server/models/request.js

   1 'use strict'
   2
   3 const async = require('async')
   4 const map = require('lodash/map')
   5 const mongoose = require('mongoose')
   6
   7 const constants = require('../initializers/constants')
   8 const logger = require('../helpers/logger')
   9 const requests = require('../helpers/requests')
  10
  11 const Pod = mongoose.model('Pod')
  12 const Video = mongoose.model('Video')
  13
  14 let timer = null
  15
  16 // ---------------------------------------------------------------------------
  17
  18 const RequestSchema = mongoose.Schema({
  19   request: mongoose.Schema.Types.Mixed,
  20   to: [ { type: mongoose.Schema.Types.ObjectId, ref: 'users' } ]
  21 })
  22
  23 RequestSchema.statics = {
  24   activate,
  25   deactivate,
  26   flush,
  27   forceSend
  28 }
  29
  30 RequestSchema.pre('save', function (next) {
  31   const self = this
  32
  33   if (self.to.length === 0) {
  34     Pod.listAllIds(function (err, podIds) {
  35       if (err) return next(err)
  36
  37       // No friends
  38       if (podIds.length === 0) return
  39
  40       self.to = podIds
  41       return next()
  42     })
  43   } else {
  44     return next()
  45   }
  46 })
  47
  48 mongoose.model('Request', RequestSchema)
  49
  50 // ------------------------------ STATICS ------------------------------
  51
  52 function activate () {
  53   logger.info('Requests scheduler activated.')
  54   timer = setInterval(makeRequests.bind(this), constants.INTERVAL)
  55 }
  56
  57 function deactivate () {
  58   logger.info('Requests scheduler deactivated.')
  59   clearInterval(timer)
  60 }
  61
  62 function flush () {
  63   removeAll.call(this, function (err) {
  64     if (err) logger.error('Cannot flush the requests.', { error: err })
  65   })
  66 }
  67
  68 function forceSend () {
  69   logger.info('Force requests scheduler sending.')
  70   makeRequests.call(this)
  71 }
  72
  73 // ---------------------------------------------------------------------------
  74
  75 // Make a requests to friends of a certain type
  76 function makeRequest (toPod, requestsToMake, callback) {
  77   if (!callback) callback = function () {}
  78
  79   const params = {
  80     toPod: toPod,
  81     encrypt: true, // Security
  82     sign: true, // To prove our identity
  83     method: 'POST',
  84     path: '/api/' + constants.API_VERSION + '/remote/videos',
  85     data: requestsToMake // Requests we need to make
  86   }
  87
  88   // Make multiple retry requests to all of pods
  89   // The function fire some useful callbacks
  90   requests.makeSecureRequest(params, function (err, res) {
  91     if (err || (res.statusCode !== 200 && res.statusCode !== 201 && res.statusCode !== 204)) {
  92       logger.error('Error sending secure request to %s pod.', toPod.url, { error: err || new Error('Status code not 20x') })
  93
  94       return callback(false)
  95     }
  96
  97     return callback(true)
  98   })
  99 }
 100
 101 // Make all the requests of the scheduler
 102 function makeRequests () {
 103   const self = this
 104
 105   listWithLimit.call(self, constants.REQUESTS_LIMIT, function (err, requests) {
 106     if (err) {
 107       logger.error('Cannot get the list of requests.', { err: err })
 108       return // Abort
 109     }
 110
 111     // If there are no requests, abort
 112     if (requests.length === 0) {
 113       logger.info('No requests to make.')
 114       return
 115     }
 116
 117     logger.info('Making requests to friends.')
