src/core/abstractsqlstorage.cpp

   1 /***************************************************************************
   2  *   Copyright (C) 2005-2019 by the Quassel Project                        *
   3  *   devel@quassel-irc.org                                                 *
   4  *                                                                         *
   5  *   This program is free software; you can redistribute it and/or modify  *
   6  *   it under the terms of the GNU General Public License as published by  *
   7  *   the Free Software Foundation; either version 2 of the License, or     *
   8  *   (at your option) version 3.                                           *
   9  *                                                                         *
  10  *   This program is distributed in the hope that it will be useful,       *
  11  *   but WITHOUT ANY WARRANTY; without even the implied warranty of        *
  12  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         *
  13  *   GNU General Public License for more details.                          *
  14  *                                                                         *
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  18  *   51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.         *
  19  ***************************************************************************/
  20
  21 #include "abstractsqlstorage.h"
  22
  23 #include <QMutexLocker>
  24 #include <QSqlDriver>
  25 #include <QSqlError>
  26 #include <QSqlField>
  27 #include <QSqlQuery>
  28
  29 #include "logmessage.h"
  30 #include "quassel.h"
  31
  32 int AbstractSqlStorage::_nextConnectionId = 0;
  33 AbstractSqlStorage::AbstractSqlStorage(QObject *parent)
  34     : Storage(parent),
  35     _schemaVersion(0)
  36 {
  37 }
  38
  39
  40 AbstractSqlStorage::~AbstractSqlStorage()
  41 {
  42     // disconnect the connections, so their deletion is no longer interessting for us
  43     QHash<QThread *, Connection *>::iterator conIter;
  44     for (conIter = _connectionPool.begin(); conIter != _connectionPool.end(); ++conIter) {
  45         QSqlDatabase::removeDatabase(conIter.value()->name());
  46         disconnect(conIter.value(), 0, this, 0);
  47     }
  48 }
  49
  50
  51 QSqlDatabase AbstractSqlStorage::logDb()
  52 {
  53     if (!_connectionPool.contains(QThread::currentThread()))
  54         addConnectionToPool();
  55
  56     QSqlDatabase db = QSqlDatabase::database(_connectionPool[QThread::currentThread()]->name(),false);
  57
  58     if (!db.isOpen()) {
  59         qWarning() << "Database connection" << displayName() << "for thread" << QThread::currentThread() << "was lost, attempting to reconnect...";
  60         dbConnect(db);
  61     }
  62
  63     return db;
  64 }
  65
  66
  67 void AbstractSqlStorage::addConnectionToPool()
  68 {
  69     QMutexLocker locker(&_connectionPoolMutex);
  70     // we have to recheck if the connection pool already contains a connection for
  71     // this thread. Since now (after the lock) we can only tell for sure
  72     if (_connectionPool.contains(QThread::currentThread()))
  73         return;
  74
  75     QThread *currentThread = QThread::currentThread();
  76
  77     int connectionId = _nextConnectionId++;
  78
  79     Connection *connection = new Connection(QLatin1String(QString("quassel_%1_con_%2").arg(driverName()).arg(connectionId).toLatin1()));
  80     connection->moveToThread(currentThread);
  81     connect(this, SIGNAL(destroyed()), connection, SLOT(deleteLater()));
  82     connect(currentThread, SIGNAL(destroyed()), connection, SLOT(deleteLater()));
  83     connect(connection, SIGNAL(destroyed()), this, SLOT(connectionDestroyed()));
  84     _connectionPool[currentThread] = connection;
  85
  86     QSqlDatabase db = QSqlDatabase::addDatabase(driverName(), connection->name());
  87     db.setDatabaseName(databaseName());
  88
  89     if (!hostName().isEmpty())
  90         db.setHostName(hostName());
  91
  92     if (port() != -1)
  93         db.setPort(port());
  94
  95     if (!userName().isEmpty()) {
  96         db.setUserName(userName());
