Transaction

@opcat-labs/scrypt-ts-opcat / Transaction

Class: Transaction

Defined in: node_modules/@opcat-labs/opcat/types/transaction/transaction.d.cts:12

Represents a transaction, a set of inputs and outputs to change ownership of tokens

Param

Optional serialized data to initialize the transaction. Can be a hex string, Buffer, plain object, or another Transaction instance.

Throws

If invalid serialization format is provided.

Constructors

new Transaction()

new Transaction(serialized?): Transaction

Defined in: node_modules/@opcat-labs/opcat/types/transaction/transaction.d.cts:24

Represents a transaction, a set of inputs and outputs to change ownership of tokens

Parameters

serialized?

any

Optional serialized data to initialize the transaction. Can be a hex string, Buffer, plain object, or another Transaction instance.

Returns

Transaction

Throws

If invalid serialization format is provided.

Properties

_changeAddress

_changeAddress: any

Defined in: node_modules/@opcat-labs/opcat/types/transaction/transaction.d.cts:165

_changeData

_changeData: any

Defined in: node_modules/@opcat-labs/opcat/types/transaction/transaction.d.cts:166

_changeIndex

_changeIndex: any

Defined in: node_modules/@opcat-labs/opcat/types/transaction/transaction.d.cts:163

_changeScript

_changeScript: Script

Defined in: node_modules/@opcat-labs/opcat/types/transaction/transaction.d.cts:164

_fee

_fee: any

Defined in: node_modules/@opcat-labs/opcat/types/transaction/transaction.d.cts:167

_feePerKb

_feePerKb: number

Defined in: node_modules/@opcat-labs/opcat/types/transaction/transaction.d.cts:294

_inputAmount

_inputAmount: number

Defined in: node_modules/@opcat-labs/opcat/types/transaction/transaction.d.cts:27

_inputsMap

_inputsMap: Map\<any, any>

Defined in: node_modules/@opcat-labs/opcat/types/transaction/transaction.d.cts:29

_outputAmount

_outputAmount: number

Defined in: node_modules/@opcat-labs/opcat/types/transaction/transaction.d.cts:28

_outputsMap

_outputsMap: Map\<any, any>

Defined in: node_modules/@opcat-labs/opcat/types/transaction/transaction.d.cts:30

_privateKey

_privateKey: Buffer | Buffer[]

Defined in: node_modules/@opcat-labs/opcat/types/transaction/transaction.d.cts:31

_sigType

_sigType: number

Defined in: node_modules/@opcat-labs/opcat/types/transaction/transaction.d.cts:32

hash

readonly hash: any

Defined in: node_modules/@opcat-labs/opcat/types/transaction/transaction.d.cts:34

id

readonly id: any

Defined in: node_modules/@opcat-labs/opcat/types/transaction/transaction.d.cts:35

inputs

inputs: any[]

Defined in: node_modules/@opcat-labs/opcat/types/transaction/transaction.d.cts:25

Transaction input objects.

nLockTime

nLockTime: any

Defined in: node_modules/@opcat-labs/opcat/types/transaction/transaction.d.cts:145

outputs

outputs: any[]

Defined in: node_modules/@opcat-labs/opcat/types/transaction/transaction.d.cts:26

Transaction output objects.

sealed

sealed: boolean

Defined in: node_modules/@opcat-labs/opcat/types/transaction/transaction.d.cts:33

Indicates if transaction is finalized.

toObject()

toObject: () => any

Defined in: node_modules/@opcat-labs/opcat/types/transaction/transaction.d.cts:152

Converts the Transaction object to a plain JavaScript object (POJO) for serialization. Includes transaction details like hash, version, inputs, outputs, and lock time. Optionally includes change script, change address, change index, and fee if they are defined.

Returns

any

A plain object representation of the transaction.

toString()

toString: () => string

Defined in: node_modules/@opcat-labs/opcat/types/transaction/transaction.d.cts:64

Returns

string

uncheckedSerialize()

uncheckedSerialize: () => string

Defined in: node_modules/@opcat-labs/opcat/types/transaction/transaction.d.cts:63

Serializes the transaction to a hexadecimal string. This method is aliased as toString() and toHex() for convenience.

