Add experimental feature to reduce database writes for channel data

src/channel/channel.js

@@ -10,6 +10,7 @@ import Promise from 'bluebird';
 import { EventEmitter } from 'events';
 import { throttle } from '../util/throttle';
 import Logger from '../logger';
+import * as Switches from '../switches';
 
 const LOGGER = require('@calzoneman/jsli')('channel');
 
@@ -239,37 +240,59 @@ Channel.prototype.loadState = function () {
     });
 };
 
-Channel.prototype.saveState = function () {
+Channel.prototype.saveState = async function () {
     if (!this.is(Flags.C_REGISTERED)) {
-        return Promise.resolve();
+        return;
     } else if (!this.is(Flags.C_READY)) {
-        return Promise.reject(new Error(`Attempted to save channel ${this.name} ` +
-                `but it wasn't finished loading yet!`));
+        throw new Error(
+            `Attempted to save channel ${this.name} ` +
+            `but it wasn't finished loading yet!`
+        );
     }
 
     if (this.is(Flags.C_ERROR)) {
-        return Promise.reject(new Error(`Channel is in error state`));
+        throw new Error(`Channel is in error state`);
     }
 
     this.logger.log("[init] Saving channel state to disk");
+
     const data = {};
     Object.keys(this.modules).forEach(m => {
-        this.modules[m].save(data);
+        if (
+            this.modules[m].dirty ||
+            !Switches.isActive('dirtyCheck') ||
+            !this.modules[m].supportsDirtyCheck
+        ) {
+            this.modules[m].save(data);
+        } else {
+            LOGGER.debug(
+                "Skipping save for %s[%s]: not dirty",
+                this.uniqueName,
+                m
+            );
+        }
     });
 
-    return ChannelStore.save(this.id, this.uniqueName, data)
-            .catch(ChannelStateSizeError, err => {
-        this.users.forEach(u => {
-            if (u.account.effectiveRank >= 2) {
-                u.socket.emit("warnLargeChandump", {
-                    limit: err.limit,
-                    actual: err.actual
-                });
-            }
+    try {
+        await ChannelStore.save(this.id, this.uniqueName, data);
+
+        Object.keys(this.modules).forEach(m => {
+            this.modules[m].dirty = false;
         });
+    } catch (error) {
+        if (error instanceof ChannelStateSizeError) {
+            this.users.forEach(u => {
+                if (u.account.effectiveRank >= 2) {
+                    u.socket.emit("warnLargeChandump", {
+                        limit: error.limit,
+                        actual: error.actual
+                    });
+                }
+            });
+        }
 
-        throw err;
-    });
+        throw error;
+    }
 };
 
 Channel.prototype.checkModules = function (fn, args, cb) {

src/channel/chat.js

@@ -36,6 +36,7 @@ function ChatModule(channel) {
     this.buffer = [];
     this.muted = new util.Set();
     this.commandHandlers = {};
+    this.supportsDirtyCheck = true;
 
     /* Default commands */
     this.registerCommand("/me", this.handleCmdMe.bind(this));
@@ -69,6 +70,8 @@ ChatModule.prototype.load = function (data) {
             this.muted.add(data.chatmuted[i]);
         }
     }
+
+    this.dirty = false;
 };
 
 ChatModule.prototype.save = function (data) {
@@ -441,6 +444,7 @@ ChatModule.prototype.sendModMessage = function (msg, minrank) {
 ChatModule.prototype.sendMessage = function (msgobj) {
     this.channel.broadcastAll("chatMsg", msgobj);
 
+    this.dirty = true;
     this.buffer.push(msgobj);
     if (this.buffer.length > 15) {
         this.buffer.shift();
@@ -492,6 +496,7 @@ ChatModule.prototype.handleCmdClear = function (user, msg, meta) {
         return;
     }
 
+    this.dirty = true;
     this.buffer = [];
     this.channel.broadcastAll("clearchat", { clearedBy: user.getName() });
     this.sendModMessage(user.getName() + " cleared chat.", -1);

src/channel/customization.js

@@ -18,6 +18,7 @@ function CustomizationModule(channel) {
     this.css = "";
     this.js = "";
     this.motd = "";
+    this.supportsDirtyCheck = true;
 }
 
 CustomizationModule.prototype = Object.create(ChannelModule.prototype);
@@ -42,6 +43,8 @@ CustomizationModule.prototype.load = function (data) {
             this.motd = XSS.sanitizeHTML(data.motd);
         }
     }
+
+    this.dirty = false;
 };
 
 CustomizationModule.prototype.save = function (data) {
@@ -86,6 +89,7 @@ CustomizationModule.prototype.handleSetCSS = function (user, data) {
         return;
     }
 
