core/src/main/java/org/nanohttpd/protocols/http/NanoHTTPD.java

package org.nanohttpd.protocols.http;

/*
 * #%L
 * NanoHttpd-Core
 * %%
 * Copyright (C) 2012 - 2016 nanohttpd
 * %%
 * Redistribution and use in source and binary forms, with or without modification,
 * are permitted provided that the following conditions are met:
 * 
 * 1. Redistributions of source code must retain the above copyright notice, this
 *    list of conditions and the following disclaimer.
 * 
 * 2. Redistributions in binary form must reproduce the above copyright notice,
 *    this list of conditions and the following disclaimer in the documentation
 *    and/or other materials provided with the distribution.
 * 
 * 3. Neither the name of the nanohttpd nor the names of its contributors
 *    may be used to endorse or promote products derived from this software without
 *    specific prior written permission.
 * 
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 * IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
 * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE
 * OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
 * OF THE POSSIBILITY OF SUCH DAMAGE.
 * #L%
 */

import java.io.Closeable;
import java.io.IOException;
import java.io.InputStream;
import java.io.UnsupportedEncodingException;
import java.net.ServerSocket;
import java.net.Socket;
import java.net.URL;
import java.net.URLDecoder;
import java.security.KeyStore;
import java.util.ArrayList;
import java.util.Enumeration;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.Properties;
import java.util.StringTokenizer;
import java.util.logging.Level;
import java.util.logging.Logger;
import java.util.regex.Pattern;

import javax.net.ssl.KeyManager;
import javax.net.ssl.KeyManagerFactory;
import javax.net.ssl.SSLContext;
import javax.net.ssl.SSLServerSocketFactory;
import javax.net.ssl.TrustManagerFactory;

import org.nanohttpd.protocols.http.response.Response;
import org.nanohttpd.protocols.http.response.Status;
import org.nanohttpd.protocols.http.sockets.DefaultServerSocketFactory;
import org.nanohttpd.protocols.http.sockets.SecureServerSocketFactory;
import org.nanohttpd.protocols.http.tempfiles.DefaultTempFileManagerFactory;
import org.nanohttpd.protocols.http.tempfiles.ITempFileManager;
import org.nanohttpd.protocols.http.threading.DefaultAsyncRunner;
import org.nanohttpd.protocols.http.threading.IAsyncRunner;
import org.nanohttpd.util.IFactory;
import org.nanohttpd.util.IFactoryThrowing;
import org.nanohttpd.util.IHandler;

/**
 * A simple, tiny, nicely embeddable HTTP server in Java
 * <p/>
 * <p/>
 * NanoHTTPD
 * <p>
 * Copyright (c) 2012-2013 by Paul S. Hawke, 2001,2005-2013 by Jarno Elonen,
 * 2010 by Konstantinos Togias
 * </p>
 * <p/>
 * <p/>
 * <b>Features + limitations: </b>
 * <ul>
 * <p/>
 * <li>Only one Java file</li>
 * <li>Java 5 compatible</li>
 * <li>Released as open source, Modified BSD licence</li>
 * <li>No fixed config files, logging, authorization etc. (Implement yourself if
 * you need them.)</li>
 * <li>Supports parameter parsing of GET and POST methods (+ rudimentary PUT
 * support in 1.25)</li>
 * <li>Supports both dynamic content and file serving</li>
 * <li>Supports file upload (since version 1.2, 2010)</li>
 * <li>Supports partial content (streaming)</li>
 * <li>Supports ETags</li>
 * <li>Never caches anything</li>
 * <li>Doesn't limit bandwidth, request time or simultaneous connections</li>
 * <li>Default code serves files and shows all HTTP parameters and headers</li>
 * <li>File server supports directory listing, index.html and index.htm</li>
 * <li>File server supports partial content (streaming)</li>
 * <li>File server supports ETags</li>
 * <li>File server does the 301 redirection trick for directories without '/'</li>
 * <li>File server supports simple skipping for files (continue download)</li>
 * <li>File server serves also very long files without memory overhead</li>
 * <li>Contains a built-in list of most common MIME types</li>
 * <li>All header names are converted to lower case so they don't vary between
 * browsers/clients</li>
 * <p/>
 * </ul>
 * <p/>
 * <p/>
 * <b>How to use: </b>
 * <ul>
 * <p/>
 * <li>Subclass and implement serve() and embed to your own program</li>
 * <p/>
 * </ul>
 * <p/>
 * See the separate "LICENSE.md" file for the distribution license (Modified BSD
 * licence)
 */
public abstract class NanoHTTPD {

