开源模型应用落地-业务整合篇（一）

一、前言

    经过对qwen-7b-chat的部署以及与vllm的推理加速的整合，我们成功构建了一套高性能、高可靠、高安全的AI服务能力。现在，我们将着手整合具体的业务场景，以实现完整可落地的功能交付。

    作为上游部门，通常会采用最常用的方式来接入下游服务。为了调用我们的AI服务，我们将使用Java语言，并分别使用HttpClient、OkHttp等工具来实现调用。这样可以确保我们能够高效地与AI服务进行交互。

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二、术语

2.1.OkHttp

    是一个开源的Java和Kotlin HTTP客户端库，用于进行网络请求。OkHttp支持HTTP/1.1和HTTP/2协议，具有连接池、请求重试、缓存、拦截器等功能。它还提供了异步和同步请求的支持，并且可以与各种平台和框架无缝集成，是Android开发中常用的网络请求库之一。通过使用OkHttp，开发人员可以轻松地发送HTTP请求、处理响应以及管理网络连接，从而加快应用程序的网络通信速度和效率。

2.2.HttpClient

    是一个用于发送HTTP请求和接收HTTP响应的开源库。它提供了一种方便的方式来与Web服务器进行通信，并执行各种HTTP操作，例如发送GET请求、POST请求等。HttpClient库通常用于编写客户端应用程序或服务，这些应用程序需要与Web服务器或Web API进行通信。它提供了许多功能，包括连接管理、身份验证、请求和响应拦截、Cookie管理等。

2.3.HttpURLConnection

    是Java提供的一个用于发送HTTP请求和接收HTTP响应的类。它是Java标准库中的一部分，用于与Web服务器进行通信。HttpURLConnection类提供了一组方法，使您能够创建HTTP连接、设置请求方法（如GET、POST等）、设置请求头、设置请求体和其他参数，并发送请求到指定的URL。它还提供了方法来获取HTTP响应的状态码、响应头和响应体等信息。

    OkHttp和HttpClient提供了更丰富的功能和更好的性能，适用于大多数情况下。HttpURLConnection是Java标准库中的类，提供了基本的HTTP功能

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三、前置条件

3.1. 完成Qwen-7b-Chat（Qwen-1_8B-Chat）模型的本地部署或服务端部署

    参见“开源模型应用落地-qwen-7b-chat与vllm实现推理加速的正确姿势”系列文章

3.2. 完成对外服务接口的封装，屏蔽不同模型的调用差异

    参见“开源模型应用落地-qwen-7b-chat与vllm实现推理加速的正确姿势”系列文章

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四、技术实现

4.1. HttpURLConnection

import lombok.extern.slf4j.Slf4j;
import java.io.ByteArrayOutputStream;
import java.io.InputStream;
import java.io.OutputStream;
import java.net.HttpURLConnection;
import java.net.URL;
import java.nio.charset.StandardCharsets;
import java.util.Objects;

@Slf4j
public class QWenCallTest {

    private static String url = "http://127.0.0.1:9999/api/chat";
    private static String DEFAULT_TEMPLATE = "{\"prompt\":\"%s\",\"history\":%x,\"top_p\":0.9, \"temperature\":0.45,\"repetition_penalty\":1.1, \"max_new_tokens\":8192}";
    private static String DEFAULT_USERID = "xxxxx";
    private static String DEFAULT_SECRET = "xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx";
    private static int DEFAULT_CONNECTION_TIMEOUT = 3 * 1000;
    private static int DEFAULT_READ_TIMEOUT = 30 * 1000;

    public static void main(String[] args) {
        String question = "我家周边有什么好吃、好玩的地方嘛？";
        String history = "[{\n" +
                "\"from\": \"user\",\n" +
                "\"value\": \"你好\"\n" +
                "},\n" +
                "{\n" +
                "\"from\": \"assistant\",\n" +
                "\"value\": \"你好！有什么我能为你效劳的吗？\"\n" +
                "},\n" +
                "{\n" +
                "\"from\": \"user\",\n" +
                "\"value\": \"我家在广州，你呢?\"\n" +
                "},\n" +
                "{\n" +
                "\"from\": \"assistant\",\n" +
                "\"value\": \"我是一个人工智能助手，没有具体的家。\"\n" +
                "}]";

        String prompt = DEFAULT_TEMPLATE.replace("%s", question).replace("%x", history);
        log.info("prompt: {}", prompt);

