The Tor Browser: dom/network/src/NetworkStatsDB.jsm@b8a032363ba2 (annotated)

dom/network/src/NetworkStatsDB.jsm@b8a032363ba2 (annotated)

dom/network/src/NetworkStatsDB.jsm

Thu, 22 Jan 2015 13:21:57 +0100

author: Michael Schloh von Bennewitz <michael@schloh.com>
date: Thu, 22 Jan 2015 13:21:57 +0100
branch: TOR_BUG_9701
changeset 15: b8a032363ba2
permissions: -rw-r--r--

Incorporate requested changes from Mozilla in review:
https://bugzilla.mozilla.org/show_bug.cgi?id=1123480#c6

 /* This Source Code Form is subject to the terms of the Mozilla Public
  * License, v. 2.0. If a copy of the MPL was not distributed with this file,
  * You can obtain one at http://mozilla.org/MPL/2.0/. */
 "use strict";
 this.EXPORTED_SYMBOLS = ['NetworkStatsDB'];
 const DEBUG = false;
 function debug(s) { dump("-*- NetworkStatsDB: " + s + "\n"); }
 const {classes: Cc, interfaces: Ci, utils: Cu, results: Cr} = Components;
 Cu.import("resource://gre/modules/Services.jsm");
 Cu.import("resource://gre/modules/IndexedDBHelper.jsm");
 Cu.importGlobalProperties(["indexedDB"]);
 const DB_NAME = "net_stats";
 const DB_VERSION = 8;
 const DEPRECATED_STORE_NAME = "net_stats";
 const STATS_STORE_NAME = "net_stats_store";
 const ALARMS_STORE_NAME = "net_alarm";
 // Constant defining the maximum values allowed per interface. If more, older
 // will be erased.
 const VALUES_MAX_LENGTH = 6 * 30;
 // Constant defining the rate of the samples. Daily.
 const SAMPLE_RATE = 1000 * 60 * 60 * 24;
 this.NetworkStatsDB = function NetworkStatsDB() {
   if (DEBUG) {
     debug("Constructor");
   }
   this.initDBHelper(DB_NAME, DB_VERSION, [STATS_STORE_NAME, ALARMS_STORE_NAME]);
 }
 NetworkStatsDB.prototype = {
   __proto__: IndexedDBHelper.prototype,
   dbNewTxn: function dbNewTxn(store_name, txn_type, callback, txnCb) {
     function successCb(result) {
       txnCb(null, result);
     }
     function errorCb(error) {
       txnCb(error, null);
     }
     return this.newTxn(txn_type, store_name, callback, successCb, errorCb);
   },
   upgradeSchema: function upgradeSchema(aTransaction, aDb, aOldVersion, aNewVersion) {
     if (DEBUG) {
       debug("upgrade schema from: " + aOldVersion + " to " + aNewVersion + " called!");
     }
     let db = aDb;
     let objectStore;
     for (let currVersion = aOldVersion; currVersion < aNewVersion; currVersion++) {
       if (currVersion == 0) {
         /**
          * Create the initial database schema.
          */
         objectStore = db.createObjectStore(DEPRECATED_STORE_NAME, { keyPath: ["connectionType", "timestamp"] });
         objectStore.createIndex("connectionType", "connectionType", { unique: false });
         objectStore.createIndex("timestamp", "timestamp", { unique: false });
         objectStore.createIndex("rxBytes", "rxBytes", { unique: false });
         objectStore.createIndex("txBytes", "txBytes", { unique: false });
         objectStore.createIndex("rxTotalBytes", "rxTotalBytes", { unique: false });
         objectStore.createIndex("txTotalBytes", "txTotalBytes", { unique: false });
         if (DEBUG) {
           debug("Created object stores and indexes");
         }
       } else if (currVersion == 2) {
         // In order to support per-app traffic data storage, the original
         // objectStore needs to be replaced by a new objectStore with new
         // key path ("appId") and new index ("appId").
         // Also, since now networks are identified by their
         // [networkId, networkType] not just by their connectionType,
         // to modify the keyPath is mandatory to delete the object store
         // and create it again. Old data is going to be deleted because the
         // networkId for each sample can not be set.
         // In version 1.2 objectStore name was 'net_stats_v2', to avoid errors when
         // upgrading from 1.2 to 1.3 objectStore name should be checked.
         let stores = db.objectStoreNames;
         if(stores.contains("net_stats_v2")) {
           db.deleteObjectStore("net_stats_v2");
         } else {
           db.deleteObjectStore(DEPRECATED_STORE_NAME);
         }
         objectStore = db.createObjectStore(DEPRECATED_STORE_NAME, { keyPath: ["appId", "network", "timestamp"] });
         objectStore.createIndex("appId", "appId", { unique: false });
         objectStore.createIndex("network", "network", { unique: false });
         objectStore.createIndex("networkType", "networkType", { unique: false });
         objectStore.createIndex("timestamp", "timestamp", { unique: false });
         objectStore.createIndex("rxBytes", "rxBytes", { unique: false });
         objectStore.createIndex("txBytes", "txBytes", { unique: false });
         objectStore.createIndex("rxTotalBytes", "rxTotalBytes", { unique: false });
         objectStore.createIndex("txTotalBytes", "txTotalBytes", { unique: false });
         if (DEBUG) {
           debug("Created object stores and indexes for version 3");
         }
       } else if (currVersion == 3) {
         // Delete redundent indexes (leave "network" only).
