Finish implementation of webllm

libs/langchain-community/langchain.config.js

@@ -166,6 +166,7 @@ export const config = {
     "chat_models/portkey": "chat_models/portkey",
     "chat_models/premai": "chat_models/premai",
     "chat_models/togetherai": "chat_models/togetherai",
+    "chat_models/webllm": "chat_models/webllm",
     "chat_models/yandex": "chat_models/yandex",
     "chat_models/zhipuai": "chat_models/zhipuai",
     // callbacks

libs/langchain-community/package.json

@@ -75,7 +75,7 @@
     "@huggingface/inference": "^2.6.4",
     "@jest/globals": "^29.5.0",
     "@langchain/scripts": "~0.0",
-    "@mlc-ai/web-llm": "0.2.28",
+    "@mlc-ai/web-llm": "^0.2.28",
     "@mozilla/readability": "^0.4.4",
     "@neondatabase/serverless": "^0.9.1",
     "@opensearch-project/opensearch": "^2.2.0",
@@ -205,7 +205,7 @@
     "@google-ai/generativelanguage": "^0.2.1",
     "@gradientai/nodejs-sdk": "^1.2.0",
     "@huggingface/inference": "^2.6.4",
-    "@mlc-ai/web-llm": "0.2.28",
+    "@mlc-ai/web-llm": "^0.2.28",
     "@mozilla/readability": "*",
     "@neondatabase/serverless": "*",
     "@opensearch-project/opensearch": "*",

libs/langchain-community/src/chat_models/webllm.ts

@@ -6,11 +6,7 @@ import type { BaseLanguageModelCallOptions } from "@langchain/core/language_mode
 import { CallbackManagerForLLMRun } from "@langchain/core/callbacks/manager";
 import { BaseMessage, AIMessageChunk } from "@langchain/core/messages";
 import { ChatGenerationChunk } from "@langchain/core/outputs";
-import {
-  ChatModule,
-  type ModelRecord,
-  InitProgressCallback,
-} from "@mlc-ai/web-llm";
+import * as webllm from '@mlc-ai/web-llm'
 import { ChatCompletionMessageParam } from '@mlc-ai/web-llm/lib/openai_api_protocols'
 
 // Code from jacoblee93 https://github.com/jacoblee93/fully-local-pdf-chatbot/blob/main/app/lib/chat_models/webllm.ts
@@ -20,7 +16,9 @@ import { ChatCompletionMessageParam } from '@mlc-ai/web-llm/lib/openai_api_proto
  * can set this in the environment variable `LLAMA_PATH`.
  */
 export interface WebLLMInputs extends BaseChatModelParams {
-  modelRecord: ModelRecord;
+  appConfig?: webllm.AppConfig;
+  chatOpts?: webllm.ChatOptions;
+  modelRecord: webllm.ModelRecord;
   temperature?: number;
 }
 
