Merge pull request #12 from debris/master

simplifie contract creation && calls, improved added examples

2 files changed, 243 insertions, 5 deletions

diff --git a/lib/abi.js b/lib/abi.js
new file mode 100644
index 000000000..3df0fe684
--- /dev/null
+++ b/lib/abi.js
@@ -0,0 +1,200 @@
+/*
+    This file is part of ethereum.js.
+
+    ethereum.js is free software: you can redistribute it and/or modify
+    it under the terms of the GNU Lesser General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    ethereum.js is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU Lesser General Public License for more details.
+
+    You should have received a copy of the GNU Lesser General Public License
+    along with ethereum.js.  If not, see <http://www.gnu.org/licenses/>.
+*/
+/** @file abi.js
+ * @authors:
+ *   Marek Kotewicz <marek@ethdev.com>
+ * @date 2014
+ */
+
+var findIndex = function (array, callback) {
+    var end = false;
+    var i = 0;
+    for (; i < array.length && !end; i++) {
+        end = callback(array[i]);
+    }
+    return end ? i - 1 : -1;
+};
+
+var findMethodIndex = function (json, methodName) {
+    return findIndex(json, function (method) {
+        return method.name === methodName;
+    });
+};
+
+var padLeft = function (number, n) {
+    return (new Array(n * 2 - number.toString().length + 1)).join("0") + number;
+};
+
+var setupInputTypes = function () {
+    var prefixedType = function (prefix) {
+        return function (type, value) {
+            var expected = prefix;
+            if (type.indexOf(expected) !== 0) {
+                return false;
+            }
+
+            var padding = parseInt(type.slice(expected.length)) / 8;
+            return padLeft(value, padding);
+        };
+    };
+
+    var namedType = function (name, padding, formatter) {
+        return function (type, value) {
+            if (type !== name) {
+                return false; 
+            }
+
+            return padLeft(formatter ? value : formatter(value), padding);
+        };
+    };
+
+    var formatBool = function (value) {
+        return value ? '1' : '0';
+    };
+
+    return [
+        prefixedType('uint'),
+        prefixedType('int'),
+        namedType('address', 20),
+        namedType('bool', 1, formatBool),
+    ];
+};
+
+var inputTypes = setupInputTypes();
+
+var toAbiInput = function (json, methodName, params) {
+    var bytes = "";
+    var index = findMethodIndex(json, methodName);
+    
+    if (index === -1) {
+        return;
+    }
+
+    // it needs to be checked in WebThreeStubServer 
+    // something wrong might be with this additional zero
+    bytes = bytes + index + 'x' + '0';
+    var method = json[index];
+    
+    for (var i = 0; i < method.inputs.length; i++) {
+        var found = false;
+        for (var j = 0; j < inputTypes.length && !found; j++) {
+            var val = parseInt(params[i]).toString(16);
+            found = inputTypes[j](method.inputs[i].type, val);
+        }
+        if (!found) {
+            console.error('unsupported json type: ' + method.inputs[i].type);
+        }
+        bytes += found;
+    }
+    return bytes;
+};
+
+var setupOutputTypes = function () {
+    var prefixedType = function (prefix) {
+        return function (type) {
+            var expected = prefix;
+            if (type.indexOf(expected) !== 0) {
+                return -1;
+            }
+            
+            var padding = parseInt(type.slice(expected.length)) / 8;
+            return padding * 2;
+        };
+    };
+
+    var namedType = function (name, padding) {
+        return function (type) {
+            return name === type ? padding * 2: -1;
+        };
+    };
+
+    var formatInt = function (value) {
+        return parseInt(value, 16);
+    };
+
+    var formatBool = function (value) {
+        return value === '1' ? true : false;
+    };
+
+    return [
+    { padding: prefixedType('uint'), format: formatInt },
+    { padding: prefixedType('int'), format: formatInt },
+    { padding: namedType('address', 20) },
+    { padding: namedType('bool', 1), format: formatBool }
+    ];
+};
+
+var outputTypes = setupOutputTypes();
+
+var fromAbiOutput = function (json, methodName, output) {
+    var index = findMethodIndex(json, methodName);
+
+    if (index === -1) {
+        return;
+    }
+    
+    output = output.slice(2);
+
+    var result = [];
+    var method = json[index];
+    for (var i = 0; i < method.outputs.length; i++) {
+        var padding = -1;
+        for (var j = 0; j < outputTypes.length && padding === -1; j++) {
+            padding = outputTypes[j].padding(method.outputs[i].type);
+        }
+
+        if (padding === -1) {
+            // not found output parsing
+            continue;
+        }
+        var res = output.slice(0, padding);
+        var formatter = outputTypes[j - 1].format;
+        result.push(formatter ? formatter(res): res);
+        output = output.slice(padding);
+    }
+
+    return result;
+};
+
+var inputParser = function (json) {
+    var parser = {};
+    json.forEach(function (method) {
+        parser[method.name] = function () {
+            var params = Array.prototype.slice.call(arguments);
+            return toAbiInput(json, method.name, params);
+        };
+    });
+
+    return parser;
+};
+
+var outputParser = function (json) {
+    var parser = {};
+    json.forEach(function (method) {
+        parser[method.name] = function (output) {
+            return fromAbiOutput(json, method.name, output);
+        };
+    });
+
+    return parser;
+};
+
+module.exports = {
+    inputParser: inputParser,
+    outputParser: outputParser
+};
+
diff --git a/lib/main.js b/lib/main.js
index c3ed22f8b..7990691de 100644
--- a/lib/main.js
+++ b/lib/main.js
@@ -22,6 +22,8 @@
  * @date 2014
  */
 
