Refactoring AIProvider and handling errors (#15)

* Better handling of error with providers

* Add a method to get the error message when catching an error

src/chat-handler.ts

@@ -16,6 +16,8 @@ import {
   mergeMessageRuns
 } from '@langchain/core/messages';
 import { UUID } from '@lumino/coreutils';
+import { getErrorMessage } from './llm-models';
+import { IAIProvider } from './token';
 
 export type ConnectionMessage = {
   type: 'connection';
@@ -25,14 +27,14 @@ export type ConnectionMessage = {
 export class ChatHandler extends ChatModel {
   constructor(options: ChatHandler.IOptions) {
     super(options);
-    this._provider = options.provider;
+    this._aiProvider = options.aiProvider;
+    this._aiProvider.modelChange.connect(() => {
+      this._errorMessage = this._aiProvider.chatError;
+    });
   }
 
   get provider(): BaseChatModel | null {
-    return this._provider;
-  }
-  set provider(provider: BaseChatModel | null) {
-    this._provider = provider;
+    return this._aiProvider.chatModel;
   }
 
   async sendMessage(message: INewMessage): Promise<boolean> {
@@ -46,15 +48,15 @@ export class ChatHandler extends ChatModel {
     };
     this.messageAdded(msg);
 
-    if (this._provider === null) {
-      const botMsg: IChatMessage = {
+    if (this._aiProvider.chatModel === null) {
+      const errorMsg: IChatMessage = {
         id: UUID.uuid4(),
-        body: '**AI provider not configured for the chat**',
+        body: `**${this._errorMessage ? this._errorMessage : this._defaultErrorMessage}**`,
         sender: { username: 'ERROR' },
         time: Date.now(),
         type: 'msg'
       };
-      this.messageAdded(botMsg);
+      this.messageAdded(errorMsg);
       return false;
     }
 
@@ -69,19 +71,37 @@ export class ChatHandler extends ChatModel {
       })
     );
 
-    const response = await this._provider.invoke(messages);
-    // TODO: fix deprecated response.text
-    const content = response.text;
-    const botMsg: IChatMessage = {
-      id: UUID.uuid4(),
-      body: content,
-      sender: { username: 'Bot' },
-      time: Date.now(),
-      type: 'msg'
-    };
-    this.messageAdded(botMsg);
-    this._history.messages.push(botMsg);
-    return true;
+    this.updateWriters([{ username: 'AI' }]);
+    return this._aiProvider.chatModel
+      .invoke(messages)
+      .then(response => {
+        const content = response.content;
+        const botMsg: IChatMessage = {
+          id: UUID.uuid4(),
+          body: content.toString(),
+          sender: { username: 'AI' },
+          time: Date.now(),
+          type: 'msg'
+        };
+        this.messageAdded(botMsg);
+        this._history.messages.push(botMsg);
+        return true;
+      })
+      .catch(reason => {
+        const error = getErrorMessage(this._aiProvider.name, reason);
+        const errorMsg: IChatMessage = {
+          id: UUID.uuid4(),
+          body: `**${error}**`,
+          sender: { username: 'ERROR' },
+          time: Date.now(),
+          type: 'msg'
+        };
+        this.messageAdded(errorMsg);
+        return false;
+      })
+      .finally(() => {
+        this.updateWriters([]);
+      });
   }
 
   async getHistory(): Promise<IChatHistory> {
@@ -96,12 +116,14 @@ export class ChatHandler extends ChatModel {
     super.messageAdded(message);
   }
 
-  private _provider: BaseChatModel | null;
+  private _aiProvider: IAIProvider;
+  private _errorMessage: string = '';
   private _history: IChatHistory = { messages: [] };
+  private _defaultErrorMessage = 'AI provider not configured';
 }
 
 export namespace ChatHandler {
   export interface IOptions extends ChatModel.IOptions {
-    provider: BaseChatModel | null;
+    aiProvider: IAIProvider;
   }
 }

src/completion-provider.ts

@@ -5,7 +5,8 @@ import {
 } from '@jupyterlab/completer';
 import { LLM } from '@langchain/core/language_models/llms';
 
-import { getCompleter, IBaseCompleter } from './llm-models';
+import { getCompleter, IBaseCompleter, BaseCompleter } from './llm-models';
+import { ReadonlyPartialJSONObject } from '@lumino/coreutils';
 