Returns

string

Hexadecimal representation of the transaction.

version

version: any

Defined in: node_modules/@opcat-labs/opcat/types/transaction/transaction.d.cts:144

Accessors

inputAmount

Get Signature

get inputAmount(): number

Defined in: node_modules/@opcat-labs/opcat/types/transaction/transaction.d.cts:36

Returns

number

outputAmount

Get Signature

get outputAmount(): number

Defined in: node_modules/@opcat-labs/opcat/types/transaction/transaction.d.cts:37

Returns

number

Methods

_isMissingSignatures()

_isMissingSignatures(opts): any

Defined in: node_modules/@opcat-labs/opcat/types/transaction/transaction.d.cts:96

Checks if the transaction is missing signatures.

Parameters

opts

Options object.

disableIsFullySigned?

boolean

If true, skips the check.

Returns

any

Returns MissingSignatures error if not fully signed, otherwise undefined.

addData()

addData(value): Transaction

Defined in: node_modules/@opcat-labs/opcat/types/transaction/transaction.d.cts:337

Add an OP_RETURN output to the transaction.

Beware that this resets all the signatures for inputs (in further versions, SIGHASH_SINGLE or SIGHASH_NONE signatures will not be reset).

Parameters

value

the data to be stored in the OP_RETURN output. In case of a string, the UTF-8 representation will be stored

string | Buffer

Returns

Transaction

this, for chaining

addDummyInput()

addDummyInput(script, satoshis): Transaction

Defined in: node_modules/@opcat-labs/opcat/types/transaction/transaction.d.cts:624

Adds a dummy input to the transaction with the specified script and satoshis. The dummy input uses a placeholder script and a fixed previous transaction ID.

Parameters

script

Script

The script to use for the output of the dummy input.

satoshis

number

The amount in satoshis for the output of the dummy input.

Returns

Transaction

The transaction instance for chaining.

addInput()

addInput(input, outputScript?, satoshis?, data?): Transaction

Defined in: node_modules/@opcat-labs/opcat/types/transaction/transaction.d.cts:261

Add an input to this transaction. The input must be an instance of the Input class. It should have information about the Output that it's spending, but if it's not already set, three additional parameters, outputScript, satoshis and data can be provided.

Parameters

input

Input

The input to add

outputScript?

The output script (required if input doesn't have output)

string | Script

satoshis?

number

The satoshis amount (required if input doesn't have output)

data?

Additional data for the output

string | Buffer

Returns

Transaction

The transaction instance for chaining

Throws

If input has no output and missing required params

addInputFromPrevTx()

addInputFromPrevTx(prevTx, outputIndex?): Transaction

Defined in: node_modules/@opcat-labs/opcat/types/transaction/transaction.d.cts:615

Adds an input to the transaction from a previous transaction's output.

Parameters

prevTx

Transaction

The previous transaction containing the output to spend.

outputIndex?

number

The index of the output in the previous transaction.

Returns

Transaction

The transaction instance for chaining.

Throws

If prevTx is not a valid Transaction.

addOutput()

addOutput(output): Transaction

Defined in: node_modules/@opcat-labs/opcat/types/transaction/transaction.d.cts:355

Add an output to the transaction.

Parameters

output

Output

the output to add.

Returns

Transaction

this, for chaining

addSafeData()

addSafeData(value): Transaction

Defined in: node_modules/@opcat-labs/opcat/types/transaction/transaction.d.cts:348

Add an OP_FALSE | OP_RETURN output to the transaction.

Beware that this resets all the signatures for inputs (in further versions, SIGHASH_SINGLE or SIGHASH_NONE signatures will not be reset).

Parameters

value

the data to be stored in the OP_RETURN output. In case of a string, the UTF-8 representation will be stored

string | Buffer

Returns

Transaction

this, for chaining

applySignature()

applySignature(signature): Transaction

Defined in: node_modules/@opcat-labs/opcat/types/transaction/transaction.d.cts:473

Add a signature to the transaction

Parameters

signature

inputIndex

number

publicKey

PublicKey

signature

Signature

sigtype

number

Returns

Transaction

this, for chaining

change()

change(address, data): Transaction

Defined in: node_modules/@opcat-labs/opcat/types/transaction/transaction.d.cts:305

Set the change address for this transaction

Beware that this resets all the signatures for inputs (in further versions, SIGHASH_SINGLE or SIGHASH_NONE signatures will not be reset).

