Use new timeline cache structure

src/Cache.cpp

@@ -37,7 +37,7 @@
 
 //! Should be changed when a breaking change occurs in the cache format.
 //! This will reset client's data.
-static const std::string CURRENT_CACHE_FORMAT_VERSION("2020.05.01");
+static const std::string CURRENT_CACHE_FORMAT_VERSION("2020.07.05");
 static const std::string SECRET("secret");
 
 static lmdb::val NEXT_BATCH_KEY("next_batch");
@@ -48,6 +48,7 @@ constexpr size_t MAX_RESTORED_MESSAGES = 30'000;
 
 constexpr auto DB_SIZE    = 32ULL * 1024ULL * 1024ULL * 1024ULL; // 32 GB
 constexpr auto MAX_DBS    = 8092UL;
+constexpr auto BATCH_SIZE = 100;
 
 //! Cache databases and their format.
 //!
@@ -63,7 +64,6 @@ constexpr auto SYNC_STATE_DB("sync_state");
 //! Read receipts per room/event.
 constexpr auto READ_RECEIPTS_DB("read_receipts");
 constexpr auto NOTIFICATIONS_DB("sent_notifications");
-//! TODO: delete pending_receipts database on old cache versions
 
 //! Encryption related databases.
 
@@ -93,20 +93,6 @@ namespace {
 std::unique_ptr<Cache> instance_ = nullptr;
 }
 
-int
-numeric_key_comparison(const MDB_val *a, const MDB_val *b)
-{
-        auto lhs = std::stoull(std::string((char *)a->mv_data, a->mv_size));
-        auto rhs = std::stoull(std::string((char *)b->mv_data, b->mv_size));
-
-        if (lhs < rhs)
-                return 1;
-        else if (lhs == rhs)
-                return 0;
-
-        return -1;
-}
-
 Cache::Cache(const QString &userId, QObject *parent)
   : QObject{parent}
   , env_{nullptr}
@@ -697,6 +683,27 @@ Cache::runMigrations()
                            return false;
                    }
 
+                   nhlog::db()->info("Successfully deleted pending receipts database.");
+                   return true;
+           }},
+          {"2020.07.05",
+           [this]() {
+                   try {
+                           auto txn      = lmdb::txn::begin(env_, nullptr);
+                           auto room_ids = getRoomIds(txn);
+
+                           for (const auto &room_id : room_ids) {
+                                   auto messagesDb = lmdb::dbi::open(
+                                     txn, std::string(room_id + "/messages").c_str(), MDB_CREATE);
+                                   lmdb::dbi_drop(txn, messagesDb, true);
+                           }
+                           txn.commit();
+                   } catch (const lmdb::error &) {
+                           nhlog::db()->critical(
+                             "Failed to delete messages database in migration!");
+                           return false;
+                   }
+
                    nhlog::db()->info("Successfully deleted pending receipts database.");
                    return true;
            }},
@@ -1232,38 +1239,64 @@ Cache::getTimelineMentions()
         return notifs;
 }
 
-mtx::responses::Timeline
+Cache::Messages
-Cache::getTimelineMessages(lmdb::txn &txn, const std::string &room_id)
+Cache::getTimelineMessages(lmdb::txn &txn, const std::string &room_id, int64_t index, bool forward)
 {
         // TODO(nico): Limit the messages returned by this maybe?
-        auto db = getMessagesDb(txn, room_id);
+        auto orderDb  = getEventOrderDb(txn, room_id);
+        auto eventsDb = getEventsDb(txn, room_id);
 
-        mtx::responses::Timeline timeline;
+        Messages messages{};
-        std::string timestamp, msg;
 
-        auto cursor = lmdb::cursor::open(txn, db);
+        lmdb::val indexVal, val;
 
-        size_t index = 0;
+        auto cursor = lmdb::cursor::open(txn, orderDb);
+        if (index == std::numeric_limits<int64_t>::max()) {
+                if (cursor.get(indexVal, val, forward ? MDB_FIRST : MDB_LAST)) {
+                        index = *indexVal.data<int64_t>();
+                } else {
+                        messages.end_of_cache = true;
+                        return messages;
+                }
+        } else {
+                if (cursor.get(indexVal, val, MDB_SET)) {
+                        index = *indexVal.data<int64_t>();
+                } else {
+                        messages.end_of_cache = true;
+                        return messages;
+                }
+        }
 
