103 lines
		
	
	
		
			3.1 KiB
		
	
	
	
		
			JavaScript
		
	
	
	
	
	
			
		
		
	
	
			103 lines
		
	
	
		
			3.1 KiB
		
	
	
	
		
			JavaScript
		
	
	
	
	
	
/*
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    This file is part of ethereum.js.
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    ethereum.js is free software: you can redistribute it and/or modify
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    it under the terms of the GNU Lesser General Public License as published by
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    the Free Software Foundation, either version 3 of the License, or
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    (at your option) any later version.
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    ethereum.js is distributed in the hope that it will be useful,
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    but WITHOUT ANY WARRANTY; without even the implied warranty of
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    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
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    GNU Lesser General Public License for more details.
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    You should have received a copy of the GNU Lesser General Public License
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    along with ethereum.js.  If not, see <http://www.gnu.org/licenses/>.
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*/
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/** @file providermanager.js
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 * @authors:
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 *   Jeffrey Wilcke <jeff@ethdev.com>
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 *   Marek Kotewicz <marek@ethdev.com>
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 *   Marian Oancea <marian@ethdev.com>
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 *   Gav Wood <g@ethdev.com>
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 * @date 2014
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 */
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var web3 = require('./web3'); 
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var jsonrpc = require('./jsonrpc');
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/**
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 * Provider manager object prototype
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 * It's responsible for passing messages to providers
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 * If no provider is set it's responsible for queuing requests
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 * It's also responsible for polling the ethereum node for incoming messages
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 * Default poll timeout is 12 seconds
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 * If we are running ethereum.js inside ethereum browser, there are backend based tools responsible for polling,
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 * and provider manager polling mechanism is not used
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 */
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var ProviderManager = function() {
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    this.polls = [];
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    this.provider = undefined;
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    var self = this;
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    var poll = function () {
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        self.polls.forEach(function (data) {
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            var result = self.send(data.data);
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            if (!(result instanceof Array) || result.length === 0) {
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                return;
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            }
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            data.callback(result);
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        });
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        setTimeout(poll, 1000);
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    };
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    poll();
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};
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/// sends outgoing requests
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/// @params data - an object with at least 'method' property
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ProviderManager.prototype.send = function(data) {
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    var payload = jsonrpc.toPayload(data.method, data.params);
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    if (this.provider === undefined) {
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        console.error('provider is not set');
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        return null; 
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    }
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    var result = this.provider.send(payload);
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    if (!jsonrpc.isValidResponse(result)) {
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        console.log(result);
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        return null;
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    }
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    return result.result;
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};
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/// setups provider, which will be used for sending messages
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ProviderManager.prototype.set = function(provider) {
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    this.provider = provider;
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};
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/// this method is only used, when we do not have native qt bindings and have to do polling on our own
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/// should be callled, on start watching for eth/shh changes
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ProviderManager.prototype.startPolling = function (data, pollId, callback) {
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    this.polls.push({data: data, id: pollId, callback: callback});
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};
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/// should be called to stop polling for certain watch changes
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ProviderManager.prototype.stopPolling = function (pollId) {
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    for (var i = this.polls.length; i--;) {
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        var poll = this.polls[i];
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        if (poll.id === pollId) {
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            this.polls.splice(i, 1);
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        }
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    }
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};
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module.exports = ProviderManager;
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