flocore-node/lib/services/transaction.js
2017-01-19 16:11:04 -05:00

109 lines
2.5 KiB
JavaScript

'use strict';
var BaseService = require('../service');
var inherits = require('util').inherits;
var bitcore = require('bitcore-lib');
function TransactionService(options) {
BaseService.call(this, options);
this.currentTransactions = {};
}
inherits(TransactionService, BaseService);
TransactionService.dependencies = [
'db'
];
TransactionService.prototype.start = function(callback) {
var self = this;
this.store = this.node.services.db.store;
this.node.services.db.getPrefix(this.name, function(err, prefix) {
if(err) {
return callback(err);
}
self.prefix = prefix;
callback();
});
};
TransactionService.prototype.stop = function(callback) {
setImmediate(callback);
};
TransactionService.prototype.blockHandler = function(block, connectBlock, callback) {
var action = 'put';
if (!connectBlock) {
action = 'del';
}
var operations = [];
this.currentTransactions = {};
for(var i = 0; i < block.transactions.length; i++) {
var tx = block.transactions[i];
tx.__height = block.__height;
this.currentTransactions[tx.id] = tx;
operations.push({
type: action,
key: this._encodeTransactionKey(tx.id),
value: this._encodeTransactionValue(tx)
});
}
setImmediate(function() {
callback(null, operations);
});
};
TransactionService.prototype.getTransaction = function(txid, callback) {
var self = this;
if(self.currentTransactions[txid]) {
return setImmediate(function() {
callback(null, self.currentTransactions[txid]);
});
}
var key = self._encodeTransactionKey(txid);
self.node.services.db.store.get(key, function(err, buffer) {
if(err) {
return callback(err);
}
var tx = self._decodeTransactionValue(buffer);
callback(null, tx);
});
};
TransactionService.prototype._encodeTransactionKey = function(txid) {
return Buffer.concat([this.prefix, new Buffer(txid, 'hex')]);
};
TransactionService.prototype._decodeTransactionKey = function(buffer) {
return buffer.slice(2).toString('hex');
};
TransactionService.prototype._encodeTransactionValue = function(transaction, height) {
var heightBuffer = new Buffer(4);
heightBuffer.writeUInt32BE();
return new Buffer.concat([heightBuffer, transaction.toBuffer()]);
};
TransactionService.prototype._decodeTransactionValue = function(buffer) {
var height = buffer.readUInt32BE();
var transaction = new bitcore.Transaction(buffer.slice(4));
transaction.__height = height;
return transaction;
};
module.exports = TransactionService;