-        while (cursor.get(timestamp, msg, MDB_NEXT) && index < MAX_RESTORED_MESSAGES) {
+        int counter = 0;
-                auto obj = json::parse(msg);
 
-                if (obj.count("event") == 0 || obj.count("token") == 0)
+        bool ret;
+        while ((ret = cursor.get(indexVal, val, forward ? MDB_NEXT : MDB_LAST)) &&
+               counter++ < BATCH_SIZE) {
+                auto obj = json::parse(std::string(val.data(), val.size()));
+
+                if (obj.count("event_id") == 0)
+                        break;
+
+                lmdb::val event;
+                bool success = lmdb::dbi_get(
+                  txn, eventsDb, lmdb::val(obj["event_id"].get<std::string>()), event);
+                if (!success)
                         continue;
 
-                mtx::events::collections::TimelineEvent event;
+                mtx::events::collections::TimelineEvent te;
-                mtx::events::collections::from_json(obj.at("event"), event);
+                mtx::events::collections::from_json(
+                  json::parse(std::string(event.data(), event.size())), te);
 
-                index += 1;
+                messages.timeline.events.push_back(std::move(te.data));
-
+                // timeline.prev_batch = obj.at("token").get<std::string>();
-                timeline.events.push_back(event.data);
-                timeline.prev_batch = obj.at("token").get<std::string>();
         }
         cursor.close();
 
-        std::reverse(timeline.events.begin(), timeline.events.end());
+        // std::reverse(timeline.events.begin(), timeline.events.end());
+        messages.next_index   = *indexVal.data<int64_t>();
+        messages.end_of_cache = !ret;
 
-        return timeline;
+        return messages;
 }
 
 QMap<QString, RoomInfo>
@@ -1306,55 +1339,59 @@ Cache::roomInfo(bool withInvites)
 std::string
 Cache::getLastEventId(lmdb::txn &txn, const std::string &room_id)
 {
-        auto db = getMessagesDb(txn, room_id);
+        auto orderDb = getEventOrderDb(txn, room_id);
 
-        if (db.size(txn) == 0)
+        lmdb::val indexVal, val;
+
+        auto cursor = lmdb::cursor::open(txn, orderDb);
+        if (!cursor.get(indexVal, val, MDB_LAST)) {
                 return {};
-
-        std::string timestamp, msg;
-
-        auto cursor = lmdb::cursor::open(txn, db);
-        while (cursor.get(timestamp, msg, MDB_NEXT)) {
-                auto obj = json::parse(msg);
-
-                if (obj.count("event") == 0)
-                        continue;
-
-                cursor.close();
-                return obj["event"]["event_id"];
         }
-        cursor.close();
 
+        auto obj = json::parse(std::string(val.data(), val.size()));
+
+        if (obj.count("event_id") == 0)
                 return {};
+        else
+                return obj["event_id"];
 }
 
 DescInfo
 Cache::getLastMessageInfo(lmdb::txn &txn, const std::string &room_id)
 {
-        auto db = getMessagesDb(txn, room_id);
+        auto orderDb  = getEventOrderDb(txn, room_id);
-
+        auto eventsDb = getEventsDb(txn, room_id);
-        if (db.size(txn) == 0)
+        if (orderDb.size(txn) == 0)
                 return DescInfo{};
 
-        std::string timestamp, msg;
-
         const auto local_user = utils::localUser();
 
         DescInfo fallbackDesc{};
 
-        auto cursor = lmdb::cursor::open(txn, db);
+        lmdb::val indexVal, val;
-        while (cursor.get(timestamp, msg, MDB_NEXT)) {
-                auto obj = json::parse(msg);
 