         objectStore = aTransaction.objectStore(DEPRECATED_STORE_NAME);
         if (objectStore.indexNames.contains("appId")) {
           objectStore.deleteIndex("appId");
         }
         if (objectStore.indexNames.contains("networkType")) {
           objectStore.deleteIndex("networkType");
         }
         if (objectStore.indexNames.contains("timestamp")) {
           objectStore.deleteIndex("timestamp");
         }
         if (objectStore.indexNames.contains("rxBytes")) {
           objectStore.deleteIndex("rxBytes");
         }
         if (objectStore.indexNames.contains("txBytes")) {
           objectStore.deleteIndex("txBytes");
         }
         if (objectStore.indexNames.contains("rxTotalBytes")) {
           objectStore.deleteIndex("rxTotalBytes");
         }
         if (objectStore.indexNames.contains("txTotalBytes")) {
           objectStore.deleteIndex("txTotalBytes");
         }
         if (DEBUG) {
           debug("Deleted redundent indexes for version 4");
         }
       } else if (currVersion == 4) {
         // In order to manage alarms, it is necessary to use a global counter
         // (totalBytes) that will increase regardless of the system reboot.
         objectStore = aTransaction.objectStore(DEPRECATED_STORE_NAME);
         // Now, systemBytes will hold the old totalBytes and totalBytes will
         // keep the increasing counter. |counters| will keep the track of
         // accumulated values.
         let counters = {};
         objectStore.openCursor().onsuccess = function(event) {
           let cursor = event.target.result;
           if (!cursor){
             return;
           }
           cursor.value.rxSystemBytes = cursor.value.rxTotalBytes;
           cursor.value.txSystemBytes = cursor.value.txTotalBytes;
           if (cursor.value.appId == 0) {
             let netId = cursor.value.network[0] + '' + cursor.value.network[1];
             if (!counters[netId]) {
               counters[netId] = {
                 rxCounter: 0,
                 txCounter: 0,
                 lastRx: 0,
                 lastTx: 0
               };
             }
             let rxDiff = cursor.value.rxSystemBytes - counters[netId].lastRx;
             let txDiff = cursor.value.txSystemBytes - counters[netId].lastTx;
             if (rxDiff < 0 || txDiff < 0) {
               // System reboot between samples, so take the current one.
               rxDiff = cursor.value.rxSystemBytes;
               txDiff = cursor.value.txSystemBytes;
             }
             counters[netId].rxCounter += rxDiff;
             counters[netId].txCounter += txDiff;
             cursor.value.rxTotalBytes = counters[netId].rxCounter;
             cursor.value.txTotalBytes = counters[netId].txCounter;
             counters[netId].lastRx = cursor.value.rxSystemBytes;
             counters[netId].lastTx = cursor.value.txSystemBytes;
           } else {
             cursor.value.rxTotalBytes = cursor.value.rxSystemBytes;
             cursor.value.txTotalBytes = cursor.value.txSystemBytes;
           }
           cursor.update(cursor.value);
           cursor.continue();
         };
         // Create object store for alarms.
         objectStore = db.createObjectStore(ALARMS_STORE_NAME, { keyPath: "id", autoIncrement: true });
         objectStore.createIndex("alarm", ['networkId','threshold'], { unique: false });
         objectStore.createIndex("manifestURL", "manifestURL", { unique: false });
         if (DEBUG) {
           debug("Created alarms store for version 5");
         }
       } else if (currVersion == 5) {
         // In contrast to "per-app" traffic data, "system-only" traffic data
         // refers to data which can not be identified by any applications.
         // To further support "system-only" data storage, the data can be
         // saved by service type (e.g., Tethering, OTA). Thus it's needed to
         // have a new key ("serviceType") for the ojectStore.
         let newObjectStore;
         newObjectStore = db.createObjectStore(STATS_STORE_NAME,
                          { keyPath: ["appId", "serviceType", "network", "timestamp"] });
         newObjectStore.createIndex("network", "network", { unique: false });
         // Copy the data from the original objectStore to the new objectStore.
         objectStore = aTransaction.objectStore(DEPRECATED_STORE_NAME);
         objectStore.openCursor().onsuccess = function(event) {
           let cursor = event.target.result;
           if (!cursor) {
             db.deleteObjectStore(DEPRECATED_STORE_NAME);
             return;
           }
           let newStats = cursor.value;
           newStats.serviceType = "";
           newObjectStore.put(newStats);
           cursor.continue();
         };
         if (DEBUG) {
           debug("Added new key 'serviceType' for version 6");
         }
       } else if (currVersion == 6) {
         // Replace threshold attribute of alarm index by relativeThreshold in alarms DB.