+    this.dirty = true;
     this.css = data.css.substring(0, 20000);
     this.sendCSSJS(this.channel.users);
 
@@ -98,6 +102,7 @@ CustomizationModule.prototype.handleSetJS = function (user, data) {
         return;
     }
 
+    this.dirty = true;
     this.js = data.js.substring(0, 20000);
     this.sendCSSJS(this.channel.users);
 
@@ -112,6 +117,7 @@ CustomizationModule.prototype.handleSetMotd = function (user, data) {
 
     var motd = data.motd.substring(0, 20000);
 
+    this.dirty = true;
     this.setMotd(motd);
     this.channel.logger.log("[mod] " + user.getName() + " updated the MOTD");
 };

src/channel/emotes.js

@@ -119,6 +119,7 @@ function validateEmote(f) {
 function EmoteModule(channel) {
     ChannelModule.apply(this, arguments);
     this.emotes = new EmoteList();
+    this.supportsDirtyCheck = true;
 }
 
 EmoteModule.prototype = Object.create(ChannelModule.prototype);
@@ -129,6 +130,8 @@ EmoteModule.prototype.load = function (data) {
             this.emotes.updateEmote(data.emotes[i]);
         }
     }
+
+    this.dirty = false;
 };
 
 EmoteModule.prototype.save = function (data) {
@@ -198,6 +201,8 @@ EmoteModule.prototype.handleRenameEmote = function (user, data) {
     var success = this.emotes.renameEmote(Object.assign({}, f));
     if(!success){ return; }
 
+    this.dirty = true;
+
     var chan = this.channel;
     chan.broadcastAll("renameEmote", f);
     chan.logger.log(`[mod] ${user.getName()} renamed emote: ${f.old} -> ${f.name}`);
@@ -228,6 +233,9 @@ EmoteModule.prototype.handleUpdateEmote = function (user, data) {
     }
 
     this.emotes.updateEmote(f);
+
+    this.dirty = true;
+
     var chan = this.channel;
     chan.broadcastAll("updateEmote", f);
 
@@ -249,6 +257,9 @@ EmoteModule.prototype.handleImportEmotes = function (user, data) {
     this.emotes.importList(data.map(validateEmote).filter(function (f) {
         return f !== false;
     }));
+
+    this.dirty = true;
+
     this.sendEmotes(this.channel.users);
 };
 
@@ -266,6 +277,9 @@ EmoteModule.prototype.handleRemoveEmote = function (user, data) {
     }
 
     this.emotes.removeEmote(data);
+
+    this.dirty = true;
+
     this.channel.logger.log("[mod] " + user.getName() + " removed emote: " + data.name);
     this.channel.broadcastAll("removeEmote", data);
 };
@@ -284,6 +298,8 @@ EmoteModule.prototype.handleMoveEmote = function (user, data) {
     }
 
     this.emotes.moveEmote(data.from, data.to);
+
+    this.dirty = true;
 };
 
 module.exports = EmoteModule;

src/channel/filters.js

@@ -65,6 +65,7 @@ const DEFAULT_FILTERS = [
 function ChatFilterModule(channel) {
     ChannelModule.apply(this, arguments);
     this.filters = new FilterList();
+    this.supportsDirtyCheck = true;
 }
 
 ChatFilterModule.prototype = Object.create(ChannelModule.prototype);
@@ -84,6 +85,8 @@ ChatFilterModule.prototype.load = function (data) {
     } else {
         this.filters = new FilterList(DEFAULT_FILTERS);
     }
+
+    this.dirty = false;
 };
 
 ChatFilterModule.prototype.save = function (data) {
@@ -149,6 +152,8 @@ ChatFilterModule.prototype.handleAddFilter = function (user, data) {
         return;
     }
 
+    this.dirty = true;
+
     user.socket.emit("addFilterSuccess");
 
     var chan = this.channel;
@@ -197,6 +202,8 @@ ChatFilterModule.prototype.handleUpdateFilter = function (user, data) {
         return;
     }
 
+    this.dirty = true;
+
     var chan = this.channel;
     chan.users.forEach(function (u) {
         if (chan.modules.permissions.canEditFilters(u)) {
@@ -232,6 +239,8 @@ ChatFilterModule.prototype.handleImportFilters = function (user, data) {
         return;
     }
 
+    this.dirty = true;
+
     this.channel.logger.log("[mod] " + user.getName() + " imported the filter list");
     this.sendChatFilters(this.channel.users);
 };
@@ -258,6 +267,9 @@ ChatFilterModule.prototype.handleRemoveFilter = function (user, data) {
         });
         return;
     }
+
+    this.dirty = true;
+
     var chan = this.channel;
     chan.users.forEach(function (u) {
         if (chan.modules.permissions.canEditFilters(u)) {
@@ -290,6 +302,8 @@ ChatFilterModule.prototype.handleMoveFilter = function (user, data) {
         });
         return;
     }
+
+    this.dirty = true;
 };
 