+var abi = require('./abi');
+
 function flattenPromise (obj) {
     if (obj instanceof Promise) {
         return Promise.resolve(obj);
@@ -77,6 +79,7 @@ var ethMethods = function () {
     var methods = [
     { name: 'balanceAt', call: 'eth_balanceAt' },
     { name: 'stateAt', call: 'eth_stateAt' },
+    { name: 'storageAt', call: 'eth_storageAt' },
     { name: 'countAt', call: 'eth_countAt'},
     { name: 'codeAt', call: 'eth_codeAt' },
     { name: 'transact', call: 'eth_transact' },
@@ -84,8 +87,9 @@ var ethMethods = function () {
     { name: 'block', call: blockCall },
     { name: 'transaction', call: transactionCall },
     { name: 'uncle', call: uncleCall },
-    { name: 'compile', call: 'eth_compile' },
-    { name: 'lll', call: 'eth_lll' }
+    { name: 'compilers', call: 'eth_compilers' },
+    { name: 'lll', call: 'eth_lll' },
+    { name: 'solidity', call: 'eth_solidity' }
     ];
     return methods;
 };
@@ -290,9 +294,8 @@ var web3 = {
     }
 };
 
-var eth = web3.eth;
-setupMethods(eth, ethMethods());
-setupProperties(eth, ethProperties());
+setupMethods(web3.eth, ethMethods());
+setupProperties(web3.eth, ethProperties());
 setupMethods(web3.db, dbMethods());
 setupMethods(web3.shh, shhMethods());
 
@@ -452,5 +455,40 @@ function messageHandler(data) {
     }
 }
 
+web3.contract = function (address, desc) {
+    var inputParser = abi.inputParser(desc);
+    var outputParser = abi.outputParser(desc);
+
+    var contract = {};
+
+    desc.forEach(function (method) {
+        contract[method.name] = function () {
+            var params = Array.prototype.slice.call(arguments);
+            var parsed = inputParser[method.name].apply(null, params);
+
+            var onSuccess = function (result) {
+                return outputParser[method.name](result);
+            };
+
+            return {
+                call: function (extra) {
+                    extra = extra || {};
+                    extra.to = address;
+                    extra.data = parsed;
+                    return web3.eth.call(extra).then(onSuccess);
+                },
+                transact: function (extra) {
+                    extra = extra || {};
+                    extra.to = address;
+                    extra.data = parsed;
+                    return web3.eth.transact(extra).then(onSuccess);
+                }
+            };
+        };
+    });
+         
+    return contract;
+};
+
 module.exports = web3;