         // Now alarms are indexed by relativeThreshold, which is the threshold relative
         // to current system stats.
         let alarmsStore = aTransaction.objectStore(ALARMS_STORE_NAME);
         // Delete "alarm" index.
         if (alarmsStore.indexNames.contains("alarm")) {
           alarmsStore.deleteIndex("alarm");
         }
         // Create new "alarm" index.
         alarmsStore.createIndex("alarm", ['networkId','relativeThreshold'], { unique: false });
         // Populate new "alarm" index attributes.
         alarmsStore.openCursor().onsuccess = function(event) {
           let cursor = event.target.result;
           if (!cursor) {
             return;
           }
           cursor.value.relativeThreshold = cursor.value.threshold;
           cursor.value.absoluteThreshold = cursor.value.threshold;
           delete cursor.value.threshold;
           cursor.update(cursor.value);
           cursor.continue();
         }
         // Previous versions save accumulative totalBytes, increasing althought the system
         // reboots or resets stats. But is necessary to reset the total counters when reset
         // through 'clearInterfaceStats'.
         let statsStore = aTransaction.objectStore(STATS_STORE_NAME);
         let networks = [];
         // Find networks stored in the database.
         statsStore.index("network").openKeyCursor(null, "nextunique").onsuccess = function(event) {
           let cursor = event.target.result;
           if (cursor) {
             networks.push(cursor.key);
             cursor.continue();
             return;
           }
           networks.forEach(function(network) {
             let lowerFilter = [0, "", network, 0];
             let upperFilter = [0, "", network, ""];
             let range = IDBKeyRange.bound(lowerFilter, upperFilter, false, false);
             // Find number of samples for a given network.
             statsStore.count(range).onsuccess = function(event) {
               // If there are more samples than the max allowed, there is no way to know
               // when does reset take place.
               if (event.target.result >= VALUES_MAX_LENGTH) {
                 return;
               }
               let last = null;
               // Reset detected if the first sample totalCounters are different than bytes
               // counters. If so, the total counters should be recalculated.
               statsStore.openCursor(range).onsuccess = function(event) {
                 let cursor = event.target.result;
                 if (!cursor) {
                   return;
                 }
                 if (!last) {
                   if (cursor.value.rxTotalBytes == cursor.value.rxBytes &&
                       cursor.value.txTotalBytes == cursor.value.txBytes) {
                     return;
                   }
                   cursor.value.rxTotalBytes = cursor.value.rxBytes;
                   cursor.value.txTotalBytes = cursor.value.txBytes;
                   cursor.update(cursor.value);
                   last = cursor.value;
                   cursor.continue();
                   return;
                 }
                 // Recalculate the total counter for last / current sample
                 cursor.value.rxTotalBytes = last.rxTotalBytes + cursor.value.rxBytes;
                 cursor.value.txTotalBytes = last.txTotalBytes + cursor.value.txBytes;
                 cursor.update(cursor.value);
                 last = cursor.value;
                 cursor.continue();
               }
             }
           }, this);
         };
       } else if (currVersion == 7) {
         // Create index for 'ServiceType' in order to make it retrievable.
         let statsStore = aTransaction.objectStore(STATS_STORE_NAME);
         statsStore.createIndex("serviceType", "serviceType", { unique: false });
         if (DEBUG) {
           debug("Create index of 'serviceType' for version 8");
         }
       }
     }
   },
   importData: function importData(aStats) {
     let stats = { appId:         aStats.appId,
                   serviceType:   aStats.serviceType,
                   network:       [aStats.networkId, aStats.networkType],
                   timestamp:     aStats.timestamp,
                   rxBytes:       aStats.rxBytes,
                   txBytes:       aStats.txBytes,
                   rxSystemBytes: aStats.rxSystemBytes,
                   txSystemBytes: aStats.txSystemBytes,
                   rxTotalBytes:  aStats.rxTotalBytes,
                   txTotalBytes:  aStats.txTotalBytes };
     return stats;
   },
   exportData: function exportData(aStats) {
     let stats = { appId:        aStats.appId,
                   serviceType:  aStats.serviceType,
                   networkId:    aStats.network[0],
                   networkType:  aStats.network[1],
                   timestamp:    aStats.timestamp,
                   rxBytes:      aStats.rxBytes,
                   txBytes:      aStats.txBytes,
                   rxTotalBytes: aStats.rxTotalBytes,
