hash: The height and the hash of the transaction reference block, using the 6th to 8th (exclusive) bytes of the reference block height, a total of 2 bytes. The reference block is used in the UNI TAPOS mechanism, which can prevent a replay of a transaction on forks that do not include the referenced block. Generally the latest solidified block is used as the reference block
    • expiration: Transaction expiration time, beyond which the transaction will no longer be packed. The default value from full node is 60 seconds but It can be configured to be a maximum of 24 hours.
    • timestamp: The Timestamp of transaction creation
  • raw_data_hex: The raw data in hex format

You can get transaction data by calling the full node API or UniChainJS API

curl -X POST  http://{host}/wallet/gettransactionbyid -d '{"value": "transaction_hash"}'

const txid = 'transaction_hash'
const tx = await unichain.api.getTransaction(txid)
console.log('Transaction: ', tx)

Please note that the transaction and block will be finalized after ⅔ of the witness confirmation (more than 22 blocks and about 1 minute). For the applications that need more reliability, please get the transaction and block in the relay/solidity node. For example:

curl -X POST  http://{host}/walletsolidity/gettransactionbyid -d '{"value": "transaction_hash"}'

Try It yourself

Related resources:

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