  97         db.setPassword(password());
  98     }
  99
 100     dbConnect(db);
 101 }
 102
 103
 104 void AbstractSqlStorage::dbConnect(QSqlDatabase &db)
 105 {
 106     if (!db.open()) {
 107         quWarning() << "Unable to open database" << displayName() << "for thread" << QThread::currentThread();
 108         quWarning() << "-" << db.lastError().text();
 109     }
 110     else {
 111         if (!initDbSession(db)) {
 112             quWarning() << "Unable to initialize database" << displayName() << "for thread" << QThread::currentThread();
 113             db.close();
 114         }
 115     }
 116 }
 117
 118
 119 Storage::State AbstractSqlStorage::init(const QVariantMap &settings,
 120                                         const QProcessEnvironment &environment,
 121                                         bool loadFromEnvironment)
 122 {
 123     setConnectionProperties(settings, environment, loadFromEnvironment);
 124
 125     _debug = Quassel::isOptionSet("debug");
 126
 127     QSqlDatabase db = logDb();
 128     if (!db.isValid() || !db.isOpen())
 129         return NotAvailable;
 130
 131     if (installedSchemaVersion() == -1) {
 132         qCritical() << "Storage Schema is missing!";
 133         return NeedsSetup;
 134     }
 135
 136     if (installedSchemaVersion() > schemaVersion()) {
 137         qCritical() << "Installed Schema is newer then any known Version.";
 138         return NotAvailable;
 139     }
 140
 141     if (installedSchemaVersion() < schemaVersion()) {
 142         quInfo() << qPrintable(tr("Installed database schema (version %1) is not up to date. Upgrading to "
 143                                   "version %2...  This may take a while for major upgrades."
 144                                  ).arg(installedSchemaVersion()).arg(schemaVersion()));
 145         emit dbUpgradeInProgress(true);
 146         auto upgradeResult = upgradeDb();
 147         emit dbUpgradeInProgress(false);
 148         if (!upgradeResult) {
 149             qWarning() << qPrintable(tr("Upgrade failed..."));
 150             return NotAvailable;
 151         }
 152         // Add a message when migration succeeds to avoid confusing folks by implying the schema upgrade failed if
 153         // later functionality does not work.
 154         quInfo() << qPrintable(tr("Installed database schema successfully upgraded to version %1.").arg(schemaVersion()));
 155     }
 156
 157     quInfo() << qPrintable(displayName()) << "storage backend is ready. Schema version:" << installedSchemaVersion();
 158     return IsReady;
 159 }
 160
 161
 162 QString AbstractSqlStorage::queryString(const QString &queryName, int version)
 163 {
 164     QFileInfo queryInfo;
 165
 166     // The current schema is stored in the root folder, while upgrade queries are stored in the
 167     // 'versions/##' subfolders.
 168     if (version == 0) {
 169         // Use the current SQL schema, not a versioned request
 170         queryInfo = QFileInfo(QString(":/SQL/%1/%2.sql").arg(displayName()).arg(queryName));
 171         // If version is needed later, get it via version = schemaVersion();
 172     } else {
 173         // Use the specified schema version, not the general folder
 174         queryInfo = QFileInfo(QString(":/SQL/%1/version/%2/%3.sql")
 175                               .arg(displayName()).arg(version).arg(queryName));
 176     }
 177
 178     if (!queryInfo.exists() || !queryInfo.isFile() || !queryInfo.isReadable()) {
 179         qCritical() << "Unable to read SQL-Query" << queryName << "for engine" << displayName();
 180         return QString();
 181     }
 182
 183     QFile queryFile(queryInfo.filePath());
 184     if (!queryFile.open(QIODevice::ReadOnly | QIODevice::Text))
 185         return QString();
 186     QString query = QTextStream(&queryFile).readAll();
 187     queryFile.close();
 188
 189     return query.trimmed();
 190 }
 191
 192
 193 QList<AbstractSqlStorage::SqlQueryResource> AbstractSqlStorage::setupQueries()
 194 {
 195     QList<SqlQueryResource> queries;
 196     // The current schema is stored in the root folder, including setup scripts.
