Add example extension for chat variables. Allow registering custom text processing functions for extensions

public/scripts/extensions.js

@@ -1,5 +1,5 @@
 import { callPopup, eventSource, event_types, saveSettings, saveSettingsDebounced, getRequestHeaders } from "../script.js";
-import { isSubsetOf, debounce } from "./utils.js";
+import { isSubsetOf, debounce, waitUntilCondition } from "./utils.js";
 export {
     getContext,
     getApiUrl,
@@ -16,6 +16,42 @@ let manifests = [];
 const defaultUrl = "http://localhost:5100";
 export const saveMetadataDebounced = debounce(async () => await getContext().saveMetadata(), 1000);
 
+export const extensionsHandlebars = Handlebars.create();
+
+/**
+ * Registers a Handlebars helper for use in extensions.
+ * @param {string} name Handlebars helper name
+ * @param {function} helper Handlebars helper function
+ */
+export function registerExtensionHelper(name, helper) {
+    extensionsHandlebars.registerHelper(name, helper);
+}
+
+/**
+ * Applies handlebars extension helpers to a message.
+ * @param {number} messageId Message index in the chat.
+ */
+function processExtensionHelpers(messageId) {
+    const context = getContext();
+    const message = context.chat[messageId];
+
+    if (!message?.mes || typeof message.mes !== 'string') {
+        return;
+    }
+
+    // Don't waste time if there are no mustaches
+    if (!message.mes.includes('{{')) {
+        return;
+    }
+
+    try {
+        const template = extensionsHandlebars.compile(message.mes, { noEscape: true });
+        message.mes = template({});
+    } catch {
+        // Ignore
+    }
+}
+
 // Disables parallel updates
 class ModuleWorkerWrapper {
     constructor(callback) {
@@ -629,10 +665,13 @@ async function runGenerationInterceptors(chat, contextSize) {
     }
 }
 
-$(document).ready(async function () {
-    setTimeout(function () {
+jQuery(function () {
+    setTimeout(async function () {
         addExtensionsButtonAndMenu();
         $("#extensionsMenuButton").css("display", "flex");
+        await waitUntilCondition(() => eventSource !== undefined, 1000, 100);
+        eventSource.on(event_types.MESSAGE_RECEIVED, processExtensionHelpers);
+        eventSource.on(event_types.MESSAGE_SENT, processExtensionHelpers);
     }, 100)
 
     $("#extensions_connect").on('click', connectClickHandler);

public/scripts/extensions/variables/index.js

@@ -0,0 +1,62 @@
+import { getContext } from "../../extensions.js";
+
+/**
+ * Gets a chat variable from the current chat metadata.
+ * @param {string} name The name of the variable to get.
+ * @returns {string} The value of the variable.
+ */
+function getChatVariable(name) {
+    const metadata = getContext().chatMetadata;
+
+    if (!metadata) {
+        return '';
+    }
+
+    if (!metadata.variables) {
+        metadata.variables = {};
+        return '';
+    }
+
+    return metadata.variables[name] || '';
+}
+
+/**
+ * Sets a chat variable in the current chat metadata.
+ * @param {string} name The name of the variable to set.
+ * @param {any} value The value of the variable to set.
+ */
+function setChatVariable(name, value) {
+    const metadata = getContext().chatMetadata;
+
+    if (!metadata) {
+        return;
+    }
+
+    if (!metadata.variables) {
+        metadata.variables = {};
+    }
+
+    metadata.variables[name] = value;
+}
+
+function listChatVariables() {
+    const metadata = getContext().chatMetadata;
+
+    if (!metadata) {
+        return '';
+    }
+
+    if (!metadata.variables) {
+        metadata.variables = {};
+        return '';
+    }
+
+    return Object.keys(metadata.variables).map(key => `${key}=${metadata.variables[key]}`).join(';');
+}
+
+jQuery(() => {
+    const context = getContext();
+    context.registerHelper('getvar', getChatVariable);
+    context.registerHelper('setvar', setChatVariable);
+    context.registerHelper('listvar', listChatVariables);
+});

public/scripts/extensions/variables/manifest.json

@@ -0,0 +1,11 @@
+{
+    "display_name": "Chat Variables",
+    "loading_order": 100,
+    "requires": [],
+    "optional": [],
+    "js": "index.js",
+    "css": "",
+    "author": "Cohee#1207",
+    "version": "1.0.0",
+    "homePage": "https://github.com/SillyTavern/SillyTavern"
+}

public/scripts/openai.js

@@ -1088,8 +1088,8 @@ async function sendAltScaleRequest(openai_msgs_tosend, logit_bias, signal) {
     const generate_url = '/generate_altscale';
 
     let firstSysMsgs = []
-    for(let msg of openai_msgs_tosend){
-        if(msg.role === 'system') {
+    for (let msg of openai_msgs_tosend) {
+        if (msg.role === 'system') {
             firstSysMsgs.push(substituteParams(msg.name ? msg.name + ": " + msg.content : msg.content));
         } else {
             break;
@@ -2587,7 +2587,7 @@ function onSettingsPresetChange() {
         use_ai21_tokenizer: ['#use_ai21_tokenizer', 'use_ai21_tokenizer', false],
         exclude_assistant: ['#exclude_assistant', 'exclude_assistant', false],
         use_alt_scale: ['#use_alt_scale', 'use_alt_scale', false],
-        };
+    };
 
     const presetName = $('#settings_perset_openai').find(":selected").text();
     oai_settings.preset_settings_openai = presetName;

public/scripts/slash-commands.js

@@ -338,8 +338,8 @@ async function sendMessageAs(_, text) {
     };
 
     chat.push(message);
-    addOneMessage(message);
     await eventSource.emit(event_types.MESSAGE_SENT, (chat.length - 1));
+    addOneMessage(message);
     saveChatConditional();
 }
 
@@ -369,8 +369,8 @@ async function sendNarratorMessage(_, text) {
     };
 
     chat.push(message);
-    addOneMessage(message);
     await eventSource.emit(event_types.MESSAGE_SENT, (chat.length - 1));
+    addOneMessage(message);
     saveChatConditional();
 }
 
@@ -394,8 +394,8 @@ async function sendCommentMessage(_, text) {
     };
 
     chat.push(message);
-    addOneMessage(message);
     await eventSource.emit(event_types.MESSAGE_SENT, (chat.length - 1));
+    addOneMessage(message);
     saveChatConditional();
 }