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使用inputStreamResponseListener使用Jetty HTTP客户端复制inputStream块

jetty java

Martin · 技术社区 · 6 年前

我正在使用Jetty9.4.8HTTP客户机,希望将传入数据流写入文件。目前我正在使用一个inputstreamResponseListener和ioutils.copy(..)写入一个fileoutputstream。我还尝试了files.copy()。

InputStreamResponseListener streamResponseListener = new InputStreamResponseListener();

request.send(streamResponseListener);

if(streamResponseListener.get(5, TimeUnit.MINUTES).getStatus() == 200) {
    OutputStream outputStream = null;
    try {
        TMP_FILE.toFile().createNewFile();
        outputStream = new FileOutputStream(TMP_FILE.toFile());
        IOUtils.copy(inputStream, outputStream);
    } catch(IOException e) {
        this.getLogService().log(..)
    } finally {
        IOUtils.closeQuietly(inputStream);
        IOUtils.closeQuietly(outputStream);
    }

    // NOT REACHED IN CASE InputStream is BLOCKED FOR SOME REASON
}

但是,复制方法似乎在收到所有字节后被阻塞。为什么会发生这种情况?我怎样才能避免这种情况?

请求的HTTP内容的头:

Date: Wed, 23 May 2018 16:46:06 GMT
Content-Type: application/octet-stream
Content-Disposition: attachment; filename=".."
Content-Length: 613970044
Server: Jetty(9.4.8.v20171121)

来自Apache Commons IO 2.4版的ioutils

1 回复 | 直到 6 年前

Joakim Erdfelt 6 年前

这是你的代码库的一个工作示例,只使用Java和JETTY。

这是从已知符合HTTP规范的服务器请求内容。

package demo.jettyclient;

import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.net.URI;
import java.net.URL;
import java.nio.file.Files;
import java.nio.file.Path;
import java.util.Properties;
import java.util.concurrent.TimeUnit;

import org.eclipse.jetty.client.HttpClient;
import org.eclipse.jetty.client.api.Request;
import org.eclipse.jetty.client.api.Response;
import org.eclipse.jetty.client.util.InputStreamResponseListener;
import org.eclipse.jetty.http.HttpStatus;
import org.eclipse.jetty.util.IO;
import org.eclipse.jetty.util.StringUtil;
import org.eclipse.jetty.util.ssl.SslContextFactory;

public class DownloadUrl
{
    public static void main(String[] args) throws Exception
    {
        String uriString = "https://upload.wikimedia.org/wikipedia/en/a/a1/Jetty_logo.png?download";

        if (args.length >= 1)
            uriString = args[0];

        URI srcUri = URI.create(uriString);

        SslContextFactory ssl = new SslContextFactory(true);

        HttpClient client = new HttpClient(ssl);
        try
        {
            client.start();

            Request request = client.newRequest(srcUri);

            System.out.printf("Using HttpClient v%s%n", getHttpClientVersion());
            System.out.printf("Requesting: %s%n", srcUri);
            InputStreamResponseListener streamResponseListener = new InputStreamResponseListener();
            request.send(streamResponseListener);
            Response response = streamResponseListener.get(5, TimeUnit.SECONDS);

            if (response.getStatus() != HttpStatus.OK_200)
            {
                throw new IOException(
                        String.format("Failed to GET URI [%d %s]: %s",
                                response.getStatus(),
                                response.getReason(),
                                srcUri));
            }

            Path tmpFile = Files.createTempFile("tmp", ".dl");

            try (InputStream inputStream = streamResponseListener.getInputStream();
                 OutputStream outputStream = Files.newOutputStream(tmpFile))
            {
                IO.copy(inputStream, outputStream);
            }

            System.out.printf("Downloaded %s%n", srcUri);
            System.out.printf("Destination: %s (%,d bytes)%n", tmpFile.toString(), Files.size(tmpFile));
        }
        finally
        {
            client.stop();
        }
    }

    private static String getHttpClientVersion()
    {
        ClassLoader cl = HttpClient.class.getClassLoader();

        // Attempt to use maven pom properties first
        String pomResource = "/META-INF/maven/org/eclipse/jetty/jetty-client/pom.properties";
        URL url = cl.getResource(pomResource);
        if (url != null)
        {
            try (InputStream in = url.openStream())
            {
                Properties props = new Properties();
                props.load(in);
                String version = props.getProperty("version");
                if (StringUtil.isNotBlank(version))
                    return version;
            }
            catch (IOException ignore)
            {
            }
        }

        // Attempt to use META-INF/MANIFEST.MF
        String version = HttpClient.class.getPackage().getImplementationVersion();
        if (StringUtil.isNotBlank(version))
            return version;

        return "<unknown>";
    }
}

当运行时,这会导致…

2018-05-23 10:52:08.401:INFO::main: Logging initialized @325ms to org.eclipse.jetty.util.log.StdErrLog
Using HttpClient v9.4.9.v20180320
Requesting: https://upload.wikimedia.org/wikipedia/en/a/a1/Jetty_logo.png?download
Downloaded https://upload.wikimedia.org/wikipedia/en/a/a1/Jetty_logo.png?download
Destination: C:\Users\joakim\AppData\Local\Temp\tmp2166600286896937563.dl (11,604 bytes)

Process finished with exit code 0

以下一个(或多个)可能导致您的问题。

服务器有问题,不符合HTTP规范。
HTTP交换还没有完成(从协议的角度来看)。捕获流量并验证行为。
您正在使用的ioutil库(您没有说是哪个库)有一个bug。

wget(或curl)工作的事实很可能是因为它们对内容长度不严格(根据RFC7230中的建议),并且将显示/下载接收到的所有内容,直到物理连接断开/断开。虽然HTTP/1.1协议具有连接持久性,并且在请求(和响应)内容结束时有严格的规则。