 197     QDir dir = QDir(QString(":/SQL/%1/").arg(displayName()));
 198     foreach(QFileInfo fileInfo, dir.entryInfoList(QStringList() << "setup*", QDir::NoFilter, QDir::Name)) {
 199         queries << SqlQueryResource(queryString(fileInfo.baseName()), fileInfo.baseName());
 200     }
 201     return queries;
 202 }
 203
 204
 205 bool AbstractSqlStorage::setup(const QVariantMap &settings, const QProcessEnvironment &environment,
 206                                bool loadFromEnvironment)
 207 {
 208     setConnectionProperties(settings, environment, loadFromEnvironment);
 209     QSqlDatabase db = logDb();
 210     if (!db.isOpen()) {
 211         qCritical() << "Unable to setup Logging Backend!";
 212         return false;
 213     }
 214
 215     db.transaction();
 216     foreach (auto queryResource, setupQueries()) {
 217         QSqlQuery query = db.exec(queryResource.queryString);
 218         if (!watchQuery(query)) {
 219             qCritical() << qPrintable(QString("Unable to setup Logging Backend!  Setup query failed (step: %1).")
 220                                       .arg(queryResource.queryFilename));
 221             db.rollback();
 222             return false;
 223         }
 224     }
 225     bool success = setupSchemaVersion(schemaVersion());
 226     if (success)
 227         db.commit();
 228     else
 229         db.rollback();
 230     return success;
 231 }
 232
 233
 234 QList<AbstractSqlStorage::SqlQueryResource> AbstractSqlStorage::upgradeQueries(int version)
 235 {
 236     QList<SqlQueryResource> queries;
 237     // Upgrade queries are stored in the 'version/##' subfolders.
 238     QDir dir = QDir(QString(":/SQL/%1/version/%2/").arg(displayName()).arg(version));
 239     foreach(QFileInfo fileInfo, dir.entryInfoList(QStringList() << "upgrade*", QDir::NoFilter, QDir::Name)) {
 240         queries << SqlQueryResource(queryString(fileInfo.baseName(), version), fileInfo.baseName());
 241     }
 242     return queries;
 243 }
 244
 245
 246 bool AbstractSqlStorage::upgradeDb()
 247 {
 248     if (schemaVersion() <= installedSchemaVersion())
 249         return true;
 250
 251     QSqlDatabase db = logDb();
 252
 253     // TODO: For databases that support it (e.g. almost only PostgreSQL), wrap upgrades in a
 254     // transaction.  This will need careful testing of potential additional space requirements and
 255     // any database modifications that might not be allowed in a transaction.
 256
 257     // Check if we're resuming an interrupted multi-step upgrade: is an upgrade step stored?
 258     const QString previousLaunchUpgradeStep = schemaVersionUpgradeStep();
 259     bool resumingUpgrade = !previousLaunchUpgradeStep.isEmpty();
 260
 261     for (int ver = installedSchemaVersion() + 1; ver <= schemaVersion(); ver++) {
 262         foreach (auto queryResource, upgradeQueries(ver)) {
 263             if (resumingUpgrade) {
 264                 // An upgrade was interrupted.  Check if this matches the the last successful query.
 265                 if (previousLaunchUpgradeStep == queryResource.queryFilename) {
 266                     // Found the matching query!
 267                     quInfo() << qPrintable(QString("Resuming interrupted upgrade for schema version %1 (last step: %2)")
 268                                            .arg(QString::number(ver), previousLaunchUpgradeStep));
 269
 270                     // Stop searching for queries
 271                     resumingUpgrade = false;
 272                     // Continue past the previous query with the next not-yet-tried query
 273                     continue;
 274                 }
 275                 else {
 276                     // Not yet matched, keep looking
 277                     continue;
 278                 }
 279             }
 280
 281             // Run the upgrade query
 282             QSqlQuery query = db.exec(queryResource.queryString);
 283             if (!watchQuery(query)) {
 284                 // Individual upgrade query failed, bail out
 285                 qCritical() << qPrintable(QString("Unable to upgrade Logging Backend!  Upgrade query in schema version %1 failed (step: %2).")
 286                                           .arg(QString::number(ver), queryResource.queryFilename));
 287                 return false;
 288             }
 289             else {
 290                 // Mark as successful
 291                 setSchemaVersionUpgradeStep(queryResource.queryFilename);
 292             }
 293         }
 294
 295         if (resumingUpgrade) {
 296             // Something went wrong and the last successful SQL query to resume from couldn't be
 297             // found.
 298             // 1.  The storage of successful query glitched, or the database was manually changed
 299             // 2.  Quassel changed the filenames of upgrade queries, and the local Quassel core
 300             //     version was replaced during an interrupted schema upgrade
 301             //
 302             // Both are unlikely, but it's a good idea to handle it anyways.