    public static final String CONTENT_DISPOSITION_REGEX = "([ |\t]*Content-Disposition[ |\t]*:)(.*)";

    public static final Pattern CONTENT_DISPOSITION_PATTERN = Pattern.compile(CONTENT_DISPOSITION_REGEX, Pattern.CASE_INSENSITIVE);

    public static final String CONTENT_TYPE_REGEX = "([ |\t]*content-type[ |\t]*:)(.*)";

    public static final Pattern CONTENT_TYPE_PATTERN = Pattern.compile(CONTENT_TYPE_REGEX, Pattern.CASE_INSENSITIVE);

    public static final String CONTENT_DISPOSITION_ATTRIBUTE_REGEX = "[ |\t]*([a-zA-Z]*)[ |\t]*=[ |\t]*['|\"]([^\"^']*)['|\"]";

    public static final Pattern CONTENT_DISPOSITION_ATTRIBUTE_PATTERN = Pattern.compile(CONTENT_DISPOSITION_ATTRIBUTE_REGEX);

    public static final class ResponseException extends Exception {

        private static final long serialVersionUID = 6569838532917408380L;

        private final Status status;

        public ResponseException(Status status, String message) {
            super(message);
            this.status = status;
        }

        public ResponseException(Status status, String message, Exception e) {
            super(message, e);
            this.status = status;
        }

        public Status getStatus() {
            return this.status;
        }
    }

    /**
     * Maximum time to wait on Socket.getInputStream().read() (in milliseconds)
     * This is required as the Keep-Alive HTTP connections would otherwise block
     * the socket reading thread forever (or as long the browser is open).
     */
    public static final int SOCKET_READ_TIMEOUT = 5000;

    /**
     * Common MIME type for dynamic content: plain text
     */
    public static final String MIME_PLAINTEXT = "text/plain";

    /**
     * Common MIME type for dynamic content: html
     */
    public static final String MIME_HTML = "text/html";

    /**
     * Pseudo-Parameter to use to store the actual query string in the
     * parameters map for later re-processing.
     */
    private static final String QUERY_STRING_PARAMETER = "NanoHttpd.QUERY_STRING";

    /**
     * logger to log to.
     */
    public static final Logger LOG = Logger.getLogger(NanoHTTPD.class.getName());

    /**
     * Hashtable mapping (String)FILENAME_EXTENSION -> (String)MIME_TYPE
     */
    protected static Map<String, String> MIME_TYPES;

    public static Map<String, String> mimeTypes() {
        if (MIME_TYPES == null) {
            MIME_TYPES = new HashMap<String, String>();
            loadMimeTypes(MIME_TYPES, "META-INF/nanohttpd/default-mimetypes.properties");
            loadMimeTypes(MIME_TYPES, "META-INF/nanohttpd/mimetypes.properties");
            if (MIME_TYPES.isEmpty()) {
                LOG.log(Level.WARNING, "no mime types found in the classpath! please provide mimetypes.properties");
            }
        }
        return MIME_TYPES;
    }

    @SuppressWarnings({
        "unchecked",
        "rawtypes"
    })
    private static void loadMimeTypes(Map<String, String> result, String resourceName) {
        try {
            Enumeration<URL> resources = NanoHTTPD.class.getClassLoader().getResources(resourceName);
            while (resources.hasMoreElements()) {
                URL url = (URL) resources.nextElement();
                Properties properties = new Properties();
                InputStream stream = null;
                try {
                    stream = url.openStream();
                    properties.load(stream);
                } catch (IOException e) {
                    LOG.log(Level.SEVERE, "could not load mimetypes from " + url, e);
                } finally {
                    safeClose(stream);
                }
                result.putAll((Map) properties);
            }
        } catch (IOException e) {
            LOG.log(Level.INFO, "no mime types available at " + resourceName);
        }
    };