 /**
  * The generic completion provider to register to the completion provider manager.
@@ -14,23 +15,36 @@ export class CompletionProvider implements IInlineCompletionProvider {
   readonly identifier = '@jupyterlite/ai';
 
   constructor(options: CompletionProvider.IOptions) {
-    this.name = options.name;
+    const { name, settings } = options;
+    this.setCompleter(name, settings);
   }
 
   /**
-   * Getter and setter of the name.
-   * The setter will create the appropriate completer, accordingly to the name.
+   * Set the completer.
+   *
+   * @param name - the name of the completer.
+   * @param settings - The settings associated to the completer.
+   */
+  setCompleter(name: string, settings: ReadonlyPartialJSONObject) {
+    try {
+      this._completer = getCompleter(name, settings);
+      this._name = this._completer === null ? 'None' : name;
+    } catch (e: any) {
+      this._completer = null;
+      this._name = 'None';
+      throw e;
+    }
+  }
+
+  /**
+   * Get the current completer name.
    */
   get name(): string {
     return this._name;
   }
-  set name(name: string) {
-    this._name = name;
-    this._completer = getCompleter(name);
-  }
 
   /**
-   * get the current completer.
+   * Get the current completer.
    */
   get completer(): IBaseCompleter | null {
     return this._completer;
@@ -55,7 +69,7 @@ export class CompletionProvider implements IInlineCompletionProvider {
 }
 
 export namespace CompletionProvider {
-  export interface IOptions {
+  export interface IOptions extends BaseCompleter.IOptions {
     name: string;
   }
 }

src/index.ts

@@ -41,14 +41,10 @@ const chatPlugin: JupyterFrontEndPlugin<void> = {
     }
 
     const chatHandler = new ChatHandler({
-      provider: aiProvider.chatModel,
+      aiProvider: aiProvider,
       activeCellManager: activeCellManager
     });
 
-    aiProvider.modelChange.connect(() => {
-      chatHandler.provider = aiProvider.chatModel;
-    });
-
     let sendWithShiftEnter = false;
     let enableCodeToolbar = true;
 

src/llm-models/base-completer.ts

@@ -3,6 +3,7 @@ import {
   IInlineCompletionContext
 } from '@jupyterlab/completer';
 import { LLM } from '@langchain/core/language_models/llms';
+import { ReadonlyPartialJSONObject } from '@lumino/coreutils';
 
 export interface IBaseCompleter {
   /**
@@ -18,3 +19,15 @@ export interface IBaseCompleter {
     context: IInlineCompletionContext
   ): Promise<any>;
 }
+
+/**
+ * The namespace for the base completer.
+ */
+export namespace BaseCompleter {
+  /**
+   * The options for the constructor of a completer.
+   */
+  export interface IOptions {
+    settings: ReadonlyPartialJSONObject;
+  }
+}

src/llm-models/codestral-completer.ts

@@ -7,19 +7,16 @@ import { MistralAI } from '@langchain/mistralai';
 import { Throttler } from '@lumino/polling';
 import { CompletionRequest } from '@mistralai/mistralai';
 
-import { IBaseCompleter } from './base-completer';
+import { BaseCompleter, IBaseCompleter } from './base-completer';
 
 /*
  * The Mistral API has a rate limit of 1 request per second
  */
 const INTERVAL = 1000;
 
 export class CodestralCompleter implements IBaseCompleter {
-  constructor() {
-    this._mistralProvider = new MistralAI({
-      apiKey: 'TMP',
-      model: 'codestral-latest'
-    });
+  constructor(options: BaseCompleter.IOptions) {
+    this._mistralProvider = new MistralAI({ ...options.settings });
     this._throttler = new Throttler(async (data: CompletionRequest) => {
       const response = await this._mistralProvider.completionWithRetry(
         data,

src/llm-models/utils.ts

@@ -2,23 +2,40 @@ import { BaseChatModel } from '@langchain/core/language_models/chat_models';
 import { ChatMistralAI } from '@langchain/mistralai';
 import { IBaseCompleter } from './base-completer';
 import { CodestralCompleter } from './codestral-completer';
+import { ReadonlyPartialJSONObject } from '@lumino/coreutils';
 
