@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.