 303
 304             qCritical() << qPrintable(QString("Unable to resume interrupted upgrade in Logging "
 305                                               "Backend!  Missing upgrade step in schema version %1 "
 306                                               "(expected step: %2)")
 307                                       .arg(QString::number(ver), previousLaunchUpgradeStep));
 308             return false;
 309         }
 310
 311         // Update the schema version for each intermediate step and mark the step as done.  This
 312         // ensures that any interrupted upgrades have a greater chance of resuming correctly after
 313         // core restart.
 314         //
 315         // Almost all databases make single queries atomic (fully works or fully fails, no partial),
 316         // and with many of the longest migrations being a single query, this makes upgrade
 317         // interruptions much more likely to leave the database in a valid intermediate schema
 318         // version.
 319         if (!updateSchemaVersion(ver, true)) {
 320             // Updating the schema version failed, bail out
 321             qCritical() << "Unable to upgrade Logging Backend!  Setting schema version"
 322                         << ver << "failed.";
 323             return false;
 324         }
 325     }
 326
 327     // If we made it here, everything seems to have worked!
 328     return true;
 329 }
 330
 331
 332 int AbstractSqlStorage::schemaVersion()
 333 {
 334     // returns the newest Schema Version!
 335     // not the currently used one! (though it can be the same)
 336     if (_schemaVersion > 0)
 337         return _schemaVersion;
 338
 339     int version;
 340     bool ok;
 341     // Schema versions are stored in the 'version/##' subfolders.
 342     QDir dir = QDir(QString(":/SQL/%1/version/").arg(displayName()));
 343     foreach(QFileInfo fileInfo, dir.entryInfoList()) {
 344         if (!fileInfo.isDir())
 345             continue;
 346
 347         version = fileInfo.fileName().toInt(&ok);
 348         if (!ok)
 349             continue;
 350
 351         if (version > _schemaVersion)
 352             _schemaVersion = version;
 353     }
 354     return _schemaVersion;
 355 }
 356
 357
 358 QString AbstractSqlStorage::schemaVersionUpgradeStep()
 359 {
 360     // By default, assume there's no pending upgrade
 361     return {};
 362 }
 363
 364
 365 bool AbstractSqlStorage::watchQuery(QSqlQuery &query)
 366 {
 367     bool queryError = query.lastError().isValid();
 368     if (queryError || _debug) {
 369         if (queryError)
 370             qCritical() << "unhandled Error in QSqlQuery!";
 371         qCritical() << "                  last Query:\n" << qPrintable(query.lastQuery());
 372         qCritical() << "              executed Query:\n" << qPrintable(query.executedQuery());
 373         QVariantMap boundValues = query.boundValues();
 374         QStringList valueStrings;
 375         QVariantMap::const_iterator iter;
 376         for (iter = boundValues.constBegin(); iter != boundValues.constEnd(); ++iter) {
 377             QString value;
 378             QSqlField field;
 379             if (query.driver()) {
 380                 // let the driver do the formatting
 381                 field.setType(iter.value().type());
 382                 if (iter.value().isNull())
 383                     field.clear();
 384                 else
 385                     field.setValue(iter.value());
 386                 value =  query.driver()->formatValue(field);
 387             }
 388             else {
 389                 switch (iter.value().type()) {
 390                 case QVariant::Invalid:
 391                     value = "NULL";
 392                     break;
 393                 case QVariant::Int:
 394                     value = iter.value().toString();
 395                     break;
 396                 default:
 397                     value = QString("'%1'").arg(iter.value().toString());
 398                 }
 399             }
 400             valueStrings << QString("%1=%2").arg(iter.key(), value);
 401         }
 402         qCritical() << "                bound Values:" << qPrintable(valueStrings.join(", "));