        HttpURLConnection conn = null;
        OutputStream os = null;
        try {
            //1.设置URL
            URL urlObject = new URL(url);
            //2.打开URL连接
            conn = (HttpURLConnection) urlObject.openConnection();
            //3.设置请求方式
            conn.setRequestMethod("POST");
            conn.setRequestProperty("Content-Type", "application/json;charset=utf-8");
            conn.setRequestProperty("Accept", "text/event-stream");
            conn.setRequestProperty("userId", DEFAULT_USERID);
            conn.setRequestProperty("secret", DEFAULT_SECRET);
            conn.setDoOutput(true);
            conn.setDoInput(true);

            // 设置连接超时时间为60秒
            conn.setConnectTimeout(DEFAULT_CONNECTION_TIMEOUT);

            // 设置读取超时时间为60秒
            conn.setReadTimeout(DEFAULT_READ_TIMEOUT);


            os = conn.getOutputStream();
            os.write(prompt.getBytes("utf-8"));

        } catch (Exception e) {
            log.error("请求模型接口异常", e);
        } finally {
            if(!Objects.isNull(os)){
                try {
                    os.flush();
                    os.close();
                } catch (Exception e) {
                }

            }
        }

        InputStream is = null;
        try{
            if(!Objects.isNull(conn)){
                int responseCode = conn.getResponseCode();
                log.info("Response Code: " + responseCode);

                if(responseCode == 200){
                    is = conn.getInputStream();
                }else{
                    is = conn.getErrorStream();
                }

                byte[] bytes = new byte[1024];
                int len = 0;

                while ((len = is.read(bytes)) != -1) {
                    ByteArrayOutputStream outputStream = new ByteArrayOutputStream();
                    outputStream.write(bytes, 0, len);
                    String response = new String(outputStream.toByteArray(), StandardCharsets.UTF_8);
                    log.info(response);
                }
            }

        } catch (Exception e) {
            log.error("请求模型接口异常", e);
        } finally {
            if (!Objects.isNull(is)) {
                try {
                    is.close();
                } catch (Exception e) {
                    e.printStackTrace();
                }
            }

        }

    }

}

4.2. OkHttp

import com.alibaba.fastjson.JSON;
import lombok.extern.slf4j.Slf4j;
import okhttp3.*;
import java.io.ByteArrayOutputStream;
import java.io.InputStream;
import java.nio.charset.StandardCharsets;
import java.util.Objects;
import java.util.concurrent.CountDownLatch;
import java.util.concurrent.TimeUnit;

@Slf4j
public class QWenCallTest {
    private static String url = "http://127.0.0.1:9999/api/chat";
    private static String DEFAULT_TEMPLATE = "{\"prompt\":\"%s\",\"history\":%x,\"top_p\":0.9, \"temperature\":0.45,\"repetition_penalty\":1.2, \"max_new_tokens\":8192}";
    private static long DEFAULT_CONNECTION_TIMEOUT = 3 * 1000;
    private static long DEFAULT_WRITE_TIMEOUT = 15 * 1000;
    private static long DEFAULT_READ_TIMEOUT = 15 * 1000;
    
    private final static Request.Builder buildHeader(Request.Builder builder) {
        return builder
                .addHeader("Content-Type", "application/json; charset=utf-8")
                .addHeader("userId", "xxxxx")
                .addHeader("secret", "xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx");
    }

    private final static Request buildRequest(String prompt) {
        //创建一个请求体对象(body)
        MediaType mediaType = MediaType.parse("application/json");
        RequestBody requestBody = RequestBody.create(mediaType,prompt);

        return buildHeader(new Request.Builder().post(requestBody))
                .url(url).build();
    }

    

    public static void chat(String question,String history,CountDownLatch countDownLatch) {
        //定义请求的参数
        String prompt = DEFAULT_TEMPLATE.replace("%s", question).replace("%x", history);
        log.info("prompt: {}", prompt);

        //创建一个请求对象
        Request request = buildRequest(prompt);

        //发送请求:创建了一个请求工具对象，调用执行request对象
        OkHttpClient okHttpClient = new OkHttpClient().newBuilder()
                .connectTimeout(DEFAULT_CONNECTION_TIMEOUT, TimeUnit.MILLISECONDS)
                .writeTimeout(DEFAULT_WRITE_TIMEOUT, TimeUnit.MILLISECONDS)
                .readTimeout(DEFAULT_READ_TIMEOUT, TimeUnit.MILLISECONDS)
                .build();