-                if (obj.count("event") == 0)
+        auto cursor = lmdb::cursor::open(txn, orderDb);
+        cursor.get(indexVal, val, MDB_LAST);
+        while (cursor.get(indexVal, val, MDB_PREV)) {
+                auto temp = json::parse(std::string(val.data(), val.size()));
+
+                if (temp.count("event_id") == 0)
+                        break;
+
+                lmdb::val event;
+                bool success = lmdb::dbi_get(
+                  txn, eventsDb, lmdb::val(temp["event_id"].get<std::string>()), event);
+                if (!success)
                         continue;
 
-                if (fallbackDesc.event_id.isEmpty() && obj["event"]["type"] == "m.room.member" &&
+                auto obj = json::parse(std::string(event.data(), event.size()));
-                    obj["event"]["state_key"] == local_user.toStdString() &&
+
-                    obj["event"]["content"]["membership"] == "join") {
+                if (fallbackDesc.event_id.isEmpty() && obj["type"] == "m.room.member" &&
-                        uint64_t ts  = obj["event"]["origin_server_ts"];
+                    obj["state_key"] == local_user.toStdString() &&
+                    obj["content"]["membership"] == "join") {
+                        uint64_t ts  = obj["origin_server_ts"];
                         auto time    = QDateTime::fromMSecsSinceEpoch(ts);
-                        fallbackDesc = DescInfo{QString::fromStdString(obj["event"]["event_id"]),
+                        fallbackDesc = DescInfo{QString::fromStdString(obj["event_id"]),
                                                 local_user,
                                                 tr("You joined this room."),
                                                 utils::descriptiveTime(time),
@@ -1362,17 +1399,16 @@ Cache::getLastMessageInfo(lmdb::txn &txn, const std::string &room_id)
                                                 time};
                 }
 
-                if (!(obj["event"]["type"] == "m.room.message" ||
+                if (!(obj["type"] == "m.room.message" || obj["type"] == "m.sticker" ||
-                      obj["event"]["type"] == "m.sticker" ||
+                      obj["type"] == "m.room.encrypted"))
-                      obj["event"]["type"] == "m.room.encrypted"))
                         continue;
 
-                mtx::events::collections::TimelineEvent event;
+                mtx::events::collections::TimelineEvent te;
-                mtx::events::collections::from_json(obj.at("event"), event);
+                mtx::events::collections::from_json(obj, te);
 
                 cursor.close();
                 return utils::getMessageDescription(
-                  event.data, local_user, QString::fromStdString(room_id));
+                  te.data, local_user, QString::fromStdString(room_id));
         }
         cursor.close();
 
@@ -1954,7 +1990,6 @@ Cache::saveTimelineMessages(lmdb::txn &txn,
                             const std::string &room_id,
                             const mtx::responses::Timeline &res)
 {
-        auto db = getMessagesDb(txn, room_id);
         auto eventsDb = getEventsDb(txn, room_id);
 
         auto orderDb = getEventOrderDb(txn, room_id);
@@ -1979,17 +2014,6 @@ Cache::saveTimelineMessages(lmdb::txn &txn,
                         lmdb::dbi_put(
                           txn, eventsDb, lmdb::val(redaction->redacts), lmdb::val(event.dump()));
                 } else {
-                        json obj = json::object();
-
-                        obj["event"] = event;
-                        obj["token"] = res.prev_batch;
-
-                        lmdb::dbi_put(
-                          txn,
-                          db,
-                          lmdb::val(std::to_string(event["origin_server_ts"].get<uint64_t>())),
-                          lmdb::val(obj.dump()));
-
                         lmdb::dbi_put(txn,
                                       eventsDb,
                                       lmdb::val(event["event_id"].get<std::string>()),
@@ -1997,9 +2021,16 @@ Cache::saveTimelineMessages(lmdb::txn &txn,
 
                         ++index;
 
+                        json orderEntry        = json::object();
+                        orderEntry["event_id"] = event["event_id"];
+                        if (first)
+                                orderEntry["prev_batch"] = res.prev_batch;
+
+                        nhlog::db()->debug("saving '{}'", orderEntry.dump());
+
                         lmdb::cursor_put(cursor.handle(),
                                          lmdb::val(&index, sizeof(index)),
-                                         lmdb::val(first ? res.prev_batch : ""),
+                                         lmdb::val(orderEntry.dump()),
                                          MDB_APPEND);
                         first = false;
                 }
@@ -2138,34 +2169,43 @@ Cache::getRoomIds(lmdb::txn &txn)
 void
 Cache::deleteOldMessages()
 {
+        lmdb::val indexVal, val;
+
         auto txn      = lmdb::txn::begin(env_);
         auto room_ids = getRoomIds(txn);
 
