Android: org.apache.http.NoHttpResponseException: 目标服务器响应失败

Question

我的 Android 应用程序使用 HttpClient/HttpGet 来访问 REST API。我还设置了:

httpGet.addHeader("Authorization", "Basic " + basicAuth);

... 将 Base64 编码的“用户名:密码”发送到服务器。为了测试，我只使用 HTTP 而不是 HTTPS 连接到服务器。

每当我在 HttpClient 上调用“执行”时，我都会收到以下异常:

07-28 10:51:39.610: I/# PA #(12112): org.apache.http.NoHttpResponseException: The target server failed to respond
07-28 10:51:39.610: I/# PA #(12112):    at org.apache.http.impl.conn.DefaultResponseParser.parseHead(DefaultResponseParser.java:85)
07-28 10:51:39.610: I/# PA #(12112):    at org.apache.http.impl.io.AbstractMessageParser.parse(AbstractMessageParser.java:174)
07-28 10:51:39.610: I/# PA #(12112):    at org.apache.http.impl.AbstractHttpClientConnection.receiveResponseHeader(AbstractHttpClientConnection.java:180)
07-28 10:51:39.610: I/# PA #(12112):    at org.apache.http.impl.conn.DefaultClientConnection.receiveResponseHeader(DefaultClientConnection.java:235)
07-28 10:51:39.610: I/# PA #(12112):    at org.apache.http.impl.conn.AbstractClientConnAdapter.receiveResponseHeader(AbstractClientConnAdapter.java:259)
07-28 10:51:39.610: I/# PA #(12112):    at org.apache.http.protocol.HttpRequestExecutor.doReceiveResponse(HttpRequestExecutor.java:279)
07-28 10:51:39.610: I/# PA #(12112):    at org.apache.http.protocol.HttpRequestExecutor.execute(HttpRequestExecutor.java:121)
07-28 10:51:39.610: I/# PA #(12112):    at org.apache.http.impl.client.DefaultRequestDirector.execute(DefaultRequestDirector.java:428)
07-28 10:51:39.610: I/# PA #(12112):    at org.apache.http.impl.client.AbstractHttpClient.execute(AbstractHttpClient.java:555)
07-28 10:51:39.610: I/# PA #(12112):    at org.apache.http.impl.client.AbstractHttpClient.execute(AbstractHttpClient.java:487)
07-28 10:51:39.610: I/# PA #(12112):    at org.apache.http.impl.client.AbstractHttpClient.execute(AbstractHttpClient.java:465)
07-28 10:51:39.610: I/# PA #(12112):    at org.thomasamsler.android.app.tasks.HttpGetTask.doInBackground(HttpGetTask.java:87)
07-28 10:51:39.610: I/# PA #(12112):    at org.foo.android.app.tasks.HttpGetTask.doInBackground(HttpGetTask.java:1)
07-28 10:51:39.610: I/# PA #(12112):    at android.os.AsyncTask$2.call(AsyncTask.java:264)
07-28 10:51:39.610: I/# PA #(12112):    at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:305)
07-28 10:51:39.610: I/# PA #(12112):    at java.util.concurrent.FutureTask.run(FutureTask.java:137)
07-28 10:51:39.610: I/# PA #(12112):    at android.os.AsyncTask$SerialExecutor$1.run(AsyncTask.java:208)
07-28 10:51:39.610: I/# PA #(12112):    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1076)
07-28 10:51:39.610: I/# PA #(12112):    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:569)
07-28 10:51:39.610: I/# PA #(12112):    at java.lang.Thread.run(Thread.java:856)

注意:

我实际上有三台开发服务器，它们分别来自不同的托管服务提供商。当连接到其中两个时，出现上述错误。连接到第三台服务器时，一切正常。此外，其他 GET 和 POST 请求在所有三个开发服务器上都可以正常工作。

