Merge branch 'develop'

Incorporate the progress on the TransactionBuilder into the master branch
for greater visibility. While the library is functional as an Open Assets
explorer, the TransactionBuilder does not yet have all of the features of
the reference implementation. In the event others find this library useful,
I'd like them to be aware of the progress made to-date.

README.md

@@ -7,12 +7,12 @@ About the Open Assets Protocol
 ------------------------------
 The Open Assets Protocol is a simple and powerful protocol built on top of the Bitcoin Blockchain. It allows issuance and transfer of user-created assets. The Open Assets Protocol is an evolution of the concept of colored coins.
 
-The protocol specification is publicly maintained at the official [OpenAssets repository](https://github.com/OpenAssets/open-assets-protocol). The [reference implementation](https://github.com/OpenAssets/openassets) exists as a Python module. This project provides a translation to JavaScript, packaged as an NPM module.
+The protocol specification is publicly maintained at the official [OpenAssets repository](https://github.com/OpenAssets/open-assets-protocol). The [reference implementation](https://github.com/OpenAssets/openassets) exists as a Python module. This project provides a translation to JavaScript, packaged as an `npm` module.
 
 Installation
 ------------
 
-OpenAssets is provided as a [NPM](http://npmjs.org/) module for easy installation:
+OpenAssets is provided as an [npm](https://www.npmjs.org/package/openassets) module for easy installation:
 
 ```npm install openassets```
 

lib/protocol/SpendableOutput.js

@@ -0,0 +1,36 @@
+/* Copyright (c) 2014, Andrew Hart <[email protected]>
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+'use strict';
+
+/**
+ * SpendableOutput
+ *
+ * Represents a transaction output with information about the asset quantity
+ * and asset id associated with it
+**/
+
+/**
+ * Constructor
+ * @param TransactionOut    outPoint  An object that can be used to locate the output
+ * @param TransactionOutput output    The actual output object
+**/
+var SpendableOutput = function (outPoint, output) {
+  this.outPoint = outPoint;
+  this.output   = output;
+};
+
+// The public API for this object
+module.exports = SpendableOutput;

lib/protocol/TransactionBuilder.js

@@ -0,0 +1,166 @@
+/* Copyright (c) 2014, Andrew Hart <[email protected]>
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+'use strict';
+
+var bitcore  = require('bitcore'),
+    MarkerOutput = require('./MarkerOutput');
+
+/**
+ * TransactionBuilder
+ *
+ * Provides methods for constructing Open Assets transactions
+**/
+
+/**
+ * Constructor
+ * @param int  dustAmount  The minimum allowed output data
+**/
+var TransactionBuilder = function (dustAmount) {
+  self.dustAmount = dustAmount;
+};
+
+/**
+ * Create a transaction for issuing an asset
+ * @param TransferParameters issuanceSpec  The parameters of the issuance
+ * @param Buffer             metadata      The metadata to be embedded in the transaction
+ * @param int                fees          The fees to include in the transaction
+ * @return  Transaction      an unsigned transaction for issuing an asset
+**/
+TransactionBuilder.prototype.issue = function (issuanceSpec, metadata, fees) {
+  var inputs, totalAmount, outputInfo, builder, tx;
+
+  // Returns an object containing two keys: inputs, totalAmount
+  outputInfo = _collectUncoloredOutputs(
+    issuanceSpec.unspentOutputs, 2 * self.dustAmount + fees);
+
+  builder = (new bitcore.TransactionBuilder({
+    feeSat: fees,
+    amountSat: outputInfo.totalAmount
+  }))
+    .setUnspent('foo')
+    .setOutputs('foo');
+
+
+
+};
+
+TransactionBuilder.prototype.transfer = function (transferSpec, fees) {
+
+};
+
+TransactionBuilder.prototype.transferBitcoin = function (transferSpec, fees) {
+
+};
+
+TransactionBuilder.prototype.transferAssets = function (assetId, transferSpec, btcChangeScript, fees) {
+
+};
+
+TransactionBuilder.prototype.bitcoinAssetSwap = function (btcTransferSpec, assetId, assetTransferSpec, fees) {
+
+};
+