Parameters

address

Address

An address for change to be sent to.

data

The data to be stored in the change output.

string | Buffer

Returns

Transaction

this, for chaining

checkedSerialize()

checkedSerialize(opts): string

Defined in: node_modules/@opcat-labs/opcat/types/transaction/transaction.d.cts:73

Retrieve a hexa string that can be used with bitcoind's CLI interface (decoderawtransaction, sendrawtransaction)

Parameters

opts

any

allows to skip certain tests. {@see Transaction#serialize}

Returns

string

checkFeeRate()

checkFeeRate(feePerKb?): boolean

Defined in: node_modules/@opcat-labs/opcat/types/transaction/transaction.d.cts:581

Checks if the transaction's fee rate meets or exceeds the expected rate.

Parameters

feePerKb?

number

Optional fee per KB (in satoshis). Falls back to instance or default fee.

Returns

boolean

True if actual fee rate (fee/size) >= expected rate.

clearOutputs()

clearOutputs(): Transaction

Defined in: node_modules/@opcat-labs/opcat/types/transaction/transaction.d.cts:361

Remove all outputs from the transaction.

Returns

Transaction

this, for chaining

clone()

clone(): Transaction

Defined in: node_modules/@opcat-labs/opcat/types/transaction/transaction.d.cts:57

Creates a deep clone of the Transaction instance.

Returns

Transaction

A new Transaction instance with cloned inputs.

dummyChange()

dummyChange(): Transaction

Defined in: node_modules/@opcat-labs/opcat/types/transaction/transaction.d.cts:633

Same as change(addresss), but using the address of Transaction.DUMMY_PRIVATEKEY as default change address

Beware that this resets all the signatures for inputs (in further versions, SIGHASH_SINGLE or SIGHASH_NONE signatures will not be reset).

Returns

Transaction

this, for chaining

fee()

fee(amount): Transaction

Defined in: node_modules/@opcat-labs/opcat/types/transaction/transaction.d.cts:284

Manually set the fee for this transaction. Beware that this resets all the signatures for inputs (in further versions, SIGHASH_SINGLE or SIGHASH_NONE signatures will not be reset).

Parameters

amount

number

satoshis to be sent

Returns

Transaction

this, for chaining

feePerKb()

feePerKb(amount): Transaction

Defined in: node_modules/@opcat-labs/opcat/types/transaction/transaction.d.cts:293

Manually set the fee per KB for this transaction. Beware that this resets all the signatures for inputs (in further versions, SIGHASH_SINGLE or SIGHASH_NONE signatures will not be reset).

Parameters

amount

number

satoshis per KB to be sent

Returns

Transaction

this, for chaining

from()

from(utxo): Transaction

Defined in: node_modules/@opcat-labs/opcat/types/transaction/transaction.d.cts:248

Add an input to this transaction. This is a high level interface to add an input, for more control, use @{link Transaction#addInput}.

Can receive, as output information, the output of bitcoind's listunspent command, and a slightly fancier format recognized by opcat:

{
 address: 'mszYqVnqKoQx4jcTdJXxwKAissE3Jbrrc1',
 txId: 'a477af6b2667c29670467e4e0728b685ee07b240235771862318e29ddbe58458',
 outputIndex: 0,
 script: Script.empty(),
 satoshis: 1020000
}

Where address can be either a string or a opcat Address object. The same is true for script, which can be a string or a opcat Script.

Beware that this resets all the signatures for inputs (in further versions, SIGHASH_SINGLE or SIGHASH_NONE signatures will not be reset).

Parameters

utxo

any

Returns

Transaction

The transaction instance for chaining.

Example

var transaction = new Transaction();

// From a pay to public key hash output from bitcoind's listunspent
transaction.from({'txid': '0000...', vout: 0, amount: 0.1, scriptPubKey: 'OP_DUP ...'});

// From a pay to public key hash output
transaction.from({'txId': '0000...', outputIndex: 0, satoshis: 1000, script: 'OP_DUP ...'});

fromBuffer()

fromBuffer(buffer): Transaction

Defined in: node_modules/@opcat-labs/opcat/types/transaction/transaction.d.cts:136

Initializes the transaction from a buffer.

Parameters

buffer

Buffer

The buffer containing transaction data.

