Add ESLint to Prompt API Polyfill

built-in-ai-extension/package.json

@@ -15,16 +15,16 @@
   "author": "Thomas Steiner (tomac@google.com)",
   "license": "Apache-2.0",
   "dependencies": {
-    "built-in-ai-task-apis-polyfills": "^1.4.0",
-    "prompt-api-polyfill": "^1.10.0"
+    "built-in-ai-task-apis-polyfills": "^1.5.0",
+    "prompt-api-polyfill": "^1.11.0"
   },
   "devDependencies": {
     "@eslint/js": "^10.0.1",
     "eslint": "^10.0.2",
     "eslint-config-google": "^0.14.0",
     "eslint-config-prettier": "^10.1.8",
     "globals": "^17.3.0",
-    "node-addon-api": "^8.5.0",
+    "node-addon-api": "^8.6.0",
     "node-gyp": "^12.2.0",
     "prettier": "^3.8.1",
     "vite": "^7.3.1"

built-in-ai-task-apis-polyfills/package.json

@@ -55,14 +55,14 @@
   "homepage": "https://github.com/GoogleChromeLabs/web-ai-demos/tree/main/built-in-ai-task-apis-polyfills#readme",
   "bugs": "https://github.com/GoogleChromeLabs/web-ai-demos/issues",
   "dependencies": {
-    "prompt-api-polyfill": "^1.10.0"
+    "prompt-api-polyfill": "^1.11.0"
   },
   "devDependencies": {
     "@eslint/js": "^10.0.1",
     "eslint": "^10.0.2",
     "eslint-config-prettier": "^10.1.8",
     "globals": "^17.3.0",
-    "node-addon-api": "^8.5.0",
+    "node-addon-api": "^8.6.0",
     "node-gyp": "^12.2.0",
     "prettier-plugin-curly": "^0.4.1",
     "vite": "^7.3.1"

prompt-api-polyfill/backends/base.js

@@ -7,7 +7,6 @@
  * Abstract class representing a backend for the LanguageModel polyfill.
  */
 export default class PolyfillBackend {
-  #model;
 
   /**
    * @param {string} modelName - The name of the model.
@@ -18,48 +17,48 @@ export default class PolyfillBackend {
 
   /**
    * Checks if the backend is available given the options.
-   * @param {Object} options - LanguageModel options.
+   * @param {Object} _options - LanguageModel options.
    * @returns {string} 'available', 'unavailable', 'downloadable', or 'downloading'.
    */
-  static availability(options) {
+  static availability(_options) {
     return 'available';
   }
 
   /**
    * Creates a model session and stores it.
-   * @param {Object} options - LanguageModel options.
-   * @param {Object} sessionParams - Parameters for the cloud or local model.
-   * @param {EventTarget} [monitorTarget] - The event target to dispatch download progress events to.
+   * @param {Object} _options - LanguageModel options.
+   * @param {Object} _sessionParams - Parameters for the cloud or local model.
+   * @param {EventTarget} [_monitorTarget] - The event target to dispatch download progress events to.
    * @returns {any} The created session object.
    */
-  createSession(options, sessionParams, monitorTarget) {
+  createSession(_options, _sessionParams, _monitorTarget) {
     throw new Error('Not implemented');
   }
 
   /**
    * Generates content (non-streaming).
-   * @param {Array} content - The history + new message content.
+   * @param {Array} _content - The history + new message content.
    * @returns {Promise<{text: string, usage: number}>}
    */
-  async generateContent(content) {
+  async generateContent(_content) {
     throw new Error('Not implemented');
   }
 
   /**
    * Generates content stream.
-   * @param {Array} content - The history + new content.
+   * @param {Array} _content - The history + new content.
    * @returns {Promise<AsyncIterable>} Stream of chunks.
    */
-  async generateContentStream(content) {
+  async generateContentStream(_content) {
     throw new Error('Not implemented');
   }
 
   /**
    * Counts tokens.
-   * @param {Array} content - The content to count.
+   * @param {Array} _content - The content to count.
    * @returns {Promise<number>} Total tokens.
    */
-  async countTokens(content) {
+  async countTokens(_content) {
     throw new Error('Not implemented');
   }
 }

prompt-api-polyfill/backends/firebase.js

@@ -23,7 +23,6 @@ import { DEFAULT_MODELS } from './defaults.js';
  */
 export default class FirebaseBackend extends PolyfillBackend {
   #model;
-  #sessionParams;
 
   constructor(config) {
     const {
@@ -52,26 +51,46 @@ export default class FirebaseBackend extends PolyfillBackend {
     });
   }
 
+  /**
+   * Creates a model session and stores it.
+   * @param {Object} _options - LanguageModel options.
+   * @param {Object} sessionParams - Parameters for the cloud or local model.
+   * @returns {any} The created session object.
+   */
   createSession(_options, sessionParams) {
-    this.#sessionParams = sessionParams;
     this.#model = getGenerativeModel(this.ai, {
       mode: InferenceMode.ONLY_IN_CLOUD,
       inCloudParams: sessionParams,
     });
     return this.#model;
   }
 