    /**
     * Creates an SSLSocketFactory for HTTPS. Pass a loaded KeyStore and an
     * array of loaded KeyManagers. These objects must properly
     * loaded/initialized by the caller.
     */
    public static SSLServerSocketFactory makeSSLSocketFactory(KeyStore loadedKeyStore, KeyManager[] keyManagers) throws IOException {
        SSLServerSocketFactory res = null;
        try {
            TrustManagerFactory trustManagerFactory = TrustManagerFactory.getInstance(TrustManagerFactory.getDefaultAlgorithm());
            trustManagerFactory.init(loadedKeyStore);
            SSLContext ctx = SSLContext.getInstance("TLS");
            ctx.init(keyManagers, trustManagerFactory.getTrustManagers(), null);
            res = ctx.getServerSocketFactory();
        } catch (Exception e) {
            throw new IOException(e.getMessage());
        }
        return res;
    }

    /**
     * Creates an SSLSocketFactory for HTTPS. Pass a loaded KeyStore and a
     * loaded KeyManagerFactory. These objects must properly loaded/initialized
     * by the caller.
     */
    public static SSLServerSocketFactory makeSSLSocketFactory(KeyStore loadedKeyStore, KeyManagerFactory loadedKeyFactory) throws IOException {
        try {
            return makeSSLSocketFactory(loadedKeyStore, loadedKeyFactory.getKeyManagers());
        } catch (Exception e) {
            throw new IOException(e.getMessage());
        }
    }

    /**
     * Creates an SSLSocketFactory for HTTPS. Pass a KeyStore resource with your
     * certificate and passphrase
     */
    public static SSLServerSocketFactory makeSSLSocketFactory(String keyAndTrustStoreClasspathPath, char[] passphrase) throws IOException {
        try {
            KeyStore keystore = KeyStore.getInstance(KeyStore.getDefaultType());
            InputStream keystoreStream = NanoHTTPD.class.getResourceAsStream(keyAndTrustStoreClasspathPath);

            if (keystoreStream == null) {
                throw new IOException("Unable to load keystore from classpath: " + keyAndTrustStoreClasspathPath);
            }

            keystore.load(keystoreStream, passphrase);
            KeyManagerFactory keyManagerFactory = KeyManagerFactory.getInstance(KeyManagerFactory.getDefaultAlgorithm());
            keyManagerFactory.init(keystore, passphrase);
            return makeSSLSocketFactory(keystore, keyManagerFactory);
        } catch (Exception e) {
            throw new IOException(e.getMessage());
        }
    }

    /**
     * Get MIME type from file name extension, if possible
     * 
     * @param uri
     *            the string representing a file
     * @return the connected mime/type
     */
    public static String getMimeTypeForFile(String uri) {
        int dot = uri.lastIndexOf('.');
        String mime = null;
        if (dot >= 0) {
            mime = mimeTypes().get(uri.substring(dot + 1).toLowerCase());
        }
        return mime == null ? "application/octet-stream" : mime;
    }

    public static final void safeClose(Object closeable) {
        try {
            if (closeable != null) {
                if (closeable instanceof Closeable) {
                    ((Closeable) closeable).close();
                } else if (closeable instanceof Socket) {
                    ((Socket) closeable).close();
                } else if (closeable instanceof ServerSocket) {
                    ((ServerSocket) closeable).close();
                } else {
                    throw new IllegalArgumentException("Unknown object to close");
                }
            }
        } catch (IOException e) {
            NanoHTTPD.LOG.log(Level.SEVERE, "Could not close", e);
        }
    }

    public final String hostname;

    public final int myPort;

    private volatile ServerSocket myServerSocket;

    public ServerSocket getMyServerSocket() {
        return myServerSocket;
    }

    private IFactoryThrowing<ServerSocket, IOException> serverSocketFactory = new DefaultServerSocketFactory();

    private Thread myThread;

    private IHandler<IHTTPSession, Response> httpHandler;

    protected List<IHandler<IHTTPSession, Response>> interceptors = new ArrayList<IHandler<IHTTPSession, Response>>(4);

    /**
     * Pluggable strategy for asynchronously executing requests.
     */
    protected IAsyncRunner asyncRunner;

    /**
     * Pluggable strategy for creating and cleaning up temporary files.
     */
    private IFactory<ITempFileManager> tempFileManagerFactory;

    /**
     * Constructs an HTTP server on given port.
     */
    public NanoHTTPD(int port) {
        this(null, port);
    }

    // -------------------------------------------------------------------------------
    // //
    //
    // Threading Strategy.
    //
    // -------------------------------------------------------------------------------
    // //