Returns

Transaction

The transaction instance.

fromBufferReader()

fromBufferReader(reader): Transaction

Defined in: node_modules/@opcat-labs/opcat/types/transaction/transaction.d.cts:143

Reads transaction data from a buffer reader and populates the transaction instance.

Parameters

reader

BufferReader

The buffer reader containing transaction data.

Returns

Transaction

The transaction instance with populated data.

Throws

If no transaction data is received (reader is finished).

fromObject()

fromObject(arg): Transaction

Defined in: node_modules/@opcat-labs/opcat/types/transaction/transaction.d.cts:162

Creates a Transaction instance from a plain object or another Transaction. Handles conversion of inputs/outputs and other transaction properties.

Parameters

arg

any

Either a transaction object or Transaction instance

Returns

Transaction

The populated Transaction instance

Throws

If argument is not an object or Transaction instance

fromString()

fromString(string): Transaction

Defined in: node_modules/@opcat-labs/opcat/types/transaction/transaction.d.cts:200

Converts a hex string into a transaction buffer and initializes the transaction.

Parameters

string

string

Hex string representation of the transaction data.

Returns

Transaction

The transaction instance initialized from the hex string.

getChangeAddress()

getChangeAddress(): Address

Defined in: node_modules/@opcat-labs/opcat/types/transaction/transaction.d.cts:315

Gets the change address for this transaction.

Returns

Address

The change address if set, otherwise null.

getChangeAmount()

getChangeAmount(): number

Defined in: node_modules/@opcat-labs/opcat/types/transaction/transaction.d.cts:570

Gets the amount of change (in satoshis) for this transaction.

Returns

number

The change amount in satoshis, or 0 if no change exists.

getChangeOutput()

getChangeOutput(): Output

Defined in: node_modules/@opcat-labs/opcat/types/transaction/transaction.d.cts:310

Gets the change output from the transaction outputs.

Returns

Output

The change output object if defined, otherwise null.

getEstimateFee()

getEstimateFee(): number

Defined in: node_modules/@opcat-labs/opcat/types/transaction/transaction.d.cts:575

Gets the estimated fee for the transaction.

Returns

number

The estimated fee value.

getEstimateSize()

getEstimateSize(): number

Defined in: node_modules/@opcat-labs/opcat/types/transaction/transaction.d.cts:396

Gets the estimated size of the transaction.

Returns

number

The estimated size in bytes.

getFee()

getFee(): number

Defined in: node_modules/@opcat-labs/opcat/types/transaction/transaction.d.cts:384

Calculates the fee of the transaction.

If there's a fixed fee set, return that.

If there is no change output set, the fee is the total value of the outputs minus inputs. Note that a serialized transaction only specifies the value of its outputs. (The value of inputs are recorded in the previous transaction outputs being spent.) This method therefore raises a "MissingPreviousOutput" error when called on a serialized transaction.

If there's no fee set and no change address, estimate the fee based on size.

Returns

number

fee of this transaction in satoshis

getInputAmount()

getInputAmount(inputIndex): number

Defined in: node_modules/@opcat-labs/opcat/types/transaction/transaction.d.cts:653

Gets the amount of satoshis for a specific transaction input.

Parameters

inputIndex

number

The index of the input to query.

Returns

number

The satoshis amount of the specified input.

Throws

If the input at the specified index doesn't exist.

getLockTime()

getLockTime(): number | Date

Defined in: node_modules/@opcat-labs/opcat/types/transaction/transaction.d.cts:194

Returns a semantic version of the transaction's nLockTime.

Returns

number | Date

If nLockTime is 0, it returns null, if it is < 500000000, it returns a block height (number) else it returns a Date object.

getOutputAmount()

getOutputAmount(outputIndex): number

Defined in: node_modules/@opcat-labs/opcat/types/transaction/transaction.d.cts:660

Gets the output amount in satoshis for the specified output index.

Parameters

outputIndex

number

The index of the output to retrieve.

Returns

number

The output amount in satoshis.

Throws

If the output index is invalid.

getPreimage()

getPreimage(inputIndex, sigtype?, isLowS?): Buffer

Defined in: node_modules/@opcat-labs/opcat/types/transaction/transaction.d.cts:599

Gets the preimage for a transaction input.