 /**
  * Get an LLM completer from the name.
  */
-export function getCompleter(name: string): IBaseCompleter | null {
+export function getCompleter(
+  name: string,
+  settings: ReadonlyPartialJSONObject
+): IBaseCompleter | null {
   if (name === 'MistralAI') {
-    return new CodestralCompleter();
+    return new CodestralCompleter({ settings });
   }
   return null;
 }
 
 /**
  * Get an LLM chat model from the name.
  */
-export function getChatModel(name: string): BaseChatModel | null {
+export function getChatModel(
+  name: string,
+  settings: ReadonlyPartialJSONObject
+): BaseChatModel | null {
   if (name === 'MistralAI') {
-    return new ChatMistralAI({ apiKey: 'TMP' });
+    return new ChatMistralAI({ ...settings });
   }
   return null;
 }
+
+/**
+ * Get the error message from provider.
+ */
+export function getErrorMessage(name: string, error: any): string {
+  if (name === 'MistralAI') {
+    return error.message;
+  }
+  return 'Unknown provider';
+}

src/provider.ts

@@ -10,7 +10,10 @@ import { IAIProvider } from './token';
 
 export class AIProvider implements IAIProvider {
   constructor(options: AIProvider.IOptions) {
-    this._completionProvider = new CompletionProvider({ name: 'None' });
+    this._completionProvider = new CompletionProvider({
+      name: 'None',
+      settings: {}
+    });
     options.completionProviderManager.registerInlineProvider(
       this._completionProvider
     );
@@ -21,7 +24,7 @@ export class AIProvider implements IAIProvider {
   }
 
   /**
-   * get the current completer of the completion provider.
+   * Get the current completer of the completion provider.
    */
   get completer(): IBaseCompleter | null {
     if (this._name === null) {
@@ -31,7 +34,7 @@ export class AIProvider implements IAIProvider {
   }
 
   /**
-   * get the current llm chat model.
+   * Get the current llm chat model.
    */
   get chatModel(): BaseChatModel | null {
     if (this._name === null) {
@@ -40,6 +43,20 @@ export class AIProvider implements IAIProvider {
     return this._llmChatModel;
   }
 
+  /**
+   * Get the current chat error;
+   */
+  get chatError(): string {
+    return this._chatError;
+  }
+
+  /**
+   * get the current completer error.
+   */
+  get completerError(): string {
+    return this._completerError;
+  }
+
   /**
    * Set the models (chat model and completer).
    * Creates the models if the name has changed, otherwise only updates their config.
@@ -48,22 +65,21 @@ export class AIProvider implements IAIProvider {
    * @param settings - the settings for the models.
    */
   setModels(name: string, settings: ReadonlyPartialJSONObject) {
-    if (name !== this._name) {
-      this._name = name;
-      this._completionProvider.name = name;
-      this._llmChatModel = getChatModel(name);
-      this._modelChange.emit();
+    try {
+      this._completionProvider.setCompleter(name, settings);
+      this._completerError = '';
+    } catch (e: any) {
+      this._completerError = e.message;
     }
-
-    // Update the inline completion provider settings.
-    if (this._completionProvider.llmCompleter) {
-      AIProvider.updateConfig(this._completionProvider.llmCompleter, settings);
-    }
-
-    // Update the chat LLM settings.
-    if (this._llmChatModel) {
-      AIProvider.updateConfig(this._llmChatModel, settings);
+    try {
+      this._llmChatModel = getChatModel(name, settings);
+      this._chatError = '';
+    } catch (e: any) {
+      this._chatError = e.message;
+      this._llmChatModel = null;
     }
+    this._name = name;
+    this._modelChange.emit();
   }
 
   get modelChange(): ISignal<IAIProvider, void> {
@@ -74,6 +90,8 @@ export class AIProvider implements IAIProvider {
   private _llmChatModel: BaseChatModel | null = null;
   private _name: string = 'None';
   private _modelChange = new Signal<IAIProvider, void>(this);
+  private _chatError: string = '';
+  private _completerError: string = '';
 }
 
 export namespace AIProvider {

src/token.ts

@@ -5,10 +5,12 @@ import { ISignal } from '@lumino/signaling';
 import { IBaseCompleter } from './llm-models';
 
 export interface IAIProvider {
-  name: string | null;
+  name: string;
   completer: IBaseCompleter | null;
   chatModel: BaseChatModel | null;
   modelChange: ISignal<IAIProvider, void>;
+  chatError: string;
+  completerError: string;
 }
 
 export const IAIProvider = new Token<IAIProvider>(