        InputStream is = null;
        try {
            Response response = okHttpClient.newCall(request).execute();
            //正常返回
            if(response.code() == 200){
                //打印返回的字符数据
                is = response.body().byteStream();
                byte[] bytes = new byte[1024];
                int len = 0;
                while ((len = is.read(bytes)) != -1) {
                    ByteArrayOutputStream outputStream = new ByteArrayOutputStream();
                    outputStream.write(bytes, 0, len);
                    outputStream.flush();

                    String result = new String(outputStream.toByteArray(), StandardCharsets.UTF_8);
                    log.info(result);
                }
            }
            else{
                String result = response.body().string();
                String jsonStr = JSON.parseObject(result).toJSONString();
                log.info(jsonStr);
            }


        } catch (Throwable e) {
            log.error("执行异常", e);
        } finally {
            if (!Objects.isNull(is)) {
                try {
                    is.close();
                } catch (Exception e) {
                    e.printStackTrace();
                }
            }

            countDownLatch.countDown();

        }

    }

    public static void main(String[] args) {
        CountDownLatch countDownLatch = new CountDownLatch(1);


        String question = "我家周边有什么好吃、好玩的地方嘛？";
        String history = "[{\n" +
                "\"from\": \"user\",\n" +
                "\"value\": \"你好\"\n" +
                "},\n" +
                "{\n" +
                "\"from\": \"assistant\",\n" +
                "\"value\": \"你好！有什么我能为你效劳的吗？\"\n" +
                "},\n" +
                "{\n" +
                "\"from\": \"user\",\n" +
                "\"value\": \"我家在广州，你呢?\"\n" +
                "},\n" +
                "{\n" +
                "\"from\": \"assistant\",\n" +
                "\"value\": \"我是一个人工智能助手，没有具体的家。\"\n" +
                "}]";



        //流式输出
        long starttime = System.currentTimeMillis();
        chat(question,history,countDownLatch);
        long endtime = System.currentTimeMillis();
        System.err.println((endtime-starttime));

        try {
            countDownLatch.await();
        } catch (InterruptedException e) {
            e.printStackTrace();
        }
    }


}

maven依赖

    com.squareup.okhttp3
    okhttp
    3.14.9

4.3. HttpClient

import lombok.extern.slf4j.Slf4j;
import org.asynchttpclient.AsyncHttpClient;
import org.asynchttpclient.AsyncHttpClientConfig;
import org.asynchttpclient.DefaultAsyncHttpClient;
import org.asynchttpclient.DefaultAsyncHttpClientConfig;
import org.asynchttpclient.channel.DefaultKeepAliveStrategy;
import java.io.IOException;
import java.util.concurrent.CountDownLatch;
import java.util.concurrent.TimeUnit;

@Slf4j
public class QwenCallTest {
    private static String url = "http://127.0.0.1:9999/api/chat";
    private static String DEFAULT_TEMPLATE = "{\"prompt\":\"%s\",\"history\":%x,\"top_p\":0.9, \"temperature\":0.45,\"repetition_penalty\":1.1, \"max_new_tokens\":8192}";
    private static int DEFAULT_CONNECTION_TIMEOUT = 3 * 1000;
    private static int DEFAULT_REQUEST_TIMEOUT = 15* 1000;
    private static int DEFAULT_READ_TIMEOUT = 15* 1000;

    private static String DEFAULT_USERID = "xxxxx";
    private static String DEFAULT_SECRET = "xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx";


    private static AsyncHttpClientConfig asyncHttpClientConfig = new DefaultAsyncHttpClientConfig.Builder()
            .setConnectTimeout(DEFAULT_CONNECTION_TIMEOUT)
            .setReadTimeout(DEFAULT_READ_TIMEOUT)
            .setRequestTimeout(DEFAULT_REQUEST_TIMEOUT)
            .setTcpNoDelay(true)
            .setMaxConnections(1_000_000)
            .setMaxConnectionsPerHost(100_000)
            .setMaxRequestRetry(0)
            .setSoReuseAddress(true)
            .setKeepAlive(true)
            .setKeepAliveStrategy(new DefaultKeepAliveStrategy())
            .build();

    public static final AsyncHttpClient ugc_asyncHttpClient = new DefaultAsyncHttpClient(asyncHttpClientConfig);


    public static void chat(String question,String history, CountDownLatch countDownLatch ) {
        String prompt = DEFAULT_TEMPLATE.replace("%s", question).replace("%x", history);
        log.info("prompt: {}", prompt);

        try {
            ugc_asyncHttpClient.preparePost(url)
                    .addHeader("Content-Type", "application/json; charset=utf-8")
                    .addHeader("userId", DEFAULT_USERID)
                    .addHeader("secret", DEFAULT_SECRET)
                    .addHeader("Accept", "text/event-stream")
                    .setBody(prompt)
                    .execute(new QwenStreamHandler(countDownLatch))
                    .get(30, TimeUnit.SECONDS);

