jgit/org.eclipse.jgit.http.server/src/org/eclipse/jgit/http/server/InfoRefsServlet.java

/*
 * Copyright (C) 2009-2010, Google Inc.
 * and other copyright owners as documented in the project's IP log.
 *
 * This program and the accompanying materials are made available
 * under the terms of the Eclipse Distribution License v1.0 which
 * accompanies this distribution, is reproduced below, and is
 * available at http://www.eclipse.org/org/documents/edl-v10.php
 *
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or
 * without modification, are permitted provided that the following
 * conditions are met:
 *
 * - Redistributions of source code must retain the above copyright
 *   notice, this list of conditions and the following disclaimer.
 *
 * - 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.
 *
 * - Neither the name of the Eclipse Foundation, Inc. nor the
 *   names of its contributors may be used to endorse or promote
 *   products derived from this software without specific prior
 *   written permission.
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 * 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
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package org.eclipse.jgit.http.server;

import static org.eclipse.jgit.http.server.ServletUtils.getRepository;
import static org.eclipse.jgit.http.server.ServletUtils.send;

import java.io.IOException;
import java.util.HashMap;
import java.util.Map;

import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import org.eclipse.jgit.lib.Constants;
import org.eclipse.jgit.lib.Ref;
import org.eclipse.jgit.lib.Repository;
import org.eclipse.jgit.revwalk.RevFlag;
import org.eclipse.jgit.revwalk.RevWalk;
import org.eclipse.jgit.transport.RefAdvertiser;
import org.eclipse.jgit.util.HttpSupport;

/** Send a complete list of current refs, including peeled values for tags. */
class InfoRefsServlet extends HttpServlet {
	private static final long serialVersionUID = 1L;

	public void doGet(final HttpServletRequest req,
			final HttpServletResponse rsp) throws IOException {
		// Assume a dumb client and send back the dumb client
		// version of the info/refs file.
		final byte[] raw = dumbHttp(req);
		rsp.setContentType(HttpSupport.TEXT_PLAIN);
		rsp.setCharacterEncoding(Constants.CHARACTER_ENCODING);
		send(raw, req, rsp);
	}

	private byte[] dumbHttp(final HttpServletRequest req) throws IOException {
		final Repository db = getRepository(req);
		final RevWalk walk = new RevWalk(db);
		final RevFlag ADVERTISED = walk.newFlag("ADVERTISED");
		final StringBuilder out = new StringBuilder();
		final RefAdvertiser adv = new RefAdvertiser() {
			@Override
			protected void writeOne(final CharSequence line) {
				// Whoever decided that info/refs should use a different
				// delimiter than the native git:// protocol shouldn't
				// be allowed to design this sort of stuff. :-(
				out.append(line.toString().replace(' ', '\t'));
			}

			@Override
			protected void end() {
				// No end marker required for info/refs format.
			}
		};
		adv.init(walk, ADVERTISED);
		adv.setDerefTags(true);

		Map<String, Ref> refs = new HashMap<String, Ref>(db.getAllRefs());
		refs.remove(Constants.HEAD);
		adv.send(refs.values());
		return out.toString().getBytes(Constants.CHARACTER_ENCODING);
	}
}