Android HttpUrlConnection:发布Multipart

Question

我正在尝试将测试文件发布到使用Android部署在tomcat上的spring rest servlet.我正在开发Android 4.1.2,但我已经在4.0.3上验证了同样的问题.

问题是文件上传需要很长时间(对于4MB文件大约需要70秒),也在本地网络中.使用3g连接可以节省时间.我已经排除它可能是服务器问题:使用curl执行相同的调用需要1/2秒,并且使用apache作为后端结果是相同的.

使用HttpClient工作正常.

我正在使用Spring Android RestClient 1.0.1.RELEASE,并且考虑到Android版本以及我没有覆盖默认行为的事实,它使用HttpUrlConnection而不是HttpClient来发出http请求.

我还实现了我的自定义ClientHttpRequestFactory,以便操纵SSL连接的一些细节,我已经定义了自己的ClientHttpRequestInterceptor实现,以便修改身份验证头.

我也设置setBufferRequestBody(false)为了避免OutOfMemoryException大文件.但是这个属性对所需的时间没有影响.

MyClientHttpRequestFactory:

public class MyClientHttpRequestFactory extends SimpleClientHttpRequestFactory{

    @Override
    protected void prepareConnection(HttpURLConnection connection,  String httpMethod) throws IOException {
        super.prepareConnection(connection, httpMethod);
        connection.setConnectTimeout(240 * 1000);
        connection.setReadTimeout(240 * 1000);


        if ("post".equals(httpMethod.toLowerCase())) {
            setBufferRequestBody(false);
        }else {
            setBufferRequestBody(true);
        }
    }

@Override
protected HttpURLConnection openConnection(URL url, Proxy proxy) throws IOException {
    final HttpURLConnection httpUrlConnection = super.openConnection(url, proxy);

    if (url.getProtocol().toLowerCase().equals("https")
        &&
        settings.selfSignedCert().get())
    {
        try {
            ((HttpsURLConnection)httpUrlConnection).setSSLSocketFactory(getSSLSocketFactory());
            ((HttpsURLConnection)httpUrlConnection).setHostnameVerifier(new NullHostnameVerifier());
        } catch (Exception e) {
            MyLog.e(LOG_TAG, "OpenConnection", e);
        } 
    } 

    return httpUrlConnection;
}

MyClientHttpRequestInterceptor:

public class MyClientHttpRequestInterceptor implements ClientHttpRequestInterceptor {

    @Override
    public ClientHttpResponse intercept(HttpRequest request, byte[] body, ClientHttpRequestExecution execution) throws IOException {
        final HttpHeaders headers = request.getHeaders();

        headers.setAuthorization(new HttpBasicAuthentication( settings.username().get(), settings.password().get()));

        if (settings.enable_gzip().get()) {
            headers.setAcceptEncoding(ContentCodingType.GZIP);
        }

        return execution.execute(request, body);
    }
}

在这里我的休息电话:

List<ClientHttpRequestInterceptor> interceptors = Arrays.asList((ClientHttpRequestInterceptor)myClientHttpRequestInterceptor);

RestTemplate restTemplate = new RestTemplate();
restTemplate.getMessageConverters().add(new FormHttpMessageConverter());
restTemplate.getMessageConverters().add(new StringHttpMessageConverter());
restTemplate.getMessageConverters().add(new MappingJackson2HttpMessageConverter());
restTemplate.setInterceptors(interceptors);

MultiValueMap<String, Object> parts = new LinkedMultiValueMap<String, Object>();
parts.add("file", new FileSystemResource("/sdcard/test/4MB_file"));

HttpEntity<MultiValueMap> requestEntity = new HttpEntity<MultiValueMap>(parts);
restTemplate.exchange(myUrl, HttpMethod.POST, requestEntity, Integer.class).getBody();

}

看看Spring的Android源代码,我的请求传递的下一行代码是:

public ClientHttpRequest createRequest(URI uri, HttpMethod httpMethod) throws IOException {
    HttpURLConnection connection = openConnection(uri.toURL(), this.proxy);
    prepareConnection(connection, httpMethod.name());
    if (this.bufferRequestBody) {
        return new SimpleBufferingClientHttpRequest(connection);
    } else {
        return new SimpleStreamingClientHttpRequest(connection, this.chunkSize);
    }
}

因为this.bufferRequestBody是false,return new SimpleStreamingClientHttpRequest(connection, this.chunkSize);被执行(用chunkSize = 0)

SimpleStreamingClientHttpRequest(HttpURLConnection connection, int chunkSize) {
    this.connection = connection;
    this.chunkSize = chunkSize;

    // Bugs with reusing connections in Android versions older than Froyo (2.2)
    if (olderThanFroyo) {
        System.setProperty("http.keepAlive", "false");
    }
}

然后:

ClientHttpRequest delegate = requestFactory.createRequest(request.getURI(), request.getMethod());

delegate.getHeaders().putAll(request.getHeaders());

if (body.length > 0) {
    FileCopyUtils.copy(body, delegate.getBody());
}
return delegate.execute();

从这里我认为所有的android子系统..

我已经转储了tcp流量并进行了分析:

POST /urlWherePost HTTP/1.1
Content-Type: multipart/form-data;boundary=nKwsP85ZyyzSDuAqozCTuZOSxwF1jLAtd0FECUPF
Authorization: Basic xxxxxxxxxxxxxxxxxxxxxxxxxx=
Accept-Encoding: gzip
User-Agent: Dalvik/1.6.0 (Linux; U; Android 4.1.2; sdk Build/MASTER)
Host: 192.168.168.225:8080
Connection: Keep-Alive
Content-Length: 4096225

--nKwsP85ZyyzSDuAqozCTuZOSxwF1jLAtd0FECUPF
Content-Disposition: form-data; name="file"; filename="4MB_file"
Content-Type: application/octet-stream
Content-Length: 4096000

我试着用curl重新创建类似的请求:

curl --verbose 
    -H "Connection: Keep-Alive" 
    -H "Content-Type: multipart/form-data" 
    -H "Accept-Encoding: gzip" 
    -H "Content-Disposition: form-data; name=\"file\"; filename=\"4MB_file\"" 
    -H "Content-Type: application/octet-stream" 
    --user xxx:xxx 
    -X POST 
    --form file=@4MB_file 
    http://192.168.168.225:8080/urlWherePost

但随着卷曲,帖子还可以.

发布json数据不是问题(可能是小体型).但是当我尝试发送"大"文件时,时间会增加.

查看DDMS shell,在网络统计上,我还发现TX的网络吞吐量从未超过250kb.似乎有一个bootleneck,但如何调查呢？在哪里可以查看,我可以更改哪个参数？

谢谢你的任何建议!

Answer 1

您是否尝试过使用 MultipartEntity 方法？当我从服务器下载大量 JSON 数据时遇到了同样的问题，但我切换到这种方法并捕获了服务器提供给我的所有数据。

HttpClient httpclient = new DefaultHttpClient();
HttpPost httppost = new HttpPost("http://myurl.com");

try {
    MultipartEntity entity = new MultipartEntity();

    entity.addPart("type", new StringBody("json"));
    entity.addPart("data", new JSONObject(data));
    httppost.setEntity(entity);
    HttpResponse response = httpclient.execute(httppost);
} catch (ClientProtocolException e) {
} catch (IOException e) {
} catch (JSONException e){
}