                   txTotalBytes: aStats.txTotalBytes };
     return stats;
   },
   normalizeDate: function normalizeDate(aDate) {
     // Convert to UTC according to timezone and
     // filter timestamp to get SAMPLE_RATE precission
     let timestamp = aDate.getTime() - aDate.getTimezoneOffset() * 60 * 1000;
     timestamp = Math.floor(timestamp / SAMPLE_RATE) * SAMPLE_RATE;
     return timestamp;
   },
   saveStats: function saveStats(aStats, aResultCb) {
     let isAccumulative = aStats.isAccumulative;
     let timestamp = this.normalizeDate(aStats.date);
     let stats = { appId:         aStats.appId,
                   serviceType:   aStats.serviceType,
                   networkId:     aStats.networkId,
                   networkType:   aStats.networkType,
                   timestamp:     timestamp,
                   rxBytes:       (isAccumulative) ? 0 : aStats.rxBytes,
                   txBytes:       (isAccumulative) ? 0 : aStats.txBytes,
                   rxSystemBytes: (isAccumulative) ? aStats.rxBytes : 0,
                   txSystemBytes: (isAccumulative) ? aStats.txBytes : 0,
                   rxTotalBytes:  (isAccumulative) ? aStats.rxBytes : 0,
                   txTotalBytes:  (isAccumulative) ? aStats.txBytes : 0 };
     stats = this.importData(stats);
     this.dbNewTxn(STATS_STORE_NAME, "readwrite", function(aTxn, aStore) {
       if (DEBUG) {
         debug("Filtered time: " + new Date(timestamp));
         debug("New stats: " + JSON.stringify(stats));
       }
       let request = aStore.index("network").openCursor(stats.network, "prev");
       request.onsuccess = function onsuccess(event) {
         let cursor = event.target.result;
         if (!cursor) {
           // Empty, so save first element.
           // There could be a time delay between the point when the network
           // interface comes up and the point when the database is initialized.
           // In this short interval some traffic data are generated but are not
           // registered by the first sample.
           if (isAccumulative) {
             stats.rxBytes = stats.rxTotalBytes;
             stats.txBytes = stats.txTotalBytes;
           }
           this._saveStats(aTxn, aStore, stats);
           return;
         }
         let value = cursor.value;
         if (stats.appId != value.appId ||
             (stats.appId == 0 && stats.serviceType != value.serviceType)) {
           cursor.continue();
           return;
         }
         // There are old samples
         if (DEBUG) {
           debug("Last value " + JSON.stringify(value));
         }
         // Remove stats previous to now - VALUE_MAX_LENGTH
         this._removeOldStats(aTxn, aStore, stats.appId, stats.serviceType,
                              stats.network, stats.timestamp);
         // Process stats before save
         this._processSamplesDiff(aTxn, aStore, cursor, stats, isAccumulative);
       }.bind(this);
     }.bind(this), aResultCb);
   },
   /*
    * This function check that stats are saved in the database following the sample rate.
    * In this way is easier to find elements when stats are requested.
    */
   _processSamplesDiff: function _processSamplesDiff(aTxn,
                                                     aStore,
                                                     aLastSampleCursor,
                                                     aNewSample,
                                                     aIsAccumulative) {
     let lastSample = aLastSampleCursor.value;
     // Get difference between last and new sample.
     let diff = (aNewSample.timestamp - lastSample.timestamp) / SAMPLE_RATE;
     if (diff % 1) {
       // diff is decimal, so some error happened because samples are stored as a multiple
       // of SAMPLE_RATE
       aTxn.abort();
       throw new Error("Error processing samples");
     }
     if (DEBUG) {
       debug("New: " + aNewSample.timestamp + " - Last: " +
             lastSample.timestamp + " - diff: " + diff);
     }
     // If the incoming data has a accumulation feature, the new
     // |txBytes|/|rxBytes| is assigend by differnces between the new
     // |txTotalBytes|/|rxTotalBytes| and the last |txTotalBytes|/|rxTotalBytes|.
     // Else, if incoming data is non-accumulative, the |txBytes|/|rxBytes|
     // is the new |txBytes|/|rxBytes|.
     let rxDiff = 0;
     let txDiff = 0;
     if (aIsAccumulative) {
       rxDiff = aNewSample.rxSystemBytes - lastSample.rxSystemBytes;
       txDiff = aNewSample.txSystemBytes - lastSample.txSystemBytes;
       if (rxDiff < 0 || txDiff < 0) {
         rxDiff = aNewSample.rxSystemBytes;
         txDiff = aNewSample.txSystemBytes;
       }
       aNewSample.rxBytes = rxDiff;
       aNewSample.txBytes = txDiff;
       aNewSample.rxTotalBytes = lastSample.rxTotalBytes + rxDiff;
       aNewSample.txTotalBytes = lastSample.txTotalBytes + txDiff;
     } else {
       rxDiff = aNewSample.rxBytes;
       txDiff = aNewSample.txBytes;
     }
     if (diff == 1) {
       // New element.
