Transactions

Namespace: nem.model.transactions

Public methods:

• prepare
• send
• prepareMessage

Keywords:

• transferTransaction
• mosaicTransferTransaction
• signatureTransaction

This namespace is used to prepare and send transactions.

For now only preparation of simple and mosaics transactions with encrypted, unencrypted and hex messages are implemented.

3.1 - Create and prepare transaction objects

In part 2 you can see in the examples how to build a transfer transaction object, with or without data.

Transaction objects you will create via nem.model.objects are un-prepared transaction objects. They only contain raw / incomplete data and need to be arranged before being signed and sent.

Using the prepare method takes different parameters depending of the transaction object.

Parameters

transferTransaction

mosaicTransferTransaction

Usage:

// Prepare a transaction object
var preparedTransaction = nem.model.transactions.prepare("keyword")(param1, param2, ...);

Transfer transaction example:

// Create an object with parameters
var transferTransaction = nem.model.objects.create("transferTransaction")("TBCI2A67UQZAKCR6NS4JWAEICEIGEIM72G3MVW5S", 10, "Hello");

// Prepare the above object
var transactionEntity = nem.model.transactions.prepare("transferTransaction")(common, transferTransaction, nem.model.network.data.testnet.id)

Return:

{
	type: 257,
  	version: -1744830463,
  	signer: '0257b05f601ff829fdff84956fb5e3c65470a62375a1cc285779edd5ca3b42f6',
  	timeStamp: 62995509,
  	deadline: 62999109,
  	recipient: 'TBCI2A67UQZAKCR6NS4JWAEICEIGEIM72G3MVW5S',
  	amount: 10000000,
  	fee: 2000000,
  	message: { type: 1, payload: '48656c6c6f' },
  	mosaics: null
}

You can easily see the difference between an un-prepared transaction object (2.2) and above prepared object.

Note:

Amounts are in the smallest unit possible in a prepared transaction object:

1000000 = 1 XEM

Signature transaction example:

// Create an object with parameters (multisig account address and inner transaction hash)
var signatureTransaction = nem.model.objects.create("signatureTransaction")("TBCI2A67UQZAKCR6NS4JWAEICEIGEIM72G3MVW5S", "161d7f74ab9d332acd46f96650e74371d65b6e1a0f47b076bdd7ccea37903175");

// Prepare the above object
var transactionEntity = nem.model.transactions.prepare("signatureTransaction")(common, signatureTransaction, nem.model.network.data.testnet.id)

Return:

{
  type: 4098,
  version: -1744830463,
  signer: '0257b05f601ff829fdff84956fb5e3c65470a62375a1cc285779edd5ca3b42f6',
  timeStamp: 62995509,
  deadline: 62999109,
  otherHash: {
    data: '161d7f74ab9d332acd46f96650e74371d65b6e1a0f47b076bdd7ccea37903175'
  },
  otherAccount: 'TBCI2A67UQZAKCR6NS4JWAEICEIGEIM72G3MVW5S',
  fee: 6000000
}

3.2 - Sending prepared transactions

Once your transaction is prepared simply use the send method of the namespace.

Parameters

Example

// Serialize transfer transaction and announce
nem.model.transactions.send(common, transactionEntity, endpoint).then(function(res) {....});

return

A NemAnnounceResult object (http://bob.nem.ninja/docs/#nemAnnounceResult)

3.3 - Transfer transactions without mosaics

The two provided example speaks for themselves:

• See examples/node/transfer.js for node
• See examples/browser/transfer for browser

The node version contains only the strict necessary while browser example needs to handle form and update fees.

3.4 - Transfer transactions with mosaics

• See examples/node/mosaicTransfer.js for node
• See examples/browser/mosaicTransfer for browser

Similar to transfer transaction, it use the same un-prepared transferTransaction object, but needs an array of mosaicAttachment objects.

Keyword of the preparation function is mosaicTransferTransaction.

Preparation of mosaic transfer transactions requires a mosaicDefinitionMetaDataPair object containing mosaic definitions of the mosaics you are joining to the transaction.

Definitions are needed to know informations about the included mosaic(s) and calculate quantity and fee accordingly.

Two ways are possible to get mosaic definitions:

1) You can take it from NIS API using http://bob.nem.ninja/docs/#retrieving-mosaic-definitions and put the definition into model/objects.js, in the mosaicDefinitionMetaDataPair object (like shown by the comments). If mosaics used in your application are fixed, it is the way to go.

2) Query the network using the embedded API requests (nem.com.requests.namespace.mosaicDefinitions) as shown in the examples. If mosaics used in your application are not fixed, it is the way to go.