    /**
     * Constructs an HTTP server on given hostname and port.
     */
    public NanoHTTPD(String hostname, int port) {
        this.hostname = hostname;
        this.myPort = port;
        setTempFileManagerFactory(new DefaultTempFileManagerFactory());
        setAsyncRunner(new DefaultAsyncRunner());

        // creates a default handler that redirects to deprecated serve();
        this.httpHandler = new IHandler<IHTTPSession, Response>() {

            @Override
            public Response handle(IHTTPSession input) {
                return NanoHTTPD.this.serve(input);
            }
        };
    }

    public void setHTTPHandler(IHandler<IHTTPSession, Response> handler) {
        this.httpHandler = handler;
    }

    public void addHTTPInterceptor(IHandler<IHTTPSession, Response> interceptor) {
        interceptors.add(interceptor);
    }

    /**
     * Forcibly closes all connections that are open.
     */
    public synchronized void closeAllConnections() {
        stop();
    }

    /**
     * create a instance of the client handler, subclasses can return a subclass
     * of the ClientHandler.
     * 
     * @param finalAccept
     *            the socket the cleint is connected to
     * @param inputStream
     *            the input stream
     * @return the client handler
     */
    protected ClientHandler createClientHandler(final Socket finalAccept, final InputStream inputStream) {
        return new ClientHandler(this, inputStream, finalAccept);
    }

    /**
     * Instantiate the server runnable, can be overwritten by subclasses to
     * provide a subclass of the ServerRunnable.
     * 
     * @param timeout
     *            the socet timeout to use.
     * @return the server runnable.
     */
    protected ServerRunnable createServerRunnable(final int timeout) {
        return new ServerRunnable(this, timeout);
    }

    /**
     * Decode parameters from a URL, handing the case where a single parameter
     * name might have been supplied several times, by return lists of values.
     * In general these lists will contain a single element.
     * 
     * @param parms
     *            original <b>NanoHTTPD</b> parameters values, as passed to the
     *            <code>serve()</code> method.
     * @return a map of <code>String</code> (parameter name) to
     *         <code>List&lt;String&gt;</code> (a list of the values supplied).
     */
    protected static Map<String, List<String>> decodeParameters(Map<String, String> parms) {
        return decodeParameters(parms.get(NanoHTTPD.QUERY_STRING_PARAMETER));
    }

    // -------------------------------------------------------------------------------
    // //

    /**
     * Decode parameters from a URL, handing the case where a single parameter
     * name might have been supplied several times, by return lists of values.
     * In general these lists will contain a single element.
     * 
     * @param queryString
     *            a query string pulled from the URL.
     * @return a map of <code>String</code> (parameter name) to
     *         <code>List&lt;String&gt;</code> (a list of the values supplied).
     */
    protected static Map<String, List<String>> decodeParameters(String queryString) {
        Map<String, List<String>> parms = new HashMap<String, List<String>>();
        if (queryString != null) {
            StringTokenizer st = new StringTokenizer(queryString, "&");
            while (st.hasMoreTokens()) {
                String e = st.nextToken();
                int sep = e.indexOf('=');
                String propertyName = sep >= 0 ? decodePercent(e.substring(0, sep)).trim() : decodePercent(e).trim();
                if (!parms.containsKey(propertyName)) {
                    parms.put(propertyName, new ArrayList<String>());
                }
                String propertyValue = sep >= 0 ? decodePercent(e.substring(sep + 1)) : null;
                if (propertyValue != null) {
                    parms.get(propertyName).add(propertyValue);
                }
            }
        }
        return parms;
    }

    /**
     * Decode percent encoded <code>String</code> values.
     * 
     * @param str
     *            the percent encoded <code>String</code>
     * @return expanded form of the input, for example "foo%20bar" becomes
     *         "foo bar"
     */
    public static String decodePercent(String str) {
        String decoded = null;
        try {
            decoded = URLDecoder.decode(str, "UTF8");
        } catch (UnsupportedEncodingException ignored) {
            NanoHTTPD.LOG.log(Level.WARNING, "Encoding not supported, ignored", ignored);
        }
        return decoded;
    }

    public final int getListeningPort() {
        return this.myServerSocket == null ? -1 : this.myServerSocket.getLocalPort();
    }

    public final boolean isAlive() {
        return wasStarted() && !this.myServerSocket.isClosed() && this.myThread.isAlive();
    }

    public IFactoryThrowing<ServerSocket, IOException> getServerSocketFactory() {
        return serverSocketFactory;
    }

    public void setServerSocketFactory(IFactoryThrowing<ServerSocket, IOException> serverSocketFactory) {
        this.serverSocketFactory = serverSocketFactory;
    }

    public String getHostname() {
        return hostname;
    }

    public IFactory<ITempFileManager> getTempFileManagerFactory() {
        return tempFileManagerFactory;
    }

