In my Angular 16 (standalone) app, I have a simple service to test LangChain against OpenAI.
This same code is working perfectly fine in a NodeJS app, however, when run from Angular, the result returned from OpenAI is always an empty string:

在我的Angel 16(独立的)应用程序中，我有一个简单的服务来测试LangChain和OpenAI。同样的代码在NodeJS应用程序中运行得非常好，然而，当从角度运行时，OpenAI返回的结果总是空字符串：

[llm/start] [1:llm:OpenAIChat] Entering LLM run with input: {
  "prompts": [
    "Israel's capital is"
  ]
}
console.js:132 [llm/end] [1:llm:OpenAIChat] [12ms] Exiting LLM run with output: {
  "generations": [
    [
      {
        "text": ""
      }
    ]
  ]
}
chat.service.ts:49 Completion returned in simplePromptTest: 

Here is the Angular service code generating the above output:

以下是生成上述输出的角度服务代码：

import { OpenAI } from "langchain/llms/openai";

const llm = new OpenAI({
  openAIApiKey: "sk-......ws",
  modelName: "gpt-3.5-turbo",
  temperature: 0,
  verbose: true
});

@Injectable({
  providedIn: 'root'
})
export class ChatService {

  constructor() { }

  async simplePromptTest() {
    const result = await llm.predict("Israel's capital is");
    console.log('Completion returned in simplePromptTest: ', result);
    return result;
  }
}

Packages I installed are:

我安装的程序包包括：

  npm install -S langchain
  npm install -S openai

What am I missing, please?

我错过了什么？