aboutsummaryrefslogtreecommitdiffstats
path: root/cmd/mist/assets/ext/ethereum.js/lib/contract.js
blob: e71734d0b4ecccfa49b311d83033749126492f97 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
/*
    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 contract.js
 * @authors:
 *   Marek Kotewicz <marek@ethdev.com>
 * @date 2014
 */

var web3 = require('./web3'); // jshint ignore:line
var abi = require('./abi');

/**
 * This method should be called when we want to call / transact some solidity method from javascript
 * it returns an object which has same methods available as solidity contract description
 * usage example: 
 *
 * var abi = [{
 *      name: 'myMethod',
 *      inputs: [{ name: 'a', type: 'string' }],
 *      outputs: [{name: 'd', type: 'string' }]
 * }];  // contract abi
 *
 * var myContract = web3.eth.contract('0x0123123121', abi); // creation of contract object
 *
 * myContract.myMethod('this is test string param for call'); // myMethod call (implicit, default)
 * myContract.call().myMethod('this is test string param for call'); // myMethod call (explicit)
 * myContract.transact().myMethod('this is test string param for transact'); // myMethod transact
 *
 * @param address - address of the contract, which should be called
 * @param desc - abi json description of the contract, which is being created
 * @returns contract object
 */

var contract = function (address, desc) {

    desc.forEach(function (method) {
        // workaround for invalid assumption that method.name is the full anonymous prototype of the method.
        // it's not. it's just the name. the rest of the code assumes it's actually the anonymous
        // prototype, so we make it so as a workaround.
        if (method.name.indexOf('(') === -1) {
            var displayName = method.name;
            var typeName = method.inputs.map(function(i){return i.type; }).join();
            method.name = displayName + '(' + typeName + ')';
        }
    });

    var inputParser = abi.inputParser(desc);
    var outputParser = abi.outputParser(desc);

    var result = {};

    result.call = function (options) {
        result._isTransact = false;
        result._options = options;
        return result;
    };

    result.transact = function (options) {
        result._isTransact = true;
        result._options = options;
        return result;
    };

    result._options = {};
    ['gas', 'gasPrice', 'value', 'from'].forEach(function(p) {
        result[p] = function (v) {
            result._options[p] = v;
            return result;
        };
    });


    desc.forEach(function (method) {

        var displayName = abi.methodDisplayName(method.name);
        var typeName = abi.methodTypeName(method.name);

        var impl = function () {
            var params = Array.prototype.slice.call(arguments);
            var signature = abi.methodSignature(method.name);
            var parsed = inputParser[displayName][typeName].apply(null, params);

            var options = result._options || {};
            options.to = address;
            options.data = signature + parsed;
            
            var isTransact = result._isTransact === true || (result._isTransact !== false && !method.constant);
            var collapse = options.collapse !== false;
            
            // reset
            result._options = {};
            result._isTransact = null;

            if (isTransact) {
                // it's used byt natspec.js
                // TODO: figure out better way to solve this
                web3._currentContractAbi = desc;
                web3._currentContractAddress = address;
                web3._currentContractMethodName = method.name;
                web3._currentContractMethodParams = params;

                // transactions do not have any output, cause we do not know, when they will be processed
                web3.eth.transact(options);
                return;
            }
            
            var output = web3.eth.call(options);
            var ret = outputParser[displayName][typeName](output);
            if (collapse)
            {
                if (ret.length === 1)
                    ret = ret[0];
                else if (ret.length === 0)
                    ret = null;
            }
            return ret;
        };

        if (result[displayName] === undefined) {
            result[displayName] = impl;
        }

        result[displayName][typeName] = impl;

    });

    return result;
};

module.exports = contract;