 118
 119     // Requests by pods id
 120     const requestsToMake = {}
 121
 122     requests.forEach(function (poolRequest) {
 123       poolRequest.to.forEach(function (toPodId) {
 124         if (!requestsToMake[toPodId]) {
 125           requestsToMake[toPodId] = {
 126             ids: [],
 127             datas: []
 128           }
 129         }
 130
 131         requestsToMake[toPodId].ids.push(poolRequest._id)
 132         requestsToMake[toPodId].datas.push(poolRequest.request)
 133       })
 134     })
 135
 136     const goodPods = []
 137     const badPods = []
 138
 139     async.eachLimit(Object.keys(requestsToMake), constants.REQUESTS_IN_PARALLEL, function (toPodId, callbackEach) {
 140       const requestToMake = requestsToMake[toPodId]
 141
 142       // FIXME: mongodb request inside a loop :/
 143       Pod.load(toPodId, function (err, toPod) {
 144         if (err) {
 145           logger.error('Error finding pod by id.', { err: err })
 146           return callbackEach()
 147         }
 148
 149         // Maybe the pod is not our friend anymore so simply remove them
 150         if (!toPod) {
 151           removePodOf.call(self, requestToMake.ids, toPodId)
 152           return callbackEach()
 153         }
 154
 155         makeRequest(toPod, requestToMake.datas, function (success) {
 156           if (err) {
 157             logger.error('Errors when sent request to %s.', toPod.url, { error: err })
 158             // Do not stop the process just for one error
 159             return callbackEach()
 160           }
 161
 162           if (success === true) {
 163             logger.debug('Removing requests for %s pod.', toPodId, { requestsIds: requestToMake.ids })
 164
 165             // Remove the pod id of these request ids
 166             removePodOf.call(self, requestToMake.ids, toPodId)
 167             goodPods.push(toPodId)
 168           } else {
 169             badPods.push(toPodId)
 170           }
 171
 172           callbackEach()
 173         })
 174       })
 175     }, function () {
 176       // All the requests were made, we update the pods score
 177       updatePodsScore(goodPods, badPods)
 178       // Flush requests with no pod
 179       removeWithEmptyTo.call(self)
 180     })
 181   })
 182 }
 183
 184 // Remove pods with a score of 0 (too many requests where they were unreachable)
 185 function removeBadPods () {
 186   async.waterfall([
 187     function findBadPods (callback) {
 188       Pod.listBadPods(function (err, pods) {
 189         if (err) {
 190           logger.error('Cannot find bad pods.', { error: err })
 191           return callback(err)
 192         }
 193
 194         return callback(null, pods)
 195       })
 196     },
 197
 198     function listVideosOfTheseBadPods (pods, callback) {
 199       if (pods.length === 0) return callback(null)
 200
 201       const urls = map(pods, 'url')
 202
 203       Video.listByUrls(urls, function (err, videosList) {
 204         if (err) {
 205           logger.error('Cannot list videos urls.', { error: err, urls: urls })
 206           return callback(null, pods, [])
 207         }
 208
 209         return callback(null, pods, videosList)
 210       })
 211     },
 212
 213     function removeVideosOfTheseBadPods (pods, videosList, callback) {
 214       // We don't have to remove pods, skip
 215       if (typeof pods === 'function') {
 216         callback = pods
 217         return callback(null)
 218       }
 219
 220       async.each(videosList, function (video, callbackEach) {
 221         video.remove(callbackEach)
 222       }, function (err) {
 223         if (err) {
 224           // Don't stop the process
 225           logger.error('Error while removing videos of bad pods.', { error: err })
 226           return
 227         }
 228
 229         return callback(null, pods)
 230       })
 231     },
 232
 233     function removeBadPodsFromDB (pods, callback) {
 234       // We don't have to remove pods, skip
 235       if (typeof pods === 'function') {
 236         callback = pods
 237         return callback(null)
 238       }
 239
 240       async.each(pods, function (pod, callbackEach) {
 241         pod.remove(callbackEach)
 242       }, function (err) {
 243         if (err) return callback(err)
 244
 245         return callback(null, pods.length)
 246       })
 247     }
 248   ], function (err, numberOfPodsRemoved) {
 249     if (err) {
 250       logger.error('Cannot remove bad pods.', { error: err })
 251     } else if (numberOfPodsRemoved) {
 252       logger.info('Removed %d pods.', numberOfPodsRemoved)
 253     } else {
 254       logger.info('No need to remove bad pods.')
 255     }
 256   })
 257 }
 258
 259 function updatePodsScore (goodPods, badPods) {
 260   logger.info('Updating %d good pods and %d bad pods scores.', goodPods.length, badPods.length)
 261
 262   Pod.incrementScores(goodPods, constants.PODS_SCORE.BONUS, function (err) {
 263     if (err) logger.error('Cannot increment scores of good pods.')
 264   })
 265
 266   Pod.incrementScores(badPods, constants.PODS_SCORE.MALUS, function (err) {
 267     if (err) logger.error('Cannot decrement scores of bad pods.')
 268     removeBadPods()
 269   })
 270 }
 271
 272 function listWithLimit (limit, callback) {
 273   this.find({ }, { _id: 1, request: 1, to: 1 }).sort({ _id: 1 }).limit(limit).exec(callback)
 274 }
 275
 276 function removeAll (callback) {
 277   this.remove({ }, callback)
 278 }
 279
 280 function removePodOf (requestsIds, podId, callback) {
 281   if (!callback) callback = function () {}
 282
 283   this.update({ _id: { $in: requestsIds } }, { $pull: { to: podId } }, { multi: true }, callback)
 284 }
 285
 286 function removeWithEmptyTo (callback) {
 287   if (!callback) callback = function () {}
 288
 289   this.remove({ to: { $size: 0 } }, callback)
 290 }