Android: org.apache.http.NoHttpResponseException: The target server failed to respond
<p>My Android app uses an HttpClient/HttpGet to access a REST API. I also set:</p>

<pre><code>httpGet.addHeader("Authorization", "Basic " + basicAuth);
</code></pre>

<p>... which sends the Base64 encoded "username:password" to the server. For testing, I just use HTTP and not HTTPS to connect to the server.</p>

<p>Whenever I call "execute" on the HttpClient, I receive the following exception:</p>

<pre><code>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)
</code></pre>

<p>NOTE:</p>

<p>I actually have three development servers with different hosting providers. When connecting to two of them, I get the above error. When connecting to the third server, everything works fine. Also, other GET and POST request work just fine on all three development servers.</p>

<p>So I am wondering if there is something specific about HTTP GET when setting the basic auth header.</p>

<p>I can also make a call using "curl" to the REST API in question without any issues.</p>

<p>Code:</p>

<pre><code>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&lt;HttpGetRequestArgs, Void, String&gt; 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 &amp;&amp; !"".equals(apiKey)) {

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

            String basicAuth = httpGetRequestArgs.getBasicAuth();

            if (null != basicAuth &amp;&amp; !"".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();
    }
}
</code></pre>
