org.eclipse.orion.server.servlets.JsonURIUnqualificationStrategy.java Source code

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Here is the source code for org.eclipse.orion.server.servlets.JsonURIUnqualificationStrategy.java

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/*******************************************************************************
 * Copyright (c) 2012 IBM Corporation and others.
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 * 
 * Contributors:
 *     IBM Corporation - initial API and implementation
 *******************************************************************************/
package org.eclipse.orion.server.servlets;

import java.net.URI;
import java.net.URISyntaxException;
import javax.servlet.http.HttpServletRequest;
import org.eclipse.orion.internal.server.servlets.ProtocolConstants;
import org.json.*;

/**
 * Controls which URLs found in JSON API response bodies will be "unqualified" (rewritten to remove the hostname 
 * and port of this server).
 */
public abstract class JsonURIUnqualificationStrategy {
    /**
     * A strategy that unqualifies all URLs in the JSON body.
     */
    public static final JsonURIUnqualificationStrategy ALL = new JsonURIUnqualificationStrategy() {
        @Override
        protected URI unqualifyObjectProperty(String key, URI uri, String scheme, String hostname, int port) {
            return unqualifyURI(uri, scheme, hostname, port);
        }

        @Override
        protected URI unqualifyArrayValue(int index, URI uri, String scheme, String hostname, int port) {
            return unqualifyURI(uri, scheme, hostname, port);
        }
    };
    /**
     * A strategy that unqualifies only the URLs that are values of a "Location" key in JSON objects.
     */
    public static final JsonURIUnqualificationStrategy LOCATION_ONLY = new JsonURIUnqualificationStrategy() {
        @Override
        protected URI unqualifyObjectProperty(String key, URI uri, String scheme, String hostname, int port) {
            if (!ProtocolConstants.KEY_LOCATION.equals(key))
                return uri;
            else
                return unqualifyURI(uri, scheme, hostname, port);
        }

        @Override
        protected URI unqualifyArrayValue(int index, URI uri, String scheme, String hostname, int port) {
            return uri;
        }
    };

    public void run(HttpServletRequest req, Object result) {
        rewrite(result, req.getScheme(), req.getServerName(), req.getServerPort(), req.getContextPath());
    }

    private void rewrite(JSONObject json, String scheme, String hostname, int port, String contextPath) {
        String[] names = JSONObject.getNames(json);
        if (names == null)
            return;
        for (String name : names) {
            Object o = json.opt(name);
            if (o instanceof URI) {
                try {
                    URI uri = (URI) o;
                    if ("orion".equals(uri.getScheme())) {
                        uri = new URI(null, null, contextPath + uri.getPath(), uri.getQuery(), uri.getFragment());
                    }
                    json.put(name, unqualifyObjectProperty(name, uri, scheme, hostname, port));
                } catch (JSONException e) {
                } catch (URISyntaxException e) {
                }
            } else if (o instanceof String) {
                String string = (String) o;
                if (string.startsWith(scheme) || string.startsWith("orion:/")) {
                    try {
                        URI uri = new URI(string);
                        if ("orion".equals(uri.getScheme())) {
                            uri = new URI(null, null, contextPath + uri.getPath(), uri.getQuery(),
                                    uri.getFragment());
                        }
                        json.put(name, unqualifyObjectProperty(name, uri, scheme, hostname, port));
                    } catch (JSONException e) {
                    } catch (URISyntaxException e) {
                    }
                }
            } else {
                rewrite(o, scheme, hostname, port, contextPath);
            }
        }
    }

    private void rewrite(Object o, String scheme, String hostname, int port, String contextPath) {
        if (o instanceof JSONObject) {
            rewrite((JSONObject) o, scheme, hostname, port, contextPath);
        } else if (o instanceof JSONArray) {
            JSONArray a = (JSONArray) o;
            for (int i = 0; i < a.length(); i++) {
                Object v = a.opt(i);
                if (v instanceof URI) {
                    try {
                        a.put(i, unqualifyArrayValue(i, (URI) v, scheme, hostname, port));
                    } catch (JSONException e) {
                    }
                } else if (v instanceof String) {
                    String string = (String) v;
                    if (string.startsWith(scheme)) {
                        try {
                            a.put(i, unqualifyArrayValue(i, new URI(string), scheme, hostname, port));
                        } catch (JSONException e) {
                        } catch (URISyntaxException e) {
                        }
                    }
                } else {
                    rewrite(v, scheme, hostname, port, contextPath);
                }
            }
        }
    }

    protected abstract URI unqualifyObjectProperty(String key, URI uri, String scheme, String hostname, int port);

    protected abstract URI unqualifyArrayValue(int index, URI uri, String scheme, String hostname, int port);

    protected static URI unqualifyURI(URI uri, String scheme, String hostname, int port) {
        URI simpleURI = uri;
        int uriPort = uri.getPort();
        if (uriPort == -1) {
            uriPort = getDefaultPort(uri.getScheme());
        }
        if (scheme.equals(uri.getScheme()) && hostname.equals(uri.getHost()) && port == uriPort) {
            try {
                simpleURI = new URI(null, null, null, -1, uri.getPath(), uri.getQuery(), uri.getFragment());
            } catch (URISyntaxException e) {
                simpleURI = uri;
            }
        }
        return simpleURI;
    }

    private static int getDefaultPort(String scheme) {
        if ("http".equalsIgnoreCase(scheme)) {
            return 80;
        }
        if ("https".equalsIgnoreCase(scheme)) {
            return 443;
        }
        return -1;
    }
}