Parameters

inputIndex

number

The index of the input to get the preimage for.

sigtype?

number

The signature hash type.

isLowS?

boolean

Whether to use low-S signatures.

Returns

Buffer

The preimage for the specified input.

getSerializationError()

getSerializationError(opts): Error

Defined in: node_modules/@opcat-labs/opcat/types/transaction/transaction.d.cts:86

Retrieve a possible error that could appear when trying to serialize and broadcast this transaction.

Parameters

opts

any

allows to skip certain tests. {@see Transaction#serialize}

Returns

Error

getSignature()

getSignature(inputIndex, privateKeys?, sigtypes?): string | any[]

Defined in: node_modules/@opcat-labs/opcat/types/transaction/transaction.d.cts:607

Gets the signature(s) for a transaction input.

Parameters

inputIndex

number

Index of the input to sign.

privateKeys?

Private key(s) to sign with. Defaults to input's privateKey or transaction's _privateKey.

string | any[] | Buffer

sigtypes?

number

Signature hash type. Defaults to SIGHASH_ALL.

Returns

string | any[]

Single signature hex string or array of signatures. Returns empty array if no privateKeys provided.

getSignatures()

getSignatures(privKey, sigtype?): any[]

Defined in: node_modules/@opcat-labs/opcat/types/transaction/transaction.d.cts:462

Generates signatures for all inputs in the transaction using the provided private key.

Parameters

privKey

The private key to sign with (can be string or PrivateKey instance).

string | PrivateKey

sigtype?

number

The signature hash type (defaults to SIGHASH_ALL).

Returns

any[]

Array of generated signatures for the transaction inputs.

getUnspentValue()

getUnspentValue(): number

Defined in: node_modules/@opcat-labs/opcat/types/transaction/transaction.d.cts:390

Calculates the unspent value (difference between input and output amounts) of the transaction.

Returns

number

The unspent value (input amount minus output amount).

hasAllUtxoInfo()

hasAllUtxoInfo(): boolean

Defined in: node_modules/@opcat-labs/opcat/types/transaction/transaction.d.cts:275

Returns true if the transaction has enough info on all inputs to be correctly validated

Returns

boolean

hashForSignature()

hashForSignature(inputIndex, hashType): Buffer

Defined in: node_modules/@opcat-labs/opcat/types/transaction/transaction.d.cts:118

Calculates the double SHA-256 hash of the transaction preimage for signature verification. The resulting hash is returned in reverse byte order (little-endian).

Parameters

inputIndex

number

Index of the input being signed

hashType

number

SIGHASH type flag

Returns

Buffer

The hash result in little-endian format

inspect()

inspect(): string

Defined in: node_modules/@opcat-labs/opcat/types/transaction/transaction.d.cts:104

Returns a string representation of the Transaction object for debugging/inspection. The format is: '<Transaction: [serializedData]>' where serializedData comes from uncheckedSerialize().

Returns

string

Formatted transaction inspection string.

invalidSatoshis()

invalidSatoshis(): boolean

Defined in: node_modules/@opcat-labs/opcat/types/transaction/transaction.d.cts:78

Checks if any output in the transaction has invalid satoshis.

Returns

boolean

True if at least one output has invalid satoshis, false otherwise.

isCoinbase()

isCoinbase(): boolean

Defined in: node_modules/@opcat-labs/opcat/types/transaction/transaction.d.cts:522

Checks if the transaction is a coinbase transaction. A coinbase transaction has exactly one input and that input is null.

Returns

boolean

True if the transaction is a coinbase, false otherwise.

isFullySigned()

isFullySigned(): boolean

Defined in: node_modules/@opcat-labs/opcat/types/transaction/transaction.d.cts:485

Checks if all inputs in the transaction are fully signed.

Returns

boolean

True if all inputs have valid signatures, false otherwise.

Throws

If any input has an unrecognized script kind or insufficient information to verify signatures (common when deserializing transactions).

isSealed()

isSealed(): boolean

Defined in: node_modules/@opcat-labs/opcat/types/transaction/transaction.d.cts:591

Checks if the transaction is sealed.

Returns

boolean

True if the transaction is sealed, false otherwise.

isValidSignature()

isValidSignature(signature): boolean

Defined in: node_modules/@opcat-labs/opcat/types/transaction/transaction.d.cts:492

Validates a signature for a transaction input.