-        for (const auto &id : room_ids) {
+        for (const auto &room_id : room_ids) {
-                auto msg_db = getMessagesDb(txn, id);
+                auto orderDb  = getEventOrderDb(txn, room_id);
+                auto eventsDb = getEventsDb(txn, room_id);
+                auto cursor   = lmdb::cursor::open(txn, orderDb);
 
-                std::string ts, event;
+                int64_t first, last;
-                uint64_t idx = 0;
+                if (cursor.get(indexVal, val, MDB_LAST)) {
+                        last = *indexVal.data<int64_t>();
+                } else {
+                        continue;
+                }
+                if (cursor.get(indexVal, val, MDB_FIRST)) {
+                        first = *indexVal.data<int64_t>();
+                } else {
+                        continue;
+                }
 
-                const auto db_size = msg_db.size(txn);
+                size_t message_count = static_cast<size_t>(last - first);
-                if (db_size <= 3 * MAX_RESTORED_MESSAGES)
+                if (message_count < MAX_RESTORED_MESSAGES)
                         continue;
 
-                nhlog::db()->info("[{}] message count: {}", id, db_size);
+                while (cursor.get(indexVal, val, MDB_NEXT) &&
+                       message_count-- < MAX_RESTORED_MESSAGES) {
+                        auto obj = json::parse(std::string(val.data(), val.size()));
 
-                auto cursor = lmdb::cursor::open(txn, msg_db);
+                        if (obj.count("event_id") != 0)
-                while (cursor.get(ts, event, MDB_NEXT)) {
+                                lmdb::dbi_del(
-                        idx += 1;
+                                  txn, eventsDb, lmdb::val(obj["event_id"].get<std::string>()));
-
-                        if (idx > MAX_RESTORED_MESSAGES)
                         lmdb::cursor_del(cursor);
                 }
-
                 cursor.close();
-
-                nhlog::db()->info("[{}] updated message count: {}", id, msg_db.size(txn));
         }
-
         txn.commit();
 }
 

src/Cache_p.h

@@ -18,6 +18,7 @@
 
 #pragma once
 
+#include <limits>
 #include <optional>
 
 #include <QDateTime>
@@ -38,9 +39,6 @@
 #include "CacheCryptoStructs.h"
 #include "CacheStructs.h"
 
-int
-numeric_key_comparison(const MDB_val *a, const MDB_val *b);
-
 class Cache : public QObject
 {
         Q_OBJECT
@@ -250,7 +248,16 @@ private:
                                   const std::string &room_id,
                                   const mtx::responses::Timeline &res);
 
-        mtx::responses::Timeline getTimelineMessages(lmdb::txn &txn, const std::string &room_id);
+        struct Messages
+        {
+                mtx::responses::Timeline timeline;
+                uint64_t next_index;
+                bool end_of_cache = false;
+        };
+        Messages getTimelineMessages(lmdb::txn &txn,
+                                     const std::string &room_id,
+                                     int64_t index = std::numeric_limits<int64_t>::max(),
+                                     bool forward  = false);
 
         //! Remove a room from the cache.
         // void removeLeftRoom(lmdb::txn &txn, const std::string &room_id);
@@ -402,15 +409,6 @@ private:
                 return lmdb::dbi::open(txn, "pending_receipts", MDB_CREATE);
         }
 
-        lmdb::dbi getMessagesDb(lmdb::txn &txn, const std::string &room_id)
-        {
-                auto db =
-                  lmdb::dbi::open(txn, std::string(room_id + "/messages").c_str(), MDB_CREATE);
-                lmdb::dbi_set_compare(txn, db, numeric_key_comparison);
-
-                return db;
-        }
-
         lmdb::dbi getEventsDb(lmdb::txn &txn, const std::string &room_id)
         {
                 return lmdb::dbi::open(txn, std::string(room_id + "/events").c_str(), MDB_CREATE);