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 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 | 1× 1× 1× 1× 51× 51× 51× 51× 51× 51× 1× 1× 1× 51× 51× 1× 51× 51× 51× 39× 51× 1× 51× 51× 51× 40× 11× 11× 11× 1× 165× 165× 1× 51× 51× 51× 51× 51× 37× 51× 51× 51× 51× 51× 51× 51× 51× 1× 32× 32× 32× 32× 1× 51× 51× 51× 51× 51× 51× 51× 51× 1× 1× 1× 2× 2× 2× 51× 12× 51× 51× 35× 35× 163× 163× 163× 163× 16× 147× 147× 147× 16× 16× 16× 51× 1× | /* This file is part of web3.js. web3.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. web3.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 web3.js. If not, see <http://www.gnu.org/licenses/>. */ /** * @file subscription.js * @author Fabian Vogelsteller <fabian@ethereum.org> * @date 2017 */ "use strict"; var _ = require('underscore'); var errors = require('web3-core-helpers').errors; var EventEmitter = require('eventemitter3'); function Subscription(options) { EventEmitter.call(this); this.id = null; this.callback = null; this.arguments = null; this._reconnectIntervalId = null; this.options = { subscription: options.subscription, type: options.type, requestManager: options.requestManager }; } // INHERIT Subscription.prototype = Object.create(EventEmitter.prototype); Subscription.prototype.constructor = Subscription; /** * Should be used to extract callback from array of arguments. Modifies input param * * @method extractCallback * @param {Array} arguments * @return {Function|Null} callback, if exists */ Subscription.prototype._extractCallback = function (args) { Eif (_.isFunction(args[args.length - 1])) { return args.pop(); // modify the args array! } }; /** * Should be called to check if the number of arguments is correct * * @method validateArgs * @param {Array} arguments * @throws {Error} if it is not */ Subscription.prototype._validateArgs = function (args) { var subscription = this.options.subscription; Iif(!subscription) subscription = {}; if(!subscription.params) subscription.params = 0; Iif (args.length !== subscription.params) { throw errors.InvalidNumberOfParams(args.length, subscription.params + 1, args[0]); } }; /** * Should be called to format input args of method * * @method formatInput * @param {Array} * @return {Array} */ Subscription.prototype._formatInput = function (args) { var subscription = this.options.subscription; Iif (!subscription) { return args; } if (!subscription.inputFormatter) { return args; } var formattedArgs = subscription.inputFormatter.map(function (formatter, index) { return formatter ? formatter(args[index]) : args[index]; }); return formattedArgs; }; /** * Should be called to format output(result) of method * * @method formatOutput * @param {Object} * @return {Object} */ Subscription.prototype._formatOutput = function (result) { var subscription = this.options.subscription; return (subscription && subscription.outputFormatter && result) ? subscription.outputFormatter(result) : result; }; /** * Should create payload from given input args * * @method toPayload * @param {Array} args * @return {Object} */ Subscription.prototype._toPayload = function (args) { var params = []; this.callback = this._extractCallback(args); Eif (!this.subscriptionMethod) { this.subscriptionMethod = args.shift(); // replace subscription with given name if (this.options.subscription.subscriptionName) { this.subscriptionMethod = this.options.subscription.subscriptionName; } } Eif (!this.arguments) { this.arguments = this._formatInput(args); this._validateArgs(this.arguments); args = []; // make empty after validation } // re-add subscriptionName params.push(this.subscriptionMethod); params = params.concat(this.arguments); Iif (args.length) { throw new Error('Only a callback is allowed as parameter on an already instantiated subscription.'); } return { method: this.options.type + '_subscribe', params: params }; }; /** * Unsubscribes and clears callbacks * * @method unsubscribe * @return {Object} */ Subscription.prototype.unsubscribe = function(callback) { this.options.requestManager.removeSubscription(this.id, callback); this.id = null; this.removeAllListeners(); clearInterval(this._reconnectIntervalId); }; /** * Subscribes and watches for changes * * @method subscribe * @param {String} subscription the subscription * @param {Object} options the options object with address topics and fromBlock * @return {Object} */ Subscription.prototype.subscribe = function() { var _this = this; var args = Array.prototype.slice.call(arguments); var payload = this._toPayload(args); Iif(!payload) { return this; } // throw error, if provider doesnt support subscriptions Iif(!this.options.requestManager.provider.on) { var err = new Error('The current provider doesn\'t support subscriptions'+ this.options.requestManager.provider.constructor.name); this.callback(err, null, this); this.emit('error', err); return this; } // if id is there unsubscribe first Iif (this.id) { this.unsubscribe(); } // store the params in the options object this.options.params = payload.params[1]; // get past logs, if fromBlock is available if(payload.params[0] === 'logs' && _.isObject(payload.params[1]) && payload.params[1].hasOwnProperty('fromBlock') && isFinite(payload.params[1].fromBlock)) { // send the subscription request this.options.requestManager.send({ method: 'eth_getLogs', params: [payload.params[1]] }, function (err, logs) { Eif(!err) { logs.forEach(function(log){ var output = _this._formatOutput(log); _this.callback(null, output, _this); _this.emit('data', output); }); // TODO subscribe here? after the past logs? } else { _this.callback(err, null, _this); _this.emit('error', err); } }); } // create subscription // TODO move to separate function? so that past logs can go first? if(typeof payload.params[1] === 'object') delete payload.params[1].fromBlock; this.options.requestManager.send(payload, function (err, result) { if(!err && result) { _this.id = result; // call callback on notifications _this.options.requestManager.addSubscription(_this.id, payload.params[0] , _this.options.type, function(err, result) { // TODO remove once its fixed in geth Iif(_.isArray(result)) result = result[0]; var output = _this._formatOutput(result); Eif (!err) { if(_.isFunction(_this.options.subscription.subscriptionHandler)) { return _this.options.subscription.subscriptionHandler.call(_this, output); } else { _this.emit('data', output); } } else { // unsubscribe, but keep listeners _this.options.requestManager.removeSubscription(_this.id); // re-subscribe, if connection fails if(_this.options.requestManager.provider.once) { _this._reconnectIntervalId = setInterval(function () { // TODO check if that makes sense! _this.options.requestManager.provider.reconnect(); }, 500); _this.options.requestManager.provider.once('connect', function () { clearInterval(_this._reconnectIntervalId); _this.subscribe(_this.callback); }); } _this.emit('error', err); } // call the callback, last so that unsubscribe there won't affect the emit above Eif (_.isFunction(_this.callback)) { _this.callback(err, output, _this); } }); } else Eif (_.isFunction(_this.callback)) { _this.callback(err, null, _this); _this.emit('error', err); } }); // return an object to cancel the subscription return this; }; module.exports = Subscription; |