@@ -31,16 +29,19 @@ export interface WebLLMCallOptions extends BaseLanguageModelCallOptions {}
  *  This can be installed using `npm install -S @mlc-ai/web-llm`
  * @example
  * ```typescript
- * // Initialize the ChatWebLLM model with the model record.
+ * // Initialize the ChatWebLLM model with the model record and chat options.
+ * // Note that if the appConfig field is set, the list of model records 
+ * // must include the selected model record for the engine.
  * const model = new ChatWebLLM({
  *   modelRecord: {
- *     "model_url": "https://huggingface.co/mlc-ai/phi-2-q4f32_1-MLC/resolve/main/",
- *     "local_id": "Phi2-q4f32_1",
- *     "model_lib_url": "https://raw.githubusercontent.com/mlc-ai/binary-mlc-llm-libs/main/phi-2/phi-2-q4f32_1-ctx2k-webgpu.wasm",
- *     "vram_required_MB": 4032.48,
- *     "low_resource_required": false,
+ *     "model_url": "https://huggingface.co/mlc-ai/Llama-3-8B-Instruct-q4f32_1-MLC/resolve/main/",
+ *     "model_id": "Llama-3-8B-Instruct-q4f32_1",
+ *     "model_lib_url": webllm.modelLibURLPrefix + webllm.modelVersion + "/Llama-3-8B-Instruct-q4f32_1-ctx4k_cs1k-webgpu.wasm,
  *   },
- *   temperature: 0.5,
+ *   chatOpts: {
+ *     temperature: 0.5,
+ *     top-p: 2
+ *   }
  * });
  *
  * // Call the model with a message and await the response.
@@ -52,39 +53,54 @@ export interface WebLLMCallOptions extends BaseLanguageModelCallOptions {}
 export class ChatWebLLM extends SimpleChatModel<WebLLMCallOptions> {
   static inputs: WebLLMInputs;
 
-  protected _chatModule: ChatModule;
+  protected engine: webllm.EngineInterface;
 
-  modelRecord: ModelRecord;
+  /**
+   * Configures list of models available to engine via list of ModelRecords.
+   * @example
+   */
+  // const appConfig: webllm.AppConfig = {
+  //   model_list: [
+  //     {
+  //       "model_url": "https://huggingface.co/mlc-ai/Llama-3-8B-Instruct-q4f32_1-MLC/resolve/main/",
+  //       "model_id": "Llama-3-8B-Instruct-q4f32_1",
+  //       "model_lib_url": webllm.modelLibURLPrefix + webllm.modelVersion + "/Llama-3-8B-Instruct-q4f32_1-ctx4k_cs1k-webgpu.wasm",
+  //     },
+  //   ]
+  // };
+  appConfig?: webllm.AppConfig;
 
-  temperature?: number;
+  /**
+   * Configures model options (temperature, etc.).
+   */
+  chatOpts?: webllm.ChatOptions;
+
+  modelRecord: webllm.ModelRecord;
 
   static lc_name() {
     return "ChatWebLLM";
   }
 
   constructor(inputs: WebLLMInputs) {
     super(inputs);
-    this._chatModule = new ChatModule();
+    this.appConfig = inputs.appConfig;
+    this.chatOpts = inputs.chatOpts;
     this.modelRecord = inputs.modelRecord;
-    this.temperature = inputs.temperature;
   }
 
   _llmType() {
-    return "web-llm";
+    return "ChatWebLLM: " + this.modelRecord.model_id
   }
 
-  _modelType() {
-    return this.modelRecord.local_id
+  async initialize() {
+    this.engine = webllm.Engine().reload(this.modelRecord.model_id, this.appConfig, this.chatOpts)
+    this.engine.setInitProgressCallback(() => {})
   }
 
-  async initialize(progressCallback?: InitProgressCallback) {
-    if (progressCallback !== undefined) {
-      this._chatModule.setInitProgressCallback(progressCallback);
-    }
-    await this._chatModule.reload(this.modelRecord.local_id, undefined, {
-      model_list: [this.modelRecord],
-    });
-    this._chatModule.setInitProgressCallback(() => {});
+  async reload(newModelRecord: webllm.ModelRecord, newAppConfig?: webllm.AppConfig, newChatOpts?: webllm.ChatOptions) {
+    if (this.engine !== undefined) {
+      this.engine.reload(newModelRecord.model_id, newAppConfig, newChatOpts)
+    } else throw new Error("Initialize model before reloading.")
   }
 
   async *_streamResponseChunks(
@@ -120,23 +136,25 @@ export class ChatWebLLM extends SimpleChatModel<WebLLMCallOptions> {
         };
       },
     );
-    const stream = this._chatModule.chatCompletionAsyncChunkGenerator(
+
+    const stream = this.engine.chat.completions.create(
       {
         stream: true,
         messages: messagesInput,
         stop: options.stop,
-        temperature: this.temperature,
-      },
-      {},
+        logprobs: true
+      }
     );
     for await (const chunk of stream) {
+      // Last chunk has undefined content
       const text = chunk.choices[0].delta.content ?? "";
       yield new ChatGenerationChunk({
         text,
         message: new AIMessageChunk({
           content: text,
           additional_kwargs: {
             logprobs: chunk.choices[0].logprobs,
+            finish_reason: chunk.choices[0].finish_reason
           },
         }),
       });

yarn.lock

@@ -8953,7 +8953,7 @@ __metadata:
     "@langchain/core": ~0.1.60
     "@langchain/openai": ~0.0.28
     "@langchain/scripts": ~0.0
-    "@mlc-ai/web-llm": 0.2.28
+    "@mlc-ai/web-llm": ^0.2.28
     "@mozilla/readability": ^0.4.4
     "@neondatabase/serverless": ^0.9.1
     "@opensearch-project/opensearch": ^2.2.0
@@ -9088,7 +9088,7 @@ __metadata:
     "@google-ai/generativelanguage": ^0.2.1
     "@gradientai/nodejs-sdk": ^1.2.0
     "@huggingface/inference": ^2.6.4
-    "@mlc-ai/web-llm": 0.2.28
+    "@mlc-ai/web-llm": ^0.2.28
     "@mozilla/readability": "*"
     "@neondatabase/serverless": "*"
     "@opensearch-project/opensearch": "*"
@@ -10115,10 +10115,10 @@ __metadata:
   languageName: node
   linkType: hard
 
-"@mlc-ai/web-llm@npm:0.2.28":
-  version: 0.2.28
-  resolution: "@mlc-ai/web-llm@npm:0.2.28"
-  checksum: 18188e18c5866e6cccbba587d04329c71215134fb184b6e9d285a76b6978218d8eed071511c11ae71153ba8bcda333bd4b10bbdce77f07a05e269e372d235f0e
+"@mlc-ai/web-llm@npm:^0.2.28":
+  version: 0.2.35
+  resolution: "@mlc-ai/web-llm@npm:0.2.35"
+  checksum: 03c1d1847340f88474e1eeed7a91cc09e29299a1216e378385ffe5479c203d39a8656d98c9187864322453a91f046b874d7073662ab04033527079d9bb29bee3
   languageName: node
   linkType: hard