    /**
     * Call before start() to serve over HTTPS instead of HTTP
     */
    public void makeSecure(SSLServerSocketFactory sslServerSocketFactory, String[] sslProtocols) {
        this.serverSocketFactory = new SecureServerSocketFactory(sslServerSocketFactory, sslProtocols);
    }

    /**
     * This is the "master" method that delegates requests to handlers and makes
     * sure there is a response to every request. You are not supposed to call
     * or override this method in any circumstances. But no one will stop you if
     * you do. I'm a Javadoc, not Code Police.
     * 
     * @param session
     *            the incoming session
     * @return a response to the incoming session
     */
    public Response handle(IHTTPSession session) {
        for (IHandler<IHTTPSession, Response> interceptor : interceptors) {
            Response response = interceptor.handle(session);
            if (response != null)
                return response;
        }
        return httpHandler.handle(session);
    }

    /**
     * Override this to customize the server.
     * <p/>
     * <p/>
     * (By default, this returns a 404 "Not Found" plain text error response.)
     * 
     * @param session
     *            The HTTP session
     * @return HTTP response, see class Response for details
     */
    @Deprecated
    protected Response serve(IHTTPSession session) {
        return Response.newFixedLengthResponse(Status.NOT_FOUND, NanoHTTPD.MIME_PLAINTEXT, "Not Found");
    }

    /**
     * Pluggable strategy for asynchronously executing requests.
     * 
     * @param asyncRunner
     *            new strategy for handling threads.
     */
    public void setAsyncRunner(IAsyncRunner asyncRunner) {
        this.asyncRunner = asyncRunner;
    }

    /**
     * Pluggable strategy for creating and cleaning up temporary files.
     * 
     * @param tempFileManagerFactory
     *            new strategy for handling temp files.
     */
    public void setTempFileManagerFactory(IFactory<ITempFileManager> tempFileManagerFactory) {
        this.tempFileManagerFactory = tempFileManagerFactory;
    }

    /**
     * Start the server.
     * 
     * @throws IOException
     *             if the socket is in use.
     */
    public void start() throws IOException {
        start(NanoHTTPD.SOCKET_READ_TIMEOUT);
    }

    /**
     * Starts the server (in setDaemon(true) mode).
     */
    public void start(final int timeout) throws IOException {
        start(timeout, true);
    }

    /**
     * Start the server.
     * 
     * @param timeout
     *            timeout to use for socket connections.
     * @param daemon
     *            start the thread daemon or not.
     * @throws IOException
     *             if the socket is in use.
     */
    public void start(final int timeout, boolean daemon) throws IOException {
        this.myServerSocket = this.getServerSocketFactory().create();
        this.myServerSocket.setReuseAddress(true);

        ServerRunnable serverRunnable = createServerRunnable(timeout);
        this.myThread = new Thread(serverRunnable);
        this.myThread.setDaemon(daemon);
        this.myThread.setName("NanoHttpd Main Listener");
        this.myThread.start();
        while (!serverRunnable.hasBinded() && serverRunnable.getBindException() == null) {
            try {
                Thread.sleep(10L);
            } catch (Throwable e) {
                // on android this may not be allowed, that's why we
                // catch throwable the wait should be very short because we are
                // just waiting for the bind of the socket
            }
        }
        if (serverRunnable.getBindException() != null) {
            throw serverRunnable.getBindException();
        }
    }

    /**
     * Stop the server.
     */
    public void stop() {
        try {
            safeClose(this.myServerSocket);
            this.asyncRunner.closeAll();
            if (this.myThread != null) {
                this.myThread.join();
            }
        } catch (Exception e) {
            NanoHTTPD.LOG.log(Level.SEVERE, "Could not stop all connections", e);
        }
    }

    public final boolean wasStarted() {
        return this.myServerSocket != null && this.myThread != null;
    }
}