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Transaction

Icon LinkTransaction 

enum TransactionType : uint8 {
    Script = 0,
    Create = 1,
    Mint = 2,
}
nametypedescription
typeTransactionType Transaction type.
dataOne of TransactionScript , TransactionCreate , or TransactionMint Transaction data.
Transaction is invalid if:
  • type > TransactionType.Mint
  • inputsCount > MAX_INPUTS
  • outputsCount > MAX_OUTPUTS
  • witnessesCount > MAX_WITNESSES
  • size > MAX_TRANSACTION_SIZE. The size of a transaction is calculated as the sum of the sizes of its static and dynamic parts, as determined by canonical serialization.
  • No inputs are of type InputType.Coin or InputType.Message with input.dataLength == 0
  • More than one output is of type OutputType.Change for any asset ID in the input set
  • Any output is of type OutputType.Change for any asset ID not in the input set
  • More than one input of type InputType.Coin for any Coin ID in the input set
  • More than one input of type InputType.Contract for any Contract ID in the input set
  • More than one input of type InputType.Message for any Message ID in the input set
When serializing a transaction, fields are serialized as follows (with inner structs serialized recursively):
  1. uint8, uint16, uint32, uint64: big-endian right-aligned to 8 bytes.
  2. byte[32]: as-is.
  3. byte[]: as-is, with padding zeroes aligned to 8 bytes.
When deserializing a transaction, the reverse is done. If there are insufficient bytes or too many bytes, the transaction is invalid.

Icon LinkTransactionScript 

enum ReceiptType : uint8 {
    Call = 0,
    Return = 1,
    ReturnData = 2,
    Panic = 3,
    Revert = 4,
    Log = 5,
    LogData = 6,
    Transfer = 7,
    TransferOut = 8,
    ScriptResult = 9,
    MessageOut = 10,
    Mint = 11,
    Burn = 12,
}
nametypedescription
scriptGasLimituint64Gas limits the script execution.
scriptLengthuint16Script length, in instructions.
scriptDataLengthuint16Length of script input data, in bytes.
policyTypesuint32Bitfield of used policy types.
inputsCountuint8Number of inputs.
outputsCountuint8Number of outputs.
witnessesCountuint8Number of witnesses.
receiptsRootbyte[32]Merkle root of receipts.
scriptbyte[]Script to execute.
scriptDatabyte[]Script input data (parameters).
policiesPolicy []List of policies, sorted by PolicyType.
inputsInput []List of inputs.
outputsOutput []List of outputs.
witnessesWitness []List of witnesses.
Given helper max_gas() returns the maximum gas that the transaction can use. Given helper len() that returns the number of bytes of a field. Given helper count_ones() that returns the number of ones in the binary representation of a field. Given helper count_variants() that returns the number of variants in an enum. Given helper sum_variants() that sums all variants of an enum.
Transaction is invalid if:
  • More than one output is of type OutputType.Change with identical asset_id fields.
  • Any output is of type OutputType.ContractCreated
  • scriptLength > MAX_SCRIPT_LENGTH
  • scriptDataLength > MAX_SCRIPT_DATA_LENGTH
  • scriptLength * 4 != len(script)
  • scriptDataLength != len(scriptData)
  • max_gas(tx) > MAX_GAS_PER_TX
  • No policy of type PolicyType.GasPrice
  • count_ones(policyTypes) > count_variants(PolicyType)
  • policyTypes > sum_variants(PolicyType)
  • len(policies) > count_ones(policyTypes)
Icon InfoCircle
Note: when signing a transaction, receiptsRoot is set to zero.
Note: when verifying a predicate, receiptsRoot is initialized to zero.
Note: when executing a script, receiptsRoot is initialized to zero.
The receipts root receiptsRoot is the root of the binary Merkle tree of receipts. If there are no receipts, its value is set to the root of the empty tree, i.e. 0xe3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855.

Icon LinkTransactionCreate

nametypedescription
bytecodeLengthuint16Contract bytecode length, in instructions.
bytecodeWitnessIndexuint8Witness index of contract bytecode to create.
policyTypesuint32Bitfield of used policy types.
storageSlotsCountuint16Number of storage slots to initialize.
inputsCountuint8Number of inputs.
outputsCountuint8Number of outputs.
witnessesCountuint8Number of witnesses.
saltbyte[32]Salt.
policiesPolicy []List of policies.
storageSlots(byte[32], byte[32]])[]List of storage slots to initialize (key, value).
inputsInput []List of inputs.
outputsOutput []List of outputs.
witnessesWitness []List of witnesses.
Given helper max_gas() returns the maximum gas that the transaction can use. Given helper count_ones() that returns the number of ones in the binary representation of a field. Given helper count_variants() that returns the number of variants in an enum. Given helper sum_variants() that sums all variants of an enum.
Transaction is invalid if:
  • Any input is of type InputType.Contract or InputType.Message where input.dataLength > 0
  • Any output is of type OutputType.Contract or OutputType.Variable or OutputType.Message
  • More than one output is of type OutputType.Change with asset_id of zero
  • Any output is of type OutputType.Change with non-zero asset_id
  • It does not have exactly one output of type OutputType.ContractCreated
  • bytecodeLength * 4 > CONTRACT_MAX_SIZE
  • tx.data.witnesses[bytecodeWitnessIndex].dataLength != bytecodeLength * 4
  • bytecodeWitnessIndex >= tx.witnessesCount
  • The keys of storageSlots are not in ascending lexicographic order
  • The computed contract ID (see below) is not equal to the contractID of the one OutputType.ContractCreated output
  • storageSlotsCount > MAX_STORAGE_SLOTS
  • max_gas(tx) > MAX_GAS_PER_TX
  • The Sparse Merkle tree root of storageSlots is not equal to the stateRoot of the one OutputType.ContractCreated output
  • No policy of type PolicyType.GasPrice
  • count_ones(policyTypes) > count_variants(PolicyType)
  • policyTypes > sum_variants(PolicyType)
  • len(policies) > count_ones(policyTypes)
Creates a contract with contract ID as computed here .

Icon LinkTransactionMint

The transaction is created by the block producer and is not signed. Since it is not usable outside of block creation or execution, all fields must be fully set upon creation without any zeroing. This means that the transaction ID must also include the correct txPointer value, not zeroed out.
nametypedescription
txPointerTXPointer The location of the Mint transaction in the block.
inputContractInputContract The contract UTXO that assets are minted to.
outputContractOutputContract The contract UTXO that assets are being minted to.
mintAmountuint64The amount of funds minted.
mintAssetIdbyte[32]The asset IDs corresponding to the minted amount.
Transaction is invalid if:
  • txPointer is zero or doesn't match the block.
  • outputContract.inputIndex is not zero