Parameters

signature

any

The signature object to validate.

Returns

boolean

True if the signature is valid for the specified input.

Throws

If the input script is unrecognized or lacks execution info.

lockUntilBlockHeight()

lockUntilBlockHeight(height): Transaction

Defined in: node_modules/@opcat-labs/opcat/types/transaction/transaction.d.cts:186

Sets the transaction's lock time to a specific block height. Validates the height is within allowed bounds (0 <= height < NLOCKTIME_BLOCKHEIGHT_LIMIT). Updates sequence numbers of inputs to enable lock time if using default sequence.

Parameters

height

number

The block height to lock until (must be non-negative and below limit)

Returns

Transaction

Returns the transaction instance for chaining

Throws

If height exceeds block height limit

Throws

If height is negative

lockUntilDate()

lockUntilDate(time): Transaction

Defined in: node_modules/@opcat-labs/opcat/types/transaction/transaction.d.cts:176

Sets nLockTime so that transaction is not valid until the desired date(a timestamp in seconds since UNIX epoch is also accepted)

Parameters

time

The lock time as a timestamp (number) or Date object.

number | Date

Returns

Transaction

The transaction instance for chaining.

Throws

If the time is a number below NLOCKTIME_BLOCKHEIGHT_LIMIT.

prevouts()

prevouts(): string

Defined in: node_modules/@opcat-labs/opcat/types/transaction/transaction.d.cts:586

Serializes the transaction's inputs (prevTxId and outputIndex) into a hex string.

Returns

string

Hex-encoded serialized input data.

removeInput()

removeInput(txId, outputIndex?): void

Defined in: node_modules/@opcat-labs/opcat/types/transaction/transaction.d.cts:444

Removes an input from the transaction by either its index or txId/outputIndex pair.

Parameters

txId

Transaction ID (as hex string) or input index if outputIndex is omitted.

string | number

outputIndex?

number

Output index of the input to remove (required if txId is string).

Returns

void

Throws

If input index is out of bounds.

removeOutput()

removeOutput(index): void

Defined in: node_modules/@opcat-labs/opcat/types/transaction/transaction.d.cts:403

Removes an output from the transaction at the specified index and updates the change output.

Parameters

index

number

The index of the output to remove.

Returns

void

seal()

seal(): Transaction

Defined in: node_modules/@opcat-labs/opcat/types/transaction/transaction.d.cts:559

Seals the transaction by processing all outputs and inputs.

For each output, executes the registered callback to generate the final output.
Updates the change output if applicable.
For each input, generates and sets the unlock script using the registered callback.
If a private key is provided, signs the transaction.
Marks the transaction as sealed and returns the instance.

Returns

Transaction

The sealed transaction instance.

serialize()

serialize(unsafe?): string

Defined in: node_modules/@opcat-labs/opcat/types/transaction/transaction.d.cts:52

Retrieve a hexa string that can be used with bitcoind's CLI interface (decoderawtransaction, sendrawtransaction)

Parameters

unsafe?

any

if true, skip all tests. if it's an object, it's expected to contain a set of flags to skip certain tests:

disableAll: disable all checks
disableLargeFees: disable checking for fees that are too large
disableIsFullySigned: disable checking if all inputs are fully signed
disableDustOutputs: disable checking if there are no outputs that are dust amounts
disableMoreOutputThanInput: disable checking if the transaction spends more bitcoins than the sum of the input amounts

Returns

string

setInputScript()

setInputScript(options, unlockScriptOrCallback): Transaction

Defined in: node_modules/@opcat-labs/opcat/types/transaction/transaction.d.cts:533

Sets the input script for a transaction input.

Parameters

options

any

Either an input index number or an options object

unlockScriptOrCallback

Either a script or callback function that returns a script

Function | Script

Returns

Transaction

Returns the transaction instance for chaining

setInputSequence()

setInputSequence(inputIndex, sequence): Transaction

Defined in: node_modules/@opcat-labs/opcat/types/transaction/transaction.d.cts:540

Sets the sequence number for a specific transaction input.

Parameters

inputIndex

number

The index of the input to update.

sequence

number

The sequence number to set.