       // If the incoming data is non-accumulative, the new
       // |rxTotalBytes|/|txTotalBytes| needs to be updated by adding new
       // |rxBytes|/|txBytes| to the last |rxTotalBytes|/|txTotalBytes|.
       if (!aIsAccumulative) {
         aNewSample.rxTotalBytes = aNewSample.rxBytes + lastSample.rxTotalBytes;
         aNewSample.txTotalBytes = aNewSample.txBytes + lastSample.txTotalBytes;
       }
       this._saveStats(aTxn, aStore, aNewSample);
       return;
     }
     if (diff > 1) {
       // Some samples lost. Device off during one or more samplerate periods.
       // Time or timezone changed
       // Add lost samples with 0 bytes and the actual one.
       if (diff > VALUES_MAX_LENGTH) {
         diff = VALUES_MAX_LENGTH;
       }
       let data = [];
       for (let i = diff - 2; i >= 0; i--) {
         let time = aNewSample.timestamp - SAMPLE_RATE * (i + 1);
         let sample = { appId:         aNewSample.appId,
                        serviceType:   aNewSample.serviceType,
                        network:       aNewSample.network,
                        timestamp:     time,
                        rxBytes:       0,
                        txBytes:       0,
                        rxSystemBytes: lastSample.rxSystemBytes,
                        txSystemBytes: lastSample.txSystemBytes,
                        rxTotalBytes:  lastSample.rxTotalBytes,
                        txTotalBytes:  lastSample.txTotalBytes };
         data.push(sample);
       }
       data.push(aNewSample);
       this._saveStats(aTxn, aStore, data);
       return;
     }
     if (diff == 0 || diff < 0) {
       // New element received before samplerate period. It means that device has
       // been restarted (or clock / timezone change).
       // Update element. If diff < 0, clock or timezone changed back. Place data
       // in the last sample.
       // Old |rxTotalBytes|/|txTotalBytes| needs to get updated by adding the
       // last |rxTotalBytes|/|txTotalBytes|.
       lastSample.rxBytes += rxDiff;
       lastSample.txBytes += txDiff;
       lastSample.rxSystemBytes = aNewSample.rxSystemBytes;
       lastSample.txSystemBytes = aNewSample.txSystemBytes;
       lastSample.rxTotalBytes += rxDiff;
       lastSample.txTotalBytes += txDiff;
       if (DEBUG) {
         debug("Update: " + JSON.stringify(lastSample));
       }
       let req = aLastSampleCursor.update(lastSample);
     }
   },
   _saveStats: function _saveStats(aTxn, aStore, aNetworkStats) {
     if (DEBUG) {
       debug("_saveStats: " + JSON.stringify(aNetworkStats));
     }
     if (Array.isArray(aNetworkStats)) {
       let len = aNetworkStats.length - 1;
       for (let i = 0; i <= len; i++) {
         aStore.put(aNetworkStats[i]);
       }
     } else {
       aStore.put(aNetworkStats);
     }
   },
   _removeOldStats: function _removeOldStats(aTxn, aStore, aAppId, aServiceType,
                                             aNetwork, aDate) {
     // Callback function to remove old items when new ones are added.
     let filterDate = aDate - (SAMPLE_RATE * VALUES_MAX_LENGTH - 1);
     let lowerFilter = [aAppId, aServiceType, aNetwork, 0];
     let upperFilter = [aAppId, aServiceType, aNetwork, filterDate];
     let range = IDBKeyRange.bound(lowerFilter, upperFilter, false, false);
     let lastSample = null;
     let self = this;
     aStore.openCursor(range).onsuccess = function(event) {
       var cursor = event.target.result;
       if (cursor) {
         lastSample = cursor.value;
         cursor.delete();
         cursor.continue();
         return;
       }
       // If all samples for a network are removed, an empty sample
       // has to be saved to keep the totalBytes in order to compute
       // future samples because system counters are not set to 0.
       // Thus, if there are no samples left, the last sample removed
       // will be saved again after setting its bytes to 0.
