@iota/transaction

Utilities and validators for transactions.

Installation

Install using npm:

npm install @iota/transaction

or using yarn:

yarn add @iota/transaction

API Reference

• transaction

  • static

    • .transactionHash(buffer, [offset])

    • .isTransaction(transaction, [minWeightMagnitude])

    • .isTailTransaction(transaction)

    • .isHeadTransaction(transaction)

  • inner

    • ~isMultipleOfTransactionLength(lengthOrOffset)

    • ~signatureOrMessage(buffer)

    • ~address(buffer, [offset])

    • ~value(buffer, [offset])

    • ~obsoleteTag(buffer, [offset])

    • ~issuanceTimestamp(buffer, [offset])

    • ~currentIndex(buffer, [offset])

    • ~lastIndex(buffer, [offset])

    • ~bundle(buffer, [offset])

    • ~trunkTransaction(buffer, [offset])

    • ~branchTransaction(buffer, [offset])

    • ~tag(buffer, [offset])

    • ~attachmentTimestamp(buffer, [offset])

    • ~attachmentTimestampLowerBound(buffer, [offset])

    • ~attachmentTimestampUpperBound(buffer, [offset])

    • ~transactionNonce(buffer, [offset])

    • ~bundle(buffer, [offset])

transaction.transactionHash(buffer, [offset])

Summary: Generates the transaction hash for a given transaction.
Throws:

• errors.ILLEGAL_TRANSACTION_BUFFER_LENGTH : Make sure that the buffer argument contains 8,019 trits (the length of a transaction without the transaction hash).
• errors.ILLEGAL_TRANSACTION_OFFSET : Make sure that the offset argument is a multiple of 8,019 (the length of a transaction without the transaction hash).

Param	Type	Default	Description
buffer	Int8Array		Transactions in trits
[offset]	Number	0	Offset in trits to define a transaction to hash in the buffer argument

This method takes transaction trits, and returns the transaction hash.

Related methods

To validate the length of transaction trits, use the isMultipleOfTransactionLength() method.

To get a transaction's trits from the Tangle, use the getTrytes() method, then convert them to trits, using the trytesToTrits() method.

Returns: Int8Array - Transaction hash
Example

let hash = Transaction.transactionHash(transactions);

transaction.isTransaction(transaction, [minWeightMagnitude])

Summary: Validates the structure and contents of a given transaction.
Throws:

• errors.ILLEGAL_MIN_WEIGHT_MAGNITUDE : Make sure that the minWeightMagnitude argument is a number between 1 and 81.
• errors.ILLEGAL_TRANSACTION_BUFFER_LENGTH : Make sure that the transaction argument contains 8,019 trits (the length of a transaction without the transaction hash).

Param	Type	Default	Description
transaction	Int8Array		Transaction trits
[minWeightMagnitude]	number	0	Minimum weight magnitude

This method takes an array of transaction trits and validates whether they form a valid transaction by checking the following:

• Addresses in value transactions have a 0 trit at the end, which means they were generated using the Kerl hashing function
• The transaction would result in a valid hash, according to the given minWeightMagnitude argument

Related methods

To get a transaction's trits from the Tangle, use the getTrytes() method, then convert them to trits, using the trytesToTrits() method.

Returns: boolean - valid - Whether the transaction is valid.
Example

let valid = Transaction.isTransaction(transaction);

transaction.isTailTransaction(transaction)

Summary: Checks if the given transaction is a tail transaction in a bundle.
Throws:

• errors.ILLEGAL_TRANSACTION_BUFFER_LENGTH : Make sure that the transaction argument contains 8,019 trits (the length of a transaction without the transaction hash).

Param	Type	Description
transaction	Int8Array	Transaction trits

This method takes an array of transaction trits, and checks its currentIndex field to validate whether it is the tail transaction in a bundle.

Related methods

To get a transaction's trits from the Tangle, use the getTrytes() method, then convert them to trits, using the trytesToTrits() method.

Returns: boolean - tail - Whether the transaction is a tail transaction.
Example

let tail = Transaction.isTailTransaction(transaction);

transaction.isHeadTransaction(transaction)

Summary: Checks if the given transaction is a head transaction in a bundle.
Throws:

• errors.ILLEGAL_TRANSACTION_BUFFER_LENGTH : Make sure that the transaction argument contains 8,019 trits (the length of a transaction without the transaction hash).

Param	Type	Description
transaction	Int8Array	Transaction trits

This method takes an array of transaction trits, and checks its currentIndex field to validate whether it is the head transaction in a bundle.

Related methods

To get a transaction's trits from the Tangle, use the getTrytes() method, then convert them to trits, using the trytesToTrits() method.