Returns

Transaction

Returns the transaction instance for chaining.

setLockTime()

setLockTime(nLockTime): Transaction

Defined in: node_modules/@opcat-labs/opcat/types/transaction/transaction.d.cts:565

Sets the lock time for the transaction.

Parameters

nLockTime

number

The lock time to set.

Returns

Transaction

Returns the transaction instance for chaining.

setOutput()

setOutput(outputIndex, outputOrcb): Transaction

Defined in: node_modules/@opcat-labs/opcat/types/transaction/transaction.d.cts:549

Sets an output at the specified index, either directly or via a callback function. If a callback is provided, it will be invoked with the transaction instance to generate the output value. Automatically updates the change output after setting.

Parameters

outputIndex

number

The index of the output to set

outputOrcb

any

The output value or a callback function that returns the output value

Returns

Transaction

Returns the transaction instance for chaining

shuffleOutputs()

shuffleOutputs(): Transaction

Defined in: node_modules/@opcat-labs/opcat/types/transaction/transaction.d.cts:417

Randomize this transaction's outputs ordering. The shuffling algorithm is a version of the Fisher-Yates shuffle.

Returns

Transaction

this

sign()

sign(privateKey, sigtype?): Transaction

Defined in: node_modules/@opcat-labs/opcat/types/transaction/transaction.d.cts:455

Sign the transaction using one or more private keys.

It tries to sign each input, verifying that the signature will be valid (matches a public key).

Parameters

privateKey

Private key(s) to sign the transaction with.

Buffer | Buffer[]

sigtype?

number

Optional signature type.

Returns

Transaction

Returns the transaction instance for chaining.

Throws

Throws if not all UTXO information is available.

sort()

sort(): Transaction

Defined in: node_modules/@opcat-labs/opcat/types/transaction/transaction.d.cts:410

Sort a transaction's inputs and outputs according to BIP69

Returns

Transaction

this

See

sortInputs()

sortInputs(sortingFunction): Transaction

Defined in: node_modules/@opcat-labs/opcat/types/transaction/transaction.d.cts:436

Sort this transaction's inputs, according to a given sorting function that takes an array as argument and returns a new array, with the same elements but with a different order.

Parameters

sortingFunction

Function

Returns

Transaction

this

sortOutputs()

sortOutputs(sortingFunction): Transaction

Defined in: node_modules/@opcat-labs/opcat/types/transaction/transaction.d.cts:427

Sort this transaction's outputs, according to a given sorting function that takes an array as argument and returns a new array, with the same elements but with a different order. The argument function MUST NOT modify the order of the original array

Parameters

sortingFunction

Function

Returns

Transaction

this

to()

to(address, amount): Transaction

Defined in: node_modules/@opcat-labs/opcat/types/transaction/transaction.d.cts:326

Add an output to the transaction.

Beware that this resets all the signatures for inputs (in further versions, SIGHASH_SINGLE or SIGHASH_NONE signatures will not be reset).

Parameters

address

string | Address | Address[]

amount

number

in satoshis

Returns

Transaction

this, for chaining

toBuffer()

toBuffer(): Buffer

Defined in: node_modules/@opcat-labs/opcat/types/transaction/transaction.d.cts:109

Converts the transaction to a Buffer.

Returns

Buffer

The serialized transaction as a Buffer.

toBufferWriter()

toBufferWriter(forTxHash, writer?): BufferWriter

Defined in: node_modules/@opcat-labs/opcat/types/transaction/transaction.d.cts:130

Serializes the transaction to a BufferWriter.

Parameters

forTxHash

boolean

Whether to serialize for transaction hash calculation (excludes some fields)

writer?

BufferWriter

Optional BufferWriter instance to write to

Returns

BufferWriter

The BufferWriter containing serialized transaction data

toHex()

toHex(): string

Defined in: node_modules/@opcat-labs/opcat/types/transaction/transaction.d.cts:65

Returns

string

toJSON()

toJSON(): any

Defined in: node_modules/@opcat-labs/opcat/types/transaction/transaction.d.cts:153

Returns

any

toTxHashPreimage()

toTxHashPreimage(): Buffer

Defined in: node_modules/@opcat-labs/opcat/types/transaction/transaction.d.cts:123

Converts the transaction to a hash preimage by serializing it into a buffer.

