MyRedirectHandler.java

/*
    Android Asynchronous Http Client
    Copyright (c) 2014 Aymon Fournier <aymon.fournier@gmail.com>
    http://loopj.com

    Licensed under the Apache License, Version 2.0 (the "License");
    you may not use this file except in compliance with the License.
    You may obtain a copy of the License at

        http://www.apache.org/licenses/LICENSE-2.0

    Unless required by applicable law or agreed to in writing, software
    distributed under the License is distributed on an "AS IS" BASIS,
    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    See the License for the specific language governing permissions and
    limitations under the License.
*/

package com.smartandroid.sa.loopj;

import org.apache.http.Header;
import org.apache.http.HttpHost;
import org.apache.http.HttpRequest;
import org.apache.http.HttpResponse;
import org.apache.http.HttpStatus;
import org.apache.http.ProtocolException;
import org.apache.http.client.CircularRedirectException;
import org.apache.http.client.params.ClientPNames;
import org.apache.http.client.utils.URIUtils;
import org.apache.http.impl.client.DefaultRedirectHandler;
import org.apache.http.impl.client.RedirectLocations;
import org.apache.http.params.HttpParams;
import org.apache.http.protocol.ExecutionContext;
import org.apache.http.protocol.HttpContext;

import java.net.URI;
import java.net.URISyntaxException;

/**
 * Taken from StackOverflow
 *
 * @author Aymon Fournier, aymon.fournier@gmail.com
 * @see <a href="https://stackoverflow.com/questions/3420767/httpclient-redirecting-to-url-with-spaces-throwing-exception">https://stackoverflow.com/questions/3420767/httpclient-redirecting-to-url-with-spaces-throwing-exception</a>
 */
class MyRedirectHandler extends DefaultRedirectHandler {

    private static final String REDIRECT_LOCATIONS = "http.protocol.redirect-locations";
    private final boolean enableRedirects;

    public MyRedirectHandler(final boolean allowRedirects) {
        super();
        this.enableRedirects = allowRedirects;
    }

    @Override
    public boolean isRedirectRequested(
            final HttpResponse response,
            final HttpContext context) {
        if (!enableRedirects) {
            return false;
        }
        if (response == null) {
            throw new IllegalArgumentException("HTTP response may not be null");
        }
        int statusCode = response.getStatusLine().getStatusCode();
        switch (statusCode) {
            case HttpStatus.SC_MOVED_TEMPORARILY:
            case HttpStatus.SC_MOVED_PERMANENTLY:
            case HttpStatus.SC_SEE_OTHER:
            case HttpStatus.SC_TEMPORARY_REDIRECT:
                return true;
            default:
                return false;
        } //end of switch
    }

    @Override
    public URI getLocationURI(
            final HttpResponse response,
            final HttpContext context) throws ProtocolException {
        if (response == null) {
            throw new IllegalArgumentException("HTTP response may not be null");
        }
        //get the location header to find out where to redirect to
        Header locationHeader = response.getFirstHeader("location");
        if (locationHeader == null) {
            // got a redirect response, but no location header
            throw new ProtocolException(
                    "Received redirect response " + response.getStatusLine()
                            + " but no location header"
            );
        }
        //HERE IS THE MODIFIED LINE OF CODE
        String location = locationHeader.getValue().replaceAll(" ", "%20");

        URI uri;
        try {
            uri = new URI(location);
        } catch (URISyntaxException ex) {
            throw new ProtocolException("Invalid redirect URI: " + location, ex);
        }

        HttpParams params = response.getParams();
        // rfc2616 demands the location value be a complete URI
        // Location       = "Location" ":" absoluteURI
        if (!uri.isAbsolute()) {
            if (params.isParameterTrue(ClientPNames.REJECT_RELATIVE_REDIRECT)) {
                throw new ProtocolException("Relative redirect location '"
                        + uri + "' not allowed");
            }
            // Adjust location URI
            HttpHost target = (HttpHost) context.getAttribute(
                    ExecutionContext.HTTP_TARGET_HOST);
            if (target == null) {
                throw new IllegalStateException("Target host not available " +
                        "in the HTTP context");
            }

            HttpRequest request = (HttpRequest) context.getAttribute(
                    ExecutionContext.HTTP_REQUEST);

            try {
                URI requestURI = new URI(request.getRequestLine().getUri());
                URI absoluteRequestURI = URIUtils.rewriteURI(requestURI, target, true);
                uri = URIUtils.resolve(absoluteRequestURI, uri);
            } catch (URISyntaxException ex) {
                throw new ProtocolException(ex.getMessage(), ex);
            }
        }

        if (params.isParameterFalse(ClientPNames.ALLOW_CIRCULAR_REDIRECTS)) {

            RedirectLocations redirectLocations = (RedirectLocations) context.getAttribute(
                    REDIRECT_LOCATIONS);

            if (redirectLocations == null) {
                redirectLocations = new RedirectLocations();
                context.setAttribute(REDIRECT_LOCATIONS, redirectLocations);
            }

            URI redirectURI;
            if (uri.getFragment() != null) {
                try {
                    HttpHost target = new HttpHost(
                            uri.getHost(),
                            uri.getPort(),
                            uri.getScheme());
                    redirectURI = URIUtils.rewriteURI(uri, target, true);
                } catch (URISyntaxException ex) {
                    throw new ProtocolException(ex.getMessage(), ex);
                }
            } else {
                redirectURI = uri;
            }

            if (redirectLocations.contains(redirectURI)) {
                throw new CircularRedirectException("Circular redirect to '" +
                        redirectURI + "'");
            } else {
                redirectLocations.add(redirectURI);
            }
        }

        return uri;
    }
}