       let request = aStore.index("network").openCursor(aNetwork);
       request.onsuccess = function onsuccess(event) {
         let cursor = event.target.result;
         if (!cursor && lastSample != null) {
           let timestamp = new Date();
           timestamp = self.normalizeDate(timestamp);
           lastSample.timestamp = timestamp;
           lastSample.rxBytes = 0;
           lastSample.txBytes = 0;
           self._saveStats(aTxn, aStore, lastSample);
         }
       };
     };
   },
   clearInterfaceStats: function clearInterfaceStats(aNetwork, aResultCb) {
     let network = [aNetwork.network.id, aNetwork.network.type];
     let self = this;
     // Clear and save an empty sample to keep sync with system counters
     this.dbNewTxn(STATS_STORE_NAME, "readwrite", function(aTxn, aStore) {
       let sample = null;
       let request = aStore.index("network").openCursor(network, "prev");
       request.onsuccess = function onsuccess(event) {
         let cursor = event.target.result;
         if (cursor) {
           if (!sample && cursor.value.appId == 0) {
             sample = cursor.value;
           }
           cursor.delete();
           cursor.continue();
           return;
         }
         if (sample) {
           let timestamp = new Date();
           timestamp = self.normalizeDate(timestamp);
           sample.timestamp = timestamp;
           sample.appId = 0;
           sample.serviceType = "";
           sample.rxBytes = 0;
           sample.txBytes = 0;
           sample.rxTotalBytes = 0;
           sample.txTotalBytes = 0;
           self._saveStats(aTxn, aStore, sample);
         }
       };
     }, this._resetAlarms.bind(this, aNetwork.networkId, aResultCb));
   },
   clearStats: function clearStats(aNetworks, aResultCb) {
     let index = 0;
     let stats = [];
     let self = this;
     let callback = function(aError, aResult) {
       index++;
       if (!aError && index < aNetworks.length) {
         self.clearInterfaceStats(aNetworks[index], callback);
         return;
       }
       aResultCb(aError, aResult);
     };
     if (!aNetworks[index]) {
       aResultCb(null, true);
       return;
     }
     this.clearInterfaceStats(aNetworks[index], callback);
   },
   getCurrentStats: function getCurrentStats(aNetwork, aDate, aResultCb) {
     if (DEBUG) {
       debug("Get current stats for " + JSON.stringify(aNetwork) + " since " + aDate);
     }
     let network = [aNetwork.id, aNetwork.type];
     if (aDate) {
       this._getCurrentStatsFromDate(network, aDate, aResultCb);
       return;
     }
     this._getCurrentStats(network, aResultCb);
   },
   _getCurrentStats: function _getCurrentStats(aNetwork, aResultCb) {
     this.dbNewTxn(STATS_STORE_NAME, "readonly", function(txn, store) {
       let request = null;
       let upperFilter = [0, "", aNetwork, Date.now()];
       let range = IDBKeyRange.upperBound(upperFilter, false);
       request = store.openCursor(range, "prev");
       let result = { rxBytes:      0, txBytes:      0,
                      rxTotalBytes: 0, txTotalBytes: 0 };
       request.onsuccess = function onsuccess(event) {
         let cursor = event.target.result;
         if (cursor) {
           result.rxBytes = result.rxTotalBytes = cursor.value.rxTotalBytes;
           result.txBytes = result.txTotalBytes = cursor.value.txTotalBytes;
         }
         txn.result = result;
       };
     }.bind(this), aResultCb);
   },
   _getCurrentStatsFromDate: function _getCurrentStatsFromDate(aNetwork, aDate, aResultCb) {
     aDate = new Date(aDate);
     this.dbNewTxn(STATS_STORE_NAME, "readonly", function(txn, store) {
       let request = null;
       let start = this.normalizeDate(aDate);
       let lowerFilter = [0, "", aNetwork, start];
       let upperFilter = [0, "", aNetwork, Date.now()];
       let range = IDBKeyRange.upperBound(upperFilter, false);
       let result = { rxBytes:      0, txBytes:      0,
                      rxTotalBytes: 0, txTotalBytes: 0 };
       request = store.openCursor(range, "prev");
       request.onsuccess = function onsuccess(event) {
         let cursor = event.target.result;
         if (cursor) {
           result.rxBytes = result.rxTotalBytes = cursor.value.rxTotalBytes;
           result.txBytes = result.txTotalBytes = cursor.value.txTotalBytes;
         }
         let timestamp = cursor.value.timestamp;
         let range = IDBKeyRange.lowerBound(lowerFilter, false);
         request = store.openCursor(range);
         request.onsuccess = function onsuccess(event) {
           let cursor = event.target.result;
           if (cursor) {
             if (cursor.value.timestamp == timestamp) {
               // There is one sample only.
               result.rxBytes = cursor.value.rxBytes;
               result.txBytes = cursor.value.txBytes;
             } else {
               result.rxBytes -= cursor.value.rxTotalBytes;
               result.txBytes -= cursor.value.txTotalBytes;
             }
           }
           txn.result = result;
         };
       };
     }.bind(this), aResultCb);
   },
   find: function find(aResultCb, aAppId, aServiceType, aNetwork,
                       aStart, aEnd, aAppManifestURL) {
     let offset = (new Date()).getTimezoneOffset() * 60 * 1000;
     let start = this.normalizeDate(aStart);
     let end = this.normalizeDate(aEnd);
     if (DEBUG) {
       debug("Find samples for appId: " + aAppId + " serviceType: " +
             aServiceType + " network: " + JSON.stringify(aNetwork) + " from " +
             start + " until " + end);
       debug("Start time: " + new Date(start));
       debug("End time: " + new Date(end));
     }
     this.dbNewTxn(STATS_STORE_NAME, "readonly", function(aTxn, aStore) {
       let network = [aNetwork.id, aNetwork.type];
       let lowerFilter = [aAppId, aServiceType, network, start];
       let upperFilter = [aAppId, aServiceType, network, end];
       let range = IDBKeyRange.bound(lowerFilter, upperFilter, false, false);
       let data = [];
       if (!aTxn.result) {
         aTxn.result = {};
       }
       let request = aStore.openCursor(range).onsuccess = function(event) {
         var cursor = event.target.result;
         if (cursor){
           data.push({ rxBytes: cursor.value.rxBytes,
                       txBytes: cursor.value.txBytes,
                       date: new Date(cursor.value.timestamp + offset) });
           cursor.continue();
           return;
         }
         // When requested samples (start / end) are not in the range of now and
         // now - VALUES_MAX_LENGTH, fill with empty samples.