Returns

Buffer

The serialized transaction data as a buffer.

uncheckedAddInput()

uncheckedAddInput(input): this

Defined in: node_modules/@opcat-labs/opcat/types/transaction/transaction.d.cts:269

Add an input to this transaction, without checking that the input has information about the output that it's spending.

Parameters

input

Input

Returns

this

Transaction this, for chaining

verify()

verify(notVerifyInput?): string | true

Defined in: node_modules/@opcat-labs/opcat/types/transaction/transaction.d.cts:516

Check that a transaction passes basic sanity tests. If not, return a string describing the error. This function contains the same logic as CheckTransaction in bitcoin core.

Checks include:

Non-empty inputs and outputs
Valid output satoshis (non-negative, not exceeding MAX_MONEY)
No duplicate inputs
Coinbase script size validation (if coinbase)
Input null checks and verification (if not coinbase and notVerifyInput is false)

Parameters

notVerifyInput?

boolean

Whether to skip input verification

Returns

string | true

Returns true if valid, or an error message string if invalid

verifyInputScript()

verifyInputScript(inputIndex): boolean

Defined in: node_modules/@opcat-labs/opcat/types/transaction/transaction.d.cts:646

Verifies the input script for a specific input index in the transaction.

Parameters

inputIndex

number

The index of the input to verify.

Returns

boolean

True if the input script is valid, false otherwise.

verifyScript()

verifyScript(inputIndex): boolean

Defined in: node_modules/@opcat-labs/opcat/types/transaction/transaction.d.cts:640

Verifies the script for a specific transaction input.

Parameters

inputIndex

number

Index of the input to verify.

Returns

boolean

True if the script verification passes.

Throws

If input at given index doesn't exist.

verifySignature()

verifySignature(sig, pubkey, nin): boolean

Defined in: node_modules/@opcat-labs/opcat/types/transaction/transaction.d.cts:500

Verifies a signature for this transaction.

Parameters

sig

Buffer

The signature to verify.

pubkey

Buffer

The public key corresponding to the signature.

nin

number

The input index being signed.

Returns

boolean

True if the signature is valid, false otherwise.

Class: Transaction

Param​

Throws​

Constructors​

new Transaction()​

Parameters​

serialized?​

Returns​

Throws​

Properties​

_changeAddress​

_changeData​

_changeIndex​

_changeScript​

_fee​

_feePerKb​

_inputAmount​

_inputsMap​

_outputAmount​

_outputsMap​

_privateKey​

_sigType​

hash​

id​

inputs​

nLockTime​

outputs​

sealed​

toObject()​

Returns​

toString()​

Returns​

uncheckedSerialize()​

Returns​

version​

Accessors​

inputAmount​

Get Signature​

Returns​

outputAmount​

Get Signature​

Returns​

Methods​

_isMissingSignatures()​

Parameters​

opts​

disableIsFullySigned?​

Returns​

addData()​

Parameters​

value​

Returns​

addDummyInput()​

Parameters​

script​

satoshis​

Returns​

addInput()​

Parameters​

input​

outputScript?​

satoshis?​

data?​

Returns​

Throws​

addInputFromPrevTx()​

Parameters​

prevTx​

outputIndex?​

Returns​

Throws​

addOutput()​

Parameters​

output​

Returns​

addSafeData()​

Parameters​

value​

Returns​

applySignature()​

Param

Throws

Constructors

new Transaction()

Parameters

serialized?

Returns

Throws

Properties

_changeAddress

_changeData

_changeIndex

_changeScript

_fee

_feePerKb

_inputAmount

_inputsMap

_outputAmount

_outputsMap

_privateKey

_sigType

hash

id

inputs

nLockTime

outputs

sealed

toObject()

Returns

toString()

Returns

uncheckedSerialize()

Returns

version

Accessors

inputAmount

Get Signature

Returns

outputAmount

Get Signature

Returns

Methods

_isMissingSignatures()

Parameters

opts

disableIsFullySigned?

Returns

addData()

Parameters

value

Returns

addDummyInput()

Parameters

script

satoshis

Returns

addInput()

Parameters

input

outputScript?

satoshis?

data?

Returns

Throws

addInputFromPrevTx()

Parameters

prevTx

outputIndex?

Returns

Throws

addOutput()

Parameters

output

Returns

addSafeData()

Parameters

value

Returns

applySignature()

Parameters