所以我想知道在设置基本身份验证 header 时是否有关于 HTTP GET 的特定内容。

我也可以使用“curl”调用有问题的 REST API，没有任何问题。

代码:

import java.io.ByteArrayOutputStream;
import java.io.IOException;

import org.apache.http.HttpEntity;
import org.apache.http.HttpResponse;
import org.apache.http.client.ClientProtocolException;
import org.apache.http.client.HttpClient;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.impl.client.DefaultHttpClient;

import android.os.AsyncTask;
import android.util.Log;

public class HttpGetTask extends AsyncTask<HttpGetRequestArgs, Void, String> implements AppConstants {

    private HttpTaskNotifier mNotifier;

    private HttpResponse mHttpResponse;
    private int mHttpStatusCodeOk;
    private int mHttpStatusCode;
    private int mErrorCode = AppConstants.NO_ERROR;

    public HttpGetTask(int httpStatusCodeOk, HttpTaskNotifier notifier) {

        mNotifier = notifier;
        mHttpStatusCodeOk = httpStatusCodeOk;
    }

    @Override
    protected String doInBackground(HttpGetRequestArgs... args) {

        HttpGetRequestArgs httpGetRequestArgs = args[0];

        HttpClient httpClient = new DefaultHttpClient();
        HttpGet httpGet = null;

        try {

            httpGet = new HttpGet(httpGetRequestArgs.getUrl());

            String apiKey = httpGetRequestArgs.getApiKey();

            if (null != apiKey && !"".equals(apiKey)) {

                httpGet.addHeader("Authorization", "ApiKey " + apiKey);
            }

            String basicAuth = httpGetRequestArgs.getBasicAuth();

            if (null != basicAuth && !"".equals(basicAuth)) {

                httpGet.addHeader("Authorization", "Basic " + basicAuth);
            }

        }
        catch (IllegalArgumentException e) {

            Log.e(LOG_TAG, "EXCEPTION", e);
            return null;
        }

        try {

            mHttpResponse = httpClient.execute(httpGet);
        }
        catch (ClientProtocolException e) {

            mErrorCode = AppConstants.REST_ERROR;
            return null;
        }
        catch (IOException e) {

            mErrorCode = AppConstants.REST_ERROR;
            return null;
        }
        catch (IllegalArgumentException iae) {

            mErrorCode = AppConstants.REST_ERROR;
            return null;
        }

        if (null == mHttpResponse) {

            mErrorCode = AppConstants.REST_ERROR;
            return null;
        }

        mHttpStatusCode = mHttpResponse.getStatusLine().getStatusCode();

        if (mHttpStatusCodeOk != mHttpStatusCode) {

            mErrorCode = AppConstants.REST_ERROR;
            return null;
        }

        ByteArrayOutputStream out = new ByteArrayOutputStream();
        HttpEntity httpEntity = mHttpResponse.getEntity();

        if (null == httpEntity) {

            mErrorCode = AppConstants.REST_ERROR;
            return null;
        }

        try {

            httpEntity.writeTo(out);
            out.close();
        }
        catch (IOException ioe) {

            mErrorCode = AppConstants.REST_ERROR;
            return null;
        }

        return out.toString();
    }

    @Override
    protected void onPostExecute(String content) {

        if (AppConstants.NO_ERROR != mErrorCode) {

            mNotifier.onError(mErrorCode);
        }

        mNotifier.doProcess(content);
    }

    @Override
    protected void onCancelled() {

        mNotifier.doCancel();
    }
}

Answer 1

我终于明白问题出在哪里了。当我对用户名和密码进行 Base64 编码时，我对 Base64.encodeToString(...) 使用了错误的标志。所以我改变了错误:

来自:

basicAuth = Base64.encodeToString(basicAuth.getBytes(), Base64.DEFAULT);

收件人:

basicAuth = Base64.encodeToString(basicAuth.getBytes(), Base64.NO_WRAP);

...一切正常。