 403         qCritical() << "                Error Number:" << query.lastError().number();
 404         qCritical() << "               Error Message:" << qPrintable(query.lastError().text());
 405         qCritical() << "              Driver Message:" << qPrintable(query.lastError().driverText());
 406         qCritical() << "                  DB Message:" << qPrintable(query.lastError().databaseText());
 407
 408         return !queryError;
 409     }
 410     return true;
 411 }
 412
 413
 414 void AbstractSqlStorage::connectionDestroyed()
 415 {
 416     QMutexLocker locker(&_connectionPoolMutex);
 417     _connectionPool.remove(sender()->thread());
 418 }
 419
 420
 421 // ========================================
 422 //  AbstractSqlStorage::Connection
 423 // ========================================
 424 AbstractSqlStorage::Connection::Connection(const QString &name, QObject *parent)
 425     : QObject(parent),
 426     _name(name.toLatin1())
 427 {
 428 }
 429
 430
 431 AbstractSqlStorage::Connection::~Connection()
 432 {
 433     {
 434         QSqlDatabase db = QSqlDatabase::database(name(), false);
 435         if (db.isOpen()) {
 436             db.commit();
 437             db.close();
 438         }
 439     }
 440     QSqlDatabase::removeDatabase(name());
 441 }
 442
 443
 444 // ========================================
 445 //  AbstractSqlMigrator
 446 // ========================================
 447 AbstractSqlMigrator::AbstractSqlMigrator()
 448     : _query(0)
 449 {
 450 }
 451
 452
 453 void AbstractSqlMigrator::newQuery(const QString &query, QSqlDatabase db)
 454 {
 455     Q_ASSERT(!_query);
 456     _query = new QSqlQuery(db);
 457     _query->prepare(query);
 458 }
 459
 460
 461 void AbstractSqlMigrator::resetQuery()
 462 {
 463     delete _query;
 464     _query = 0;
 465 }
 466
 467
 468 bool AbstractSqlMigrator::exec()
 469 {
 470     Q_ASSERT(_query);
 471     _query->exec();
 472     return !_query->lastError().isValid();
 473 }
 474
 475
 476 QString AbstractSqlMigrator::migrationObject(MigrationObject moType)
 477 {
 478     switch (moType) {
 479     case QuasselUser:
 480         return "QuasselUser";
 481     case Sender:
 482         return "Sender";
 483     case Identity:
 484         return "Identity";
 485     case IdentityNick:
 486         return "IdentityNick";
 487     case Network:
 488         return "Network";
 489     case Buffer:
 490         return "Buffer";
 491     case Backlog:
 492         return "Backlog";
 493     case IrcServer:
 494         return "IrcServer";
 495     case UserSetting:
 496         return "UserSetting";
 497     case CoreState:
 498         return "CoreState";
 499     };
 500     return QString();
 501 }
 502
 503
 504 QVariantList AbstractSqlMigrator::boundValues()
 505 {
 506     QVariantList values;
 507     if (!_query)
 508         return values;
 509
 510     int numValues = _query->boundValues().count();
 511     for (int i = 0; i < numValues; i++) {
 512         values << _query->boundValue(i);
 513     }
 514     return values;
 515 }
 516
 517
 518 void AbstractSqlMigrator::dumpStatus()
 519 {
 520     qWarning() << "  executed Query:";
 521     qWarning() << qPrintable(executedQuery());
 522     qWarning() << "  bound Values:";
 523     QList<QVariant> list = boundValues();
 524     for (int i = 0; i < list.size(); ++i)
 525         qWarning() << i << ": " << list.at(i).toString().toLatin1().data();
 526     qWarning() << "  Error Number:"   << lastError().number();
 527     qWarning() << "  Error Message:"   << lastError().text();
 528 }
 529
 530
 531 // ========================================
 532 //  AbstractSqlMigrationReader
 533 // ========================================
 534 AbstractSqlMigrationReader::AbstractSqlMigrationReader()
 535     : AbstractSqlMigrator(),
 536     _writer(0)
 537 {
 538 }
 539
 540
 541 bool AbstractSqlMigrationReader::migrateTo(AbstractSqlMigrationWriter *writer)
 542 {
 543     if (!transaction()) {
 544         qWarning() << "AbstractSqlMigrationReader::migrateTo(): unable to start reader's transaction!";
 545         return false;
 546     }
 547     if (!writer->transaction()) {
 548         qWarning() << "AbstractSqlMigrationReader::migrateTo(): unable to start writer's transaction!";
