flocore-node/lib/services/utxo/index.js
Chris Kleeschulte 780175ee4e wip
2017-05-25 08:54:27 -04:00

153 lines
3.4 KiB
JavaScript

'use strict';
var BaseService = require('../../service');
var inherits = require('util').inherits;
var Encoding = require('./encoding');
var LRU = require('lru-cache');
function UtxoService(options) {
BaseService.call(this, options);
this._createCache({ max: 500000, dispose: this._getUtxoOperations.bind(this) });
}
inherits(UtxoService, BaseService);
UtxoService.dependencies = ['db'];
UtxoService.prototype.start = function(callback) {
var self = this;
self.db = this.node.services.db;
self.db.getPrefix(self.name, function(err, prefix) {
if (err) {
return callback(err);
}
self.prefix = prefix;
self.encoding = new Encoding(self.prefix);
callback();
});
};
UtxoService.prototype.stop = function(callback) {
if (callback) {
setImmediate(callback);
}
};
UtxoService.prototype._processInputs = function(inputs, block, connect) {
var ret = [];
for(var i = 0; i < inputs.length; i++) {
var input = inputs[i];
var key = input.prevHash + input.outputIndex;
if (input.prevTxId === tx.hash) {
ret.push(i);
continue;
}
if (connect) {
self._removeSpentOutput(key);
} else {
self._readdUnspentOutput(key);
}
}
return ret;
};
UtxoService.prototype._processOutputs = function(outputs, exclusions, block, connect) {
for(var i = 0; i < outputs.length; i++) {
var output = outputs[i];
var key = tx.hash + i;
if (exclusions.indexOf(i) > -1) {
continue;
}
self._setCache(key, block, output);
}
};
UtxoService.prototype._setCache = function(key, block, output) {
self._cache.set(key, {
output: output,
height: block.__height,
hash: block.hash,
}); // key = 36 bytes, value = (8 + 25ish) + 36 = 69 bytes
};
UtxoService.prototype._removeSpentOutput = function(key) {
var output = self._cache.peek(key);
// we don't want nuke out our
if (!output) {
return { action: 'del', key: key };
}
};
UtxoService.prototype._readdSpentOutput = function(key) {
var output = self._cache.get(key);
if (!output) {
}
};
/*
connect:
1. for all txs, for each input in the tx, remove the output that this input is spending
*/
UtxoService.prototype.blockHandler = function(block, connect) {
var self = this;
var operations = [];
for(var i = 0; i < block.transactions.length; i++) {
var tx = block.transactions[i];
var inputs = tx.inputs;
var outputs = tx.outputs;
var inputOperations = {};
if (!tx.isCoinbase()) {
inputOperations = self._processInputs(inputs, block, connect);
}
var outputRes = self._processOutputs(outputs, inputRes.exclusions || [], block, connect);
operations = operations.concat(inputRes.operations || []).concat(outputRes.operations);
}
return operations;
};
UtxoService.prototype._getUtxoOperations = function(key, value) {
this._operations.push({
action: 'put',
key: this._getOperationsKey(key, value),
value: this._getOperationsValue(value)
});
};
UtxoService.prototype._getOperationsKey = function(key, value) {
var address = utils.getAddressFromScript(value.output.script);
return self.encoding.encodeUtxoIndexKey(address, key.slice(0, 32), parseInt(key.slice(32)));
};
UtxoService.prototype._getOperationsValue = function(value) {
return self.encoding.encodeUtxoIndexValue(value.height, value.output.satoshis, value.output.script);
};
module.exports = UtxoService;