        } catch (Exception e) {
            log.error(prompt + " >> 出现异常");
        }

    }


    public static void main(String[] args) {
        CountDownLatch countDownLatch = new CountDownLatch(1);
        String question = "我家周边有什么好吃、好玩的地方嘛？";
        String history = "[{\n" +
                "\"from\": \"user\",\n" +
                "\"value\": \"你好\"\n" +
                "},\n" +
                "{\n" +
                "\"from\": \"assistant\",\n" +
                "\"value\": \"你好！有什么我能为你效劳的吗？\"\n" +
                "},\n" +
                "{\n" +
                "\"from\": \"user\",\n" +
                "\"value\": \"我家在广州，你呢?\"\n" +
                "},\n" +
                "{\n" +
                "\"from\": \"assistant\",\n" +
                "\"value\": \"我是一个人工智能助手，没有具体的家。\"\n" +
                "}]";

        chat(question,history,countDownLatch);

        try {
            countDownLatch.await();
        } catch (InterruptedException e) {
            e.printStackTrace();
        }

        try {
            ugc_asyncHttpClient.close();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }


}

import io.netty.handler.codec.http.HttpHeaders;
import lombok.extern.slf4j.Slf4j;
import org.asynchttpclient.HttpResponseBodyPart;
import org.asynchttpclient.HttpResponseStatus;
import org.asynchttpclient.handler.StreamedAsyncHandler;
import org.asynchttpclient.netty.EagerResponseBodyPart;
import org.reactivestreams.Publisher;
import org.reactivestreams.Subscriber;
import org.reactivestreams.Subscription;

import java.util.concurrent.CountDownLatch;

@Slf4j
public class QwenStreamHandler implements StreamedAsyncHandler {
    private CountDownLatch countDownLatch;

    public QwenStreamHandler(CountDownLatch countDownLatch){
        this.countDownLatch = countDownLatch;
    }

    @Override
    public State onStream(Publisher publisher) {
        publisher.subscribe(new Subscriber() {
            @Override
            public void onSubscribe(Subscription subscription) {
                subscription.request(Long.MAX_VALUE);
            }

            @Override
            public void onNext(Object obj) {
                try{
                    if(obj instanceof EagerResponseBodyPart){
                        EagerResponseBodyPart part = (EagerResponseBodyPart)obj;
                        byte[] bytes = part.getBodyPartBytes();
                        String words = new String(bytes,"UTF-8");
                        log.info(words);
                    }
                }catch(Throwable e){
                    log.error("系统异常",e);
                }
            }

            @Override
            public void onError(Throwable throwable) {
                log.error("系统异常",throwable);
            }

            @Override
            public void onComplete() {
                countDownLatch.countDown();
 
            }
        });
        return State.CONTINUE;
    }

    @Override
    public State onStatusReceived(HttpResponseStatus responseStatus) throws Exception {
        log.info("onStatusReceived: {}",responseStatus.getStatusCode());
        return responseStatus.getStatusCode() == 200 ? State.CONTINUE : State.ABORT;
    }

    @Override
    public State onHeadersReceived(HttpHeaders headers) throws Exception {
        return State.CONTINUE;
    }

    @Override
    public State onBodyPartReceived(HttpResponseBodyPart bodyPart) throws Exception {
        return State.CONTINUE;
    }

    @Override
    public void onThrowable(Throwable t) {
        log.error("onThrowable", t);
    }

    @Override
    public String onCompleted() throws Exception {
        return State.ABORT.name();
    }
}

maven依赖

    org.apache.httpcomponents
    httpclient
    4.5.12



    org.asynchttpclient
    async-http-client
    2.12.3

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五、附带说明

5.1. 需要根据实际情况修改url，userId以及secret的信息

5.2. 如果AI服务已经实现了负载均衡，那么在URL中应该使用SLB（全局负载均衡）的IP地址