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
|
/*
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 providermanager.js
* @authors:
* Jeffrey Wilcke <jeff@ethdev.com>
* Marek Kotewicz <marek@ethdev.com>
* Marian Oancea <marian@ethdev.com>
* Gav Wood <g@ethdev.com>
* @date 2014
*/
var web3 = require('./web3'); // jshint ignore:line
/**
* Provider manager object prototype
* It's responsible for passing messages to providers
* If no provider is set it's responsible for queuing requests
* It's also responsible for polling the ethereum node for incoming messages
* Default poll timeout is 12 seconds
* If we are running ethereum.js inside ethereum browser, there are backend based tools responsible for polling,
* and provider manager polling mechanism is not used
*/
var ProviderManager = function() {
this.polls = [];
this.provider = undefined;
this.id = 1;
var self = this;
var poll = function () {
if (self.provider) {
self.polls.forEach(function (data) {
data.data._id = self.id;
self.id++;
var result = self.provider.send(data.data);
result = JSON.parse(result);
// dont call the callback if result is not an array, or empty one
if (result.error || !(result.result instanceof Array) || result.result.length === 0) {
return;
}
data.callback(result.result);
});
}
setTimeout(poll, 1000);
};
poll();
};
/// sends outgoing requests
ProviderManager.prototype.send = function(data) {
data.args = data.args || [];
data._id = this.id++;
if (this.provider === undefined) {
console.error('provider is not set');
return null;
}
//TODO: handle error here?
var result = this.provider.send(data);
result = JSON.parse(result);
if (result.error) {
console.log(result.error);
return null;
}
return result.result;
};
/// setups provider, which will be used for sending messages
ProviderManager.prototype.set = function(provider) {
this.provider = provider;
};
/// this method is only used, when we do not have native qt bindings and have to do polling on our own
/// should be callled, on start watching for eth/shh changes
ProviderManager.prototype.startPolling = function (data, pollId, callback) {
this.polls.push({data: data, id: pollId, callback: callback});
};
/// should be called to stop polling for certain watch changes
ProviderManager.prototype.stopPolling = function (pollId) {
for (var i = this.polls.length; i--;) {
var poll = this.polls[i];
if (poll.id === pollId) {
this.polls.splice(i, 1);
}
}
};
module.exports = ProviderManager;
|