         this.fillResultSamples(start + offset, end + offset, data);
         aTxn.result.appManifestURL = aAppManifestURL;
         aTxn.result.serviceType = aServiceType;
         aTxn.result.network = aNetwork;
         aTxn.result.start = aStart;
         aTxn.result.end = aEnd;
         aTxn.result.data = data;
       }.bind(this);
     }.bind(this), aResultCb);
   },
   /*
    * Fill data array (samples from database) with empty samples to match
    * requested start / end dates.
    */
   fillResultSamples: function fillResultSamples(aStart, aEnd, aData) {
     if (aData.length == 0) {
       aData.push({ rxBytes: undefined,
                   txBytes: undefined,
                   date: new Date(aStart) });
     }
     while (aStart < aData[0].date.getTime()) {
       aData.unshift({ rxBytes: undefined,
                       txBytes: undefined,
                       date: new Date(aData[0].date.getTime() - SAMPLE_RATE) });
     }
     while (aEnd > aData[aData.length - 1].date.getTime()) {
       aData.push({ rxBytes: undefined,
                    txBytes: undefined,
                    date: new Date(aData[aData.length - 1].date.getTime() + SAMPLE_RATE) });
     }
   },
   getAvailableNetworks: function getAvailableNetworks(aResultCb) {
     this.dbNewTxn(STATS_STORE_NAME, "readonly", function(aTxn, aStore) {
       if (!aTxn.result) {
         aTxn.result = [];
       }
       let request = aStore.index("network").openKeyCursor(null, "nextunique");
       request.onsuccess = function onsuccess(event) {
         let cursor = event.target.result;
         if (cursor) {
           aTxn.result.push({ id: cursor.key[0],
                              type: cursor.key[1] });
           cursor.continue();
           return;
         }
       };
     }, aResultCb);
   },
   isNetworkAvailable: function isNetworkAvailable(aNetwork, aResultCb) {
     this.dbNewTxn(STATS_STORE_NAME, "readonly", function(aTxn, aStore) {
       if (!aTxn.result) {
         aTxn.result = false;
       }
       let network = [aNetwork.id, aNetwork.type];
       let request = aStore.index("network").openKeyCursor(IDBKeyRange.only(network));
       request.onsuccess = function onsuccess(event) {
         if (event.target.result) {
           aTxn.result = true;
         }
       };
     }, aResultCb);
   },
   getAvailableServiceTypes: function getAvailableServiceTypes(aResultCb) {
     this.dbNewTxn(STATS_STORE_NAME, "readonly", function(aTxn, aStore) {
       if (!aTxn.result) {
         aTxn.result = [];
       }
       let request = aStore.index("serviceType").openKeyCursor(null, "nextunique");
       request.onsuccess = function onsuccess(event) {
         let cursor = event.target.result;
         if (cursor && cursor.key != "") {
           aTxn.result.push({ serviceType: cursor.key });
           cursor.continue();
           return;
         }
       };
     }, aResultCb);
   },
   get sampleRate () {
     return SAMPLE_RATE;
   },
   get maxStorageSamples () {
     return VALUES_MAX_LENGTH;
   },
   logAllRecords: function logAllRecords(aResultCb) {
     this.dbNewTxn(STATS_STORE_NAME, "readonly", function(aTxn, aStore) {
       aStore.mozGetAll().onsuccess = function onsuccess(event) {
         aTxn.result = event.target.result;
       };
     }, aResultCb);
   },
   alarmToRecord: function alarmToRecord(aAlarm) {
     let record = { networkId: aAlarm.networkId,
                    absoluteThreshold: aAlarm.absoluteThreshold,
                    relativeThreshold: aAlarm.relativeThreshold,
                    startTime: aAlarm.startTime,
                    data: aAlarm.data,
                    manifestURL: aAlarm.manifestURL,
                    pageURL: aAlarm.pageURL };
     if (aAlarm.id) {
       record.id = aAlarm.id;
     }
     return record;
   },
   recordToAlarm: function recordToalarm(aRecord) {
     let alarm = { networkId: aRecord.networkId,
                   absoluteThreshold: aRecord.absoluteThreshold,
                   relativeThreshold: aRecord.relativeThreshold,
                   startTime: aRecord.startTime,
                   data: aRecord.data,
                   manifestURL: aRecord.manifestURL,
                   pageURL: aRecord.pageURL };
     if (aRecord.id) {
       alarm.id = aRecord.id;
     }
     return alarm;
   },
   addAlarm: function addAlarm(aAlarm, aResultCb) {