 549         rollback(); // close the reader transaction;
 550         return false;
 551     }
 552
 553     _writer = writer;
 554
 555     // due to the incompatibility across Migration objects we can't run this in a loop... :/
 556     QuasselUserMO quasselUserMo;
 557     if (!transferMo(QuasselUser, quasselUserMo))
 558         return false;
 559
 560     IdentityMO identityMo;
 561     if (!transferMo(Identity, identityMo))
 562         return false;
 563
 564     IdentityNickMO identityNickMo;
 565     if (!transferMo(IdentityNick, identityNickMo))
 566         return false;
 567
 568     NetworkMO networkMo;
 569     if (!transferMo(Network, networkMo))
 570         return false;
 571
 572     BufferMO bufferMo;
 573     if (!transferMo(Buffer, bufferMo))
 574         return false;
 575
 576     SenderMO senderMo;
 577     if (!transferMo(Sender, senderMo))
 578         return false;
 579
 580     BacklogMO backlogMo;
 581     if (!transferMo(Backlog, backlogMo))
 582         return false;
 583
 584     IrcServerMO ircServerMo;
 585     if (!transferMo(IrcServer, ircServerMo))
 586         return false;
 587
 588     UserSettingMO userSettingMo;
 589     if (!transferMo(UserSetting, userSettingMo))
 590         return false;
 591
 592     CoreStateMO coreStateMO;
 593     if (!transferMo(CoreState, coreStateMO))
 594         return false;
 595
 596     if (!_writer->postProcess())
 597         abortMigration();
 598     return finalizeMigration();
 599 }
 600
 601
 602 void AbstractSqlMigrationReader::abortMigration(const QString &errorMsg)
 603 {
 604     qWarning() << "Migration Failed!";
 605     if (!errorMsg.isNull()) {
 606         qWarning() << qPrintable(errorMsg);
 607     }
 608     if (lastError().isValid()) {
 609         qWarning() << "ReaderError:";
 610         dumpStatus();
 611     }
 612
 613     if (_writer->lastError().isValid()) {
 614         qWarning() << "WriterError:";
 615         _writer->dumpStatus();
 616     }
 617
 618     rollback();
 619     _writer->rollback();
 620     _writer = 0;
 621 }
 622
 623
 624 bool AbstractSqlMigrationReader::finalizeMigration()
 625 {
 626     resetQuery();
 627     _writer->resetQuery();
 628
 629     commit();
 630     if (!_writer->commit()) {
 631         _writer = 0;
 632         return false;
 633     }
 634     _writer = 0;
 635     return true;
 636 }
 637
 638
 639 template<typename T>
 640 bool AbstractSqlMigrationReader::transferMo(MigrationObject moType, T &mo)
 641 {
 642     resetQuery();
 643     _writer->resetQuery();
 644
 645     if (!prepareQuery(moType)) {
 646         abortMigration(QString("AbstractSqlMigrationReader::migrateTo(): unable to prepare reader query of type %1!").arg(AbstractSqlMigrator::migrationObject(moType)));
 647         return false;
 648     }
 649     if (!_writer->prepareQuery(moType)) {
 650         abortMigration(QString("AbstractSqlMigrationReader::migrateTo(): unable to prepare writer query of type %1!").arg(AbstractSqlMigrator::migrationObject(moType)));
 651         return false;
 652     }
 653
 654     qDebug() << qPrintable(QString("Transferring %1...").arg(AbstractSqlMigrator::migrationObject(moType)));
 655     int i = 0;
 656     QFile file;
 657     file.open(stdout, QIODevice::WriteOnly);
 658
 659     while (readMo(mo)) {
 660         if (!_writer->writeMo(mo)) {
 661             abortMigration(QString("AbstractSqlMigrationReader::transferMo(): unable to transfer Migratable Object of type %1!").arg(AbstractSqlMigrator::migrationObject(moType)));
 662             return false;
 663         }
 664         i++;
 665         if (i % 1000 == 0) {
 666             file.write("*");
 667             file.flush();
 668         }
 669     }
 670     if (i > 1000) {
 671         file.write("\n");
 672         file.flush();
 673     }
 674
 675     qDebug() << "Done.";
 676     return true;
 677 }
 678
 679 uint qHash(const SenderData &key) {
 680     return qHash(QString(key.sender + "\n" + key.realname + "\n" + key.avatarurl));
 681 }
 682
 683 bool operator==(const SenderData &a, const SenderData &b) {
 684     return a.sender == b.sender &&
 685         a.realname == b.realname &&
 686         a.avatarurl == b.avatarurl;
 687 }