+TransactionBuilder.prototype.assetAssetSwap = function (asset1Id, asset1TransferSpec, asset2Id, asset2TransferSpec, fees) {
+
+};
+
+/**
+ * Return a list of uncolored outputs for the specified amount
+ * @param  array(SpendableOutput) unspentOutputs  The list of available outputs
+ * @param  int                    amount          The amount to collect
+ * @return Object(outputs:array(SpendableOutput),totalAmount:int)
+**/
+TransactionBuilder.prototype._collectUncoloredOutputs = function(unspentOutputs, amount) {
+  var totalAmount = 0, result = [];
+
+  unspentOutputs.forEach(function (spendableOutput) {
+    if (spendableOutput.output.assetId == null) {
+      result.push(spendableOutput);
+      totalAmount += spendableOutput.output.value);
+    }
+
+    if (totalAmount >= amount) {
+      return {
+        outputs: result,
+        totalAmount: totalAmount
+      };
+    }
+
+    throw new Error("Insufficient funds");
+  });
+};
+
+/**
+ * Create an uncolored output
+ * @param Buffer   script  The output script
+ * @param int      value   The satoshi value of the output
+ * @return Object  An object representing the uncolored output
+**/
+TransactionBuilder.prototype._getUncoloredOutput = function (script, value) {
+  if (value < this.dustAmount) {
+    throw Error('The value of the output would be too small, and the output would be considered "dust"');
+  }
+
+  return {v: value, s: script};
+};
+
+/**
+ * Return a list of colored outputs for the specified quantity
+ * @param array(SpendableOutput)  unspentOutputs  The list of available outputs
+ * @param Buffer                  assetId         The ID of the asset to collect
+ * @param int                     quantity        The asset quantity to collect
+ * @return Object(outputs:array(SpendableOutput),quantity:int)
+**/
+TransactionBuilder.prototype._collectColoredOutputs = function (unspentOutputs, assetId, assetQuantity) {
+  var totalQuantity = 0,
+      result = [];
+
+  unspentOutputs.forEach(function (spendableOutput) {
+    if (spendableOutput.output.assetId == assetId) {
+      result.push(spendableOutput);
+      totalQuantity += spendableOutput.output.assetQuantity;
+    }
+
+    if (totalQuantity >= assetQuantity) {
+      return {outputs: result, quantity: totalQuantity};
+    }
+  });
+
+  throw new Error("An insufficient amount of assets is available");
+};
+
+/**
+ * Create a colored output
+ * @param Buffer   script  The output script
+ * @return Object  An object representing the colored output
+**/
+TransactionBuilder.prototype._getColoredOutput = function (script) {
+  return {v: this.dustAmount, s: script};
+};
+
+/** 
+ * Create a marker output
+ *
+ * @param array(int)  assetQuantities  The asset quantity list
+ * @param Buffer      metadata         The metadata contained in the output
+ * @return Object     An object representing the marker output
+**/
+TransactionBuilder.prototype._getMarkerOutput = function (assetQuantities, metadata) {
+  var output  = new MarkerOutput(assetQuantities, metadata),
+      payload = mo.serializePayload(),
+      script  = mo.buildScript(payload);
+  return {v: 0, s: script}; // Marker output has value 0 satoshis
+};

lib/protocol/TransferParameters.js

@@ -0,0 +1,39 @@
+/* Copyright (c) 2014, Andrew Hart <[email protected]>
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+'use strict';
+
+/**
+ * TransferParameters
+ *
+ * Encapsulates the details of a Bitcoin or asset transfer
+**/
+
+/**
+ * Constructor
+ * @param array(SpendableOutput) unspentOutputs  The unspent outputs available for the transaction
+ * @param Buffer                 toScript        The output script to which to send Bitcoin/assets
+ * @param Buffer                 changeScript    The output script to which to send remaining change
+ * @param int                    amount          The asset quantity or number of satoshis sent in the tx
+**/
+var TransferParameters = function (unspentOutputs, toScript, changeScript, amount) {
+  self.unspentOutputs = unspentOutputs;
+  self.toScript       = toScript;
+  self.changeScript   = changeScript;
+  self.amount         = amount;
+};
+
+// The public API for this object
+module.exports = TransferParameters;