Returns: boolean - head - Whether the transaction is a head transaction.
Example

let head = Transaction.isHeadTransaction(transaction);

transaction~isMultipleOfTransactionLength(lengthOrOffset)

Param	Type
lengthOrOffset	Int8Array

Checks if given value is a valid transaction buffer length or offset.

transaction~signatureOrMessage(buffer)

Param	Type	Description
buffer	Int8Array	Transaction trytes

Gets the signatureOrMessage field of all transactions in a bundle.

transaction~address(buffer, [offset])

Param	Type	Default	Description
buffer	Int8Array		Transaction buffer. Buffer length must be a multiple of transaction length
[offset]	Number	0	Transaction trit offset. It must be a multiple of transaction length.

Returns a copy of address field.

transaction~value(buffer, [offset])

Param	Type	Default	Description
buffer	Int8Array		Transaction buffer. Buffer length must be a multiple of transaction length.
[offset]	Number	0	Transaction trit offset. It must be a multiple of transaction length.

Returns a copy of value field.

transaction~obsoleteTag(buffer, [offset])

Param	Type	Default	Description
buffer	Int8Array		Transaction buffer. Buffer length must be a multiple of transaction length.
[offset]	Number	0	Transaction trit offset. It must be a multiple of transaction length.

Returns a copy of obsoleteTag field.

transaction~issuanceTimestamp(buffer, [offset])

Param	Type	Default	Description
buffer	Int8Array		Transaction buffer. Buffer length must be a multiple of transaction length.
[offset]	Number	0	Transaction trit offset. It must be a multiple of transaction length.

Returns a copy of issuanceTimestamp field.

transaction~currentIndex(buffer, [offset])

Param	Type	Default	Description
buffer	Int8Array		Transaction buffer. Buffer length must be a multiple of transaction length.
[offset]	Number	0	Transaction trit offset. It must be a multiple of transaction length.

Returns a copy of currentIndex field.

transaction~lastIndex(buffer, [offset])

Param	Type	Default	Description
buffer	Int8Array		Transaction buffer. Buffer length must be a multiple of transaction length.
[offset]	Number	0	Transaction trit offset. It must be a multiple of transaction length.

Returns a copy of lastIndex field.

transaction~bundle(buffer, [offset])

Param	Type	Default	Description
buffer	Int8Array		Transaction buffer. Buffer length must be a multiple of transaction length.
[offset]	Number	0	Transaction trit offset. It must be a multiple of transaction length.

Returns a copy of bundle field.

transaction~trunkTransaction(buffer, [offset])

Param	Type	Default	Description
buffer	Int8Array		Transaction buffer. Buffer length must be a multiple of transaction length.
[offset]	Number	0	Transaction trit offset. It must be a multiple of transaction length.

Returns a copy of trunkTransaction field.

transaction~branchTransaction(buffer, [offset])

Param	Type	Default	Description
buffer	Int8Array		Transaction buffer. Buffer length must be a multiple of transaction length.
[offset]	Number	0	Transaction trit offset. It must be a multiple of transaction length.

Returns a copy of branchTransaction field.

transaction~tag(buffer, [offset])

Param	Type	Default	Description
buffer	Int8Array		Transaction buffer. Buffer length must be a multiple of transaction length.
[offset]	Number	0	Transaction trit offset. It must be a multiple of transaction length.

Returns a copy of tag field.

transaction~attachmentTimestamp(buffer, [offset])

Param	Type	Default	Description
buffer	Int8Array		Transaction buffer. Buffer length must be a multiple of transaction length.
[offset]	Number	0	Transaction trit offset. It must be a multiple of transaction length.

Returns a copy of attachmentTimestamp field.

transaction~attachmentTimestampLowerBound(buffer, [offset])

Param	Type	Default	Description
buffer	Int8Array		Transaction buffer. Buffer length must be a multiple of transaction length.
[offset]	Number	0	Transaction trit offset. It must be a multiple of transaction length.

Returns a copy of attachmentTimestampLowerBound field.

transaction~attachmentTimestampUpperBound(buffer, [offset])

Param	Type	Default	Description
buffer	Int8Array		Transaction buffer. Buffer length must be a multiple of transaction length.
[offset]	Number	0	Transaction trit offset. It must be a multiple of transaction length.

Returns a copy of attachmentTimestampUpperBound field.

transaction~transactionNonce(buffer, [offset])

Param	Type	Default	Description
buffer	Int8Array		Transaction buffer. Buffer length must be a multiple of transaction length.
[offset]	Number	0	Transaction trit offset. It must be a multiple of transaction length.

Returns a copy of tansactionNonce field.

transaction~bundle(buffer, [offset])

Param	Type	Default	Description
buffer	Int8Array		Transaction buffer. Buffer length must be a multiple of transaction length.
[offset]	Number	0	Transaction trit offset. It must be a multiple of transaction length.

Returns a copy of transaction essence fields.