+  /**
+   * Generates content (non-streaming).
+   * @param {Array} contents - The history + new message content.
+   * @returns {Promise<{text: string, usage: number}>}
+   */
   async generateContent(contents) {
     const result = await this.#model.generateContent({ contents });
     const usage = result.response.usageMetadata?.promptTokenCount || 0;
     return { text: result.response.text(), usage };
   }
 
+  /**
+   * Generates content stream.
+   * @param {Array} contents - The history + new content.
+   * @returns {Promise<AsyncIterable>} Stream of chunks.
+   */
   async generateContentStream(contents) {
     const result = await this.#model.generateContentStream({ contents });
     return result.stream;
   }
 
+  /**
+   * Counts tokens.
+   * @param {Array} contents - The content to count.
+   * @returns {Promise<number>} Total tokens.
+   */
   async countTokens(contents) {
     const { totalTokens } = await this.#model.countTokens({
       contents,

prompt-api-polyfill/backends/gemini.js

@@ -20,12 +20,23 @@ export default class GeminiBackend extends PolyfillBackend {
     this.#ai = new GoogleGenAI({ apiKey: config.apiKey });
   }
 
+  /**
+   * Creates a model session.
+   * @param {Object} options - LanguageModel options.
+   * @param {Object} sessionParams - Session parameters.
+   * @returns {Object} The session object.
+   */
   createSession(options, sessionParams) {
     this.#sessionParams = sessionParams;
     this.#modelName = options.modelName || this.modelName;
     return { model: this.#modelName, params: sessionParams };
   }
 
+  /**
+   * Generates content (non-streaming).
+   * @param {Array} contents - The history + new message content.
+   * @returns {Promise<{text: string, usage: number}>}
+   */
   async generateContent(contents) {
     const config = {
       systemInstruction: this.#sessionParams.systemInstruction,
@@ -43,6 +54,11 @@ export default class GeminiBackend extends PolyfillBackend {
     return { text: response.text, usage };
   }
 
+  /**
+   * Generates content stream.
+   * @param {Array} contents - The history + new content.
+   * @returns {Promise<AsyncIterable>} Stream of chunks.
+   */
   async generateContentStream(contents) {
     const config = {
       systemInstruction: this.#sessionParams.systemInstruction,
@@ -69,6 +85,11 @@ export default class GeminiBackend extends PolyfillBackend {
     })();
   }
 
+  /**
+   * Counts tokens.
+   * @param {Array} contents - The content to count.
+   * @returns {Promise<number>} Total tokens.
+   */
   async countTokens(contents) {
     const { totalTokens } = await this.#ai.models.countTokens({
       model: this.#modelName,

prompt-api-polyfill/backends/openai.js

@@ -37,6 +37,12 @@ export default class OpenAIBackend extends PolyfillBackend {
     return 'available';
   }
 
+  /**
+   * Creates a model session and stores it.
+   * @param {Object} options - LanguageModel options.
+   * @param {Object} sessionParams - Parameters for the cloud or local model.
+   * @returns {any} The created session object.
+   */
   createSession(options, sessionParams) {
     // OpenAI doesn't have a "session" object like Gemini, so we return a context object
     // tailored for our generate methods.
@@ -155,6 +161,11 @@ export default class OpenAIBackend extends PolyfillBackend {
     return hasAudio ? `${this.modelName}-audio-preview` : this.modelName;
   }
 
+  /**
+   * Generates content (non-streaming).
+   * @param {Array} contents - The history + new message content.
+   * @returns {Promise<{text: string, usage: number}>}
+   */
   async generateContent(contents) {
     const { messages } = this.#convertContentsToInput(
       contents,
@@ -212,6 +223,11 @@ export default class OpenAIBackend extends PolyfillBackend {
     }
   }
 
+  /**
+   * Generates content stream.
+   * @param {Array} contents - The history + new content.
+   * @returns {Promise<AsyncIterable>} Stream of chunks.
+   */
   async generateContentStream(contents) {
     const { messages } = this.#convertContentsToInput(
       contents,
@@ -249,7 +265,6 @@ export default class OpenAIBackend extends PolyfillBackend {
 
       // Convert OpenAI stream to an AsyncIterable that yields chunks
       return (async function* () {
-        let firstChunk = true;
         for await (const chunk of stream) {
           let text = chunk.choices[0]?.delta?.content;
           if (text) {
@@ -268,6 +283,11 @@ export default class OpenAIBackend extends PolyfillBackend {
     }
   }
 
+  /**
+   * Counts tokens.
+   * @param {Array} contents - The content to count.
+   * @returns {Promise<number>} Total tokens.
+   */
   async countTokens(contents) {
     // OpenAI does not provide a public API endpoint for counting tokens before generation.
     // Implementing countTokens strictly requires a tokenizer like `tiktoken`.