干货教程

1、服务端采用 SSE 返回数据

视频教程

随着 Ai 大模型流行，大模型的生成时间会很长，这时候我们可以采用 SSE 的方式返回数据，这样可以让用户看到生成的进度，下面是一个简单的例子：

服务端

import { CoolController, BaseController } from "@cool-midway/core";
import { Get, Inject } from "@midwayjs/core";
import { Context } from "koa";
import { PluginService } from "../../../plugin/service/info";
import { PassThrough } from "stream";

/**
 * 事件流 服务端主动推送
 */
@CoolController()
export class OpenDemoSSEController extends BaseController {
	@Inject()
	ctx: Context;

	@Inject()
	pluginService: PluginService;

	@Get("/call", { summary: "事件流 服务端主动推送" })
	async call() {
		// 设置响应头
		this.ctx.set("Content-Type", "text/event-stream");
		this.ctx.set("Cache-Control", "no-cache");
		this.ctx.set("Connection", "keep-alive");

		const stream = new PassThrough();

		// 发送数据
		const send = (data: any) => {
			stream.write(`data: ${JSON.stringify(data)}\n\n`);
		};

		// 获取插件实例
		const instance = await this.pluginService.getInstance("ollama");
		// 调用chat
		const messages = [
			{ role: "system", content: "你叫小酷，是个编程助手" },
			{ role: "user", content: "用js写个Hello World" }
		];
		instance.chat(messages, { stream: true }, (res) => {
			send(res);
			if (res.isEnd) {
				this.ctx.res.end();
			}
		});

		this.ctx.status = 200;
		this.ctx.body = stream;
	}
}

客户端

const axios = require("axios");

const url = "http://127.0.0.1:8001/open/demo/sse/call";

const eventSource = axios.get(url, {
	responseType: "stream"
});

eventSource.then((response) => {
	// 收到消息
	response.data.on("data", (event) => {
		console.log("Message received:", event.toString());
	});
	// 发送结束
	response.data.on("end", () => {
		console.log("Connection closed");
	});
});