 ChatFilterModule.prototype.handleRequestChatFilters = function (user) {

src/channel/module.js

@@ -1,5 +1,7 @@
 function ChannelModule(channel) {
     this.channel = channel;
+    this.dirty = false;
+    this.supportsDirtyCheck = false;
 }
 
 ChannelModule.prototype = {

src/channel/opts.js

@@ -34,6 +34,8 @@ function OptionsModule(channel) {
         new_user_chat_link_delay: 0, // Minimum account/IP age to post links
         playlist_max_duration_per_user: 0 // Maximum total playlist time per user
     };
+
+    this.supportsDirtyCheck = true;
 }
 
 OptionsModule.prototype = Object.create(ChannelModule.prototype);
@@ -51,6 +53,7 @@ OptionsModule.prototype.load = function (data) {
             this.opts.chat_antiflood_params.burst);
     this.opts.chat_antiflood_params.sustained = Math.min(10,
             this.opts.chat_antiflood_params.sustained);
+    this.dirty = false;
 };
 
 OptionsModule.prototype.save = function (data) {
@@ -356,6 +359,7 @@ OptionsModule.prototype.handleSetOptions = function (user, data) {
 
     this.channel.logger.log("[mod] " + user.getName() + " updated channel options");
     if (sendUpdate) {
+        this.dirty = true;
         this.sendOpts(this.channel.users);
     }
 };

src/channel/permissions.js

@@ -50,6 +50,7 @@ function PermissionsModule(channel) {
     ChannelModule.apply(this, arguments);
     this.permissions = {};
     this.openPlaylist = false;
+    this.supportsDirtyCheck = true;
 }
 
 PermissionsModule.prototype = Object.create(ChannelModule.prototype);
@@ -70,6 +71,8 @@ PermissionsModule.prototype.load = function (data) {
     } else if ("playlistLock" in data) {
         this.openPlaylist = !data.playlistLock;
     }
+
+    this.dirty = false;
 };
 
 PermissionsModule.prototype.save = function (data) {
@@ -124,6 +127,7 @@ PermissionsModule.prototype.handleTogglePlaylistLock = function (user) {
         return;
     }
 
+    this.dirty = true;
     this.openPlaylist = !this.openPlaylist;
     if (this.openPlaylist) {
         this.channel.logger.log("[playlist] " + user.getName() + " unlocked the playlist");
@@ -165,6 +169,7 @@ PermissionsModule.prototype.handleSetPermissions = function (user, perms) {
         }
     }
 
+    this.dirty = true;
     this.channel.logger.log("[mod] " + user.getName() + " updated permissions");
     this.sendPermissions(this.channel.users);
 };

src/channel/poll.js

@@ -28,6 +28,7 @@ function PollModule(channel) {
         this.channel.modules.chat.registerCommand("poll", this.handlePollCmd.bind(this, false));
         this.channel.modules.chat.registerCommand("hpoll", this.handlePollCmd.bind(this, true));
     }
+    this.supportsDirtyCheck = true;
 }
 
 PollModule.prototype = Object.create(ChannelModule.prototype);
@@ -49,6 +50,8 @@ PollModule.prototype.load = function (data) {
             this.poll.timestamp = data.poll.timestamp;
         }
     }
+
+    this.dirty = false;
 };
 
 PollModule.prototype.save = function (data) {
@@ -197,6 +200,7 @@ PollModule.prototype.handleNewPoll = function (user, data, ack) {
     }
 
     this.poll = poll;
+    this.dirty = true;
     this.broadcastPoll(true);
     this.channel.logger.log("[poll] " + user.getName() + " opened poll: '" + poll.title + "'");
     ack({});
@@ -209,6 +213,7 @@ PollModule.prototype.handleVote = function (user, data) {
 
     if (this.poll) {
         this.poll.vote(user.realip, data.option);
+        this.dirty = true;
         this.broadcastPoll(false);
     }
 };
@@ -231,6 +236,7 @@ PollModule.prototype.handleClosePoll = function (user) {
         this.channel.broadcastAll("closePoll");
         this.channel.logger.log("[poll] " + user.getName() + " closed the active poll");
         this.poll = null;
+        this.dirty = true;
     }
 };
 
@@ -255,6 +261,7 @@ PollModule.prototype.handlePollCmd = function (obscured, user, msg, meta) {
 
     var poll = new Poll(user.getName(), title, args, obscured);
     this.poll = poll;
+    this.dirty = true;
     this.broadcastPoll(true);
     this.channel.logger.log("[poll] " + user.getName() + " opened poll: '" + poll.title + "'");
 };