     this.dbNewTxn(ALARMS_STORE_NAME, "readwrite", function(txn, store) {
       if (DEBUG) {
         debug("Going to add " + JSON.stringify(aAlarm));
       }
       let record = this.alarmToRecord(aAlarm);
       store.put(record).onsuccess = function setResult(aEvent) {
         txn.result = aEvent.target.result;
         if (DEBUG) {
           debug("Request successful. New record ID: " + txn.result);
         }
       };
     }.bind(this), aResultCb);
   },
   getFirstAlarm: function getFirstAlarm(aNetworkId, aResultCb) {
     let self = this;
     this.dbNewTxn(ALARMS_STORE_NAME, "readonly", function(txn, store) {
       if (DEBUG) {
         debug("Get first alarm for network " + aNetworkId);
       }
       let lowerFilter = [aNetworkId, 0];
       let upperFilter = [aNetworkId, ""];
       let range = IDBKeyRange.bound(lowerFilter, upperFilter);
       store.index("alarm").openCursor(range).onsuccess = function onsuccess(event) {
         let cursor = event.target.result;
         txn.result = null;
         if (cursor) {
           txn.result = self.recordToAlarm(cursor.value);
         }
       };
     }, aResultCb);
   },
   removeAlarm: function removeAlarm(aAlarmId, aManifestURL, aResultCb) {
     this.dbNewTxn(ALARMS_STORE_NAME, "readwrite", function(txn, store) {
       if (DEBUG) {
         debug("Remove alarm " + aAlarmId);
       }
       store.get(aAlarmId).onsuccess = function onsuccess(event) {
         let record = event.target.result;
         txn.result = false;
         if (!record || (aManifestURL && record.manifestURL != aManifestURL)) {
           return;
         }
         store.delete(aAlarmId);
         txn.result = true;
       }
     }, aResultCb);
   },
   removeAlarms: function removeAlarms(aManifestURL, aResultCb) {
     this.dbNewTxn(ALARMS_STORE_NAME, "readwrite", function(txn, store) {
       if (DEBUG) {
         debug("Remove alarms of " + aManifestURL);
       }
       store.index("manifestURL").openCursor(aManifestURL)
                                 .onsuccess = function onsuccess(event) {
         let cursor = event.target.result;
         if (cursor) {
           cursor.delete();
           cursor.continue();
         }
       }
     }, aResultCb);
   },
   updateAlarm: function updateAlarm(aAlarm, aResultCb) {
     let self = this;
     this.dbNewTxn(ALARMS_STORE_NAME, "readwrite", function(txn, store) {
       if (DEBUG) {
         debug("Update alarm " + aAlarm.id);
       }
       let record = self.alarmToRecord(aAlarm);
       store.openCursor(record.id).onsuccess = function onsuccess(event) {
         let cursor = event.target.result;
         txn.result = false;
         if (cursor) {
           cursor.update(record);
           txn.result = true;
         }
       }
     }, aResultCb);
   },
   getAlarms: function getAlarms(aNetworkId, aManifestURL, aResultCb) {
     let self = this;
     this.dbNewTxn(ALARMS_STORE_NAME, "readonly", function(txn, store) {
       if (DEBUG) {
         debug("Get alarms for " + aManifestURL);
       }
       txn.result = [];
       store.index("manifestURL").openCursor(aManifestURL)
                                 .onsuccess = function onsuccess(event) {
         let cursor = event.target.result;
         if (!cursor) {
           return;
         }
         if (!aNetworkId || cursor.value.networkId == aNetworkId) {
           txn.result.push(self.recordToAlarm(cursor.value));
         }
         cursor.continue();
       }
     }, aResultCb);
   },
   _resetAlarms: function _resetAlarms(aNetworkId, aResultCb) {
     this.dbNewTxn(ALARMS_STORE_NAME, "readwrite", function(txn, store) {
       if (DEBUG) {
         debug("Reset alarms for network " + aNetworkId);
       }
       let lowerFilter = [aNetworkId, 0];
       let upperFilter = [aNetworkId, ""];
       let range = IDBKeyRange.bound(lowerFilter, upperFilter);
       store.index("alarm").openCursor(range).onsuccess = function onsuccess(event) {
         let cursor = event.target.result;
         if (cursor) {
           if (cursor.value.startTime) {
             cursor.value.relativeThreshold = cursor.value.threshold;
             cursor.update(cursor.value);
           }
           cursor.continue();
           return;
         }
       };
     }, aResultCb);
   }
 };

The Tor Browser / annotate

dom/network/src/NetworkStatsDB.jsm@b8a032363ba2 (annotated)

dom/network/src/NetworkStatsDB.jsm