@langchain/community/dist/chat_models/tests/chatgooglevertexai.int.test.js

Third-party integrations for LangChain.js

import { describe, expect, test } from "@jest/globals";
import { ChatMessage, HumanMessage } from "@langchain/core/messages";
import { PromptTemplate, ChatPromptTemplate, AIMessagePromptTemplate, HumanMessagePromptTemplate, SystemMessagePromptTemplate, } from "@langchain/core/prompts";
import { ChatGoogleVertexAI } from "../googlevertexai/index.js";
describe("ChatGoogleVertexAI", () => {
    test("call", async () => {
        const chat = new ChatGoogleVertexAI();
        const message = new HumanMessage("Hello!");
        const res = await chat.invoke([message]);
        console.log({ res });
    });
    test("32k", async () => {
        const chat = new ChatGoogleVertexAI({
            model: "chat-bison-32k",
        });
        const message = new HumanMessage("Hello!");
        const res = await chat.invoke([message]);
        console.log({ res });
    });
    test("generate", async () => {
        const chat = new ChatGoogleVertexAI();
        const message = new HumanMessage("Hello!");
        const res = await chat.generate([[message]]);
        console.log(JSON.stringify(res, null, 2));
    });
    test("custom messages", async () => {
        const chat = new ChatGoogleVertexAI();
        const res = await chat.invoke([new ChatMessage("Hello!", "user")]);
        console.log(JSON.stringify(res, null, 2));
    });
    test("prompt templates", async () => {
        const chat = new ChatGoogleVertexAI();
        // PaLM doesn't support translation yet
        const systemPrompt = PromptTemplate.fromTemplate("You are a helpful assistant who must always respond like a {job}.");
        const chatPrompt = ChatPromptTemplate.fromMessages([
            new SystemMessagePromptTemplate(systemPrompt),
            HumanMessagePromptTemplate.fromTemplate("{text}"),
        ]);
        const responseA = await chat.generatePrompt([
            await chatPrompt.formatPromptValue({
                job: "pirate",
                text: "What would be a good company name a company that makes colorful socks?",
            }),
        ]);
        console.log(responseA.generations);
    });
    test("longer chain of messages", async () => {
        const chat = new ChatGoogleVertexAI();
        const chatPrompt = ChatPromptTemplate.fromMessages([
            HumanMessagePromptTemplate.fromTemplate(`Hi, my name is Joe!`),
            AIMessagePromptTemplate.fromTemplate(`Nice to meet you, Joe!`),
            HumanMessagePromptTemplate.fromTemplate("{text}"),
        ]);
        const responseA = await chat.generatePrompt([
            await chatPrompt.formatPromptValue({
                text: "What did I just say my name was?",
            }),
        ]);
        console.log(responseA.generations);
    });
    test("code, chain of messages", async () => {
        const chat = new ChatGoogleVertexAI({ model: "codechat-bison" });
        const chatPrompt = ChatPromptTemplate.fromMessages([
            SystemMessagePromptTemplate.fromTemplate(`Answer all questions using Python and just show the code without an explanation.`),
            HumanMessagePromptTemplate.fromTemplate("{text}"),
        ]);
        const responseA = await chat.generatePrompt([
            await chatPrompt.formatPromptValue({
                text: "How can I write a for loop counting to 10?",
            }),
        ]);
        console.log(JSON.stringify(responseA.generations, null, 1));
    });
    test("stream method", async () => {
        const model = new ChatGoogleVertexAI();
        const stream = await model.stream("What is the answer to life, the universe, and everything? Be verbose.");
        const chunks = [];
        for await (const chunk of stream) {
            console.log("chunk", chunk);
            chunks.push(chunk);
        }
        expect(chunks.length).toBeGreaterThan(1);
    });
});