1 /*
2 * Copyright (C) 2008-2010, Google Inc.
3 * and other copyright owners as documented in the project's IP log.
4 *
5 * This program and the accompanying materials are made available
6 * under the terms of the Eclipse Distribution License v1.0 which
7 * accompanies this distribution, is reproduced below, and is
8 * available at http://www.eclipse.org/org/documents/edl-v10.php
9 *
10 * All rights reserved.
11 *
12 * Redistribution and use in source and binary forms, with or
13 * without modification, are permitted provided that the following
14 * conditions are met:
15 *
16 * - Redistributions of source code must retain the above copyright
17 * notice, this list of conditions and the following disclaimer.
18 *
19 * - Redistributions in binary form must reproduce the above
20 * copyright notice, this list of conditions and the following
21 * disclaimer in the documentation and/or other materials provided
22 * with the distribution.
23 *
24 * - Neither the name of the Eclipse Foundation, Inc. nor the
25 * names of its contributors may be used to endorse or promote
26 * products derived from this software without specific prior
27 * written permission.
28 *
29 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
30 * CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
31 * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
32 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
33 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
34 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
35 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
36 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
37 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
38 * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
39 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
40 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
41 * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
42 */
43
44 package org.eclipse.jgit.transport;
45
46 import static java.nio.charset.StandardCharsets.UTF_8;
47
48 import java.io.IOException;
49 import java.io.OutputStream;
50 import java.io.OutputStreamWriter;
51 import java.io.Writer;
52 import java.text.MessageFormat;
53 import java.util.HashSet;
54 import java.util.Map;
55 import java.util.Set;
56 import java.util.TreeMap;
57
58 import org.eclipse.jgit.internal.JGitText;
59 import org.eclipse.jgit.internal.storage.pack.PackWriter;
60 import org.eclipse.jgit.lib.AnyObjectId;
61 import org.eclipse.jgit.lib.Constants;
62 import org.eclipse.jgit.lib.ObjectId;
63 import org.eclipse.jgit.lib.ObjectReader;
64 import org.eclipse.jgit.lib.ProgressMonitor;
65 import org.eclipse.jgit.lib.Ref;
66 import org.eclipse.jgit.lib.Repository;
67 import org.eclipse.jgit.revwalk.RevCommit;
68 import org.eclipse.jgit.storage.pack.PackConfig;
69
70 /**
71 * Creates a Git bundle file, for sneaker-net transport to another system.
72 * <p>
73 * Bundles generated by this class can be later read in from a file URI using
74 * the bundle transport, or from an application controlled buffer by the more
75 * generic {@link org.eclipse.jgit.transport.TransportBundleStream}.
76 * <p>
77 * Applications creating bundles need to call one or more <code>include</code>
78 * calls to reflect which objects should be available as refs in the bundle for
79 * the other side to fetch. At least one include is required to create a valid
80 * bundle file, and duplicate names are not permitted.
81 * <p>
82 * Optional <code>assume</code> calls can be made to declare commits which the
83 * recipient must have in order to fetch from the bundle file. Objects reachable
84 * from these assumed commits can be used as delta bases in order to reduce the
85 * overall bundle size.
86 */
87 public class BundleWriter {
88 private final Repository db;
89
90 private final ObjectReader reader;
91
92 private final Map<String, ObjectId> include;
93
94 private final Set<RevCommit> assume;
95
96 private final Set<ObjectId> tagTargets;
97
98 private PackConfig packConfig;
99
100 private ObjectCountCallback callback;
101
102 /**
103 * Create a writer for a bundle.
104 *
105 * @param repo
106 * repository where objects are stored.
107 */
108 public BundleWriter(Repository repo) {
109 db = repo;
110 reader = null;
111 include = new TreeMap<>();
112 assume = new HashSet<>();
113 tagTargets = new HashSet<>();
114 }
115
116 /**
117 * Create a writer for a bundle.
118 *
119 * @param or
120 * reader for reading objects. Will be closed at the end of {@link
121 * #writeBundle(ProgressMonitor, OutputStream)}, but readers may be
122 * reused after closing.
123 * @since 4.8
124 */
125 public BundleWriter(ObjectReader or) {
126 db = null;
127 reader = or;
128 include = new TreeMap<>();
129 assume = new HashSet<>();
130 tagTargets = new HashSet<>();
131 }
132
133 /**
134 * Set the configuration used by the pack generator.
135 *
136 * @param pc
137 * configuration controlling packing parameters. If null the
138 * source repository's settings will be used, or the default
139 * settings if constructed without a repo.
140 */
141 public void setPackConfig(PackConfig pc) {
142 this.packConfig = pc;
143 }
144
145 /**
146 * Include an object (and everything reachable from it) in the bundle.
147 *
148 * @param name
149 * name the recipient can discover this object as from the
150 * bundle's list of advertised refs . The name must be a valid
151 * ref format and must not have already been included in this
152 * bundle writer.
153 * @param id
154 * object to pack. Multiple refs may point to the same object.
155 */
156 public void include(String name, AnyObjectId id) {
157 boolean validRefName = Repository.isValidRefName(name) || Constants.HEAD.equals(name);
158 if (!validRefName)
159 throw new IllegalArgumentException(MessageFormat.format(JGitText.get().invalidRefName, name));
160 if (include.containsKey(name))
161 throw new IllegalStateException(JGitText.get().duplicateRef + name);
162 include.put(name, id.toObjectId());
163 }
164
165 /**
166 * Include a single ref (a name/object pair) in the bundle.
167 * <p>
168 * This is a utility function for:
169 * <code>include(r.getName(), r.getObjectId())</code>.
170 *
171 * @param r
172 * the ref to include.
173 */
174 public void include(Ref r) {
175 include(r.getName(), r.getObjectId());
176
177 if (r.getPeeledObjectId() != null)
178 tagTargets.add(r.getPeeledObjectId());
179
180 else if (r.getObjectId() != null
181 && r.getName().startsWith(Constants.R_HEADS))
182 tagTargets.add(r.getObjectId());
183 }
184
185 /**
186 * Assume a commit is available on the recipient's side.
187 * <p>
188 * In order to fetch from a bundle the recipient must have any assumed
189 * commit. Each assumed commit is explicitly recorded in the bundle header
190 * to permit the recipient to validate it has these objects.
191 *
192 * @param c
193 * the commit to assume being available. This commit should be
194 * parsed and not disposed in order to maximize the amount of
195 * debugging information available in the bundle stream.
196 */
197 public void assume(RevCommit c) {
198 if (c != null)
199 assume.add(c);
200 }
201
202 /**
203 * Generate and write the bundle to the output stream.
204 * <p>
205 * This method can only be called once per BundleWriter instance.
206 *
207 * @param monitor
208 * progress monitor to report bundle writing status to.
209 * @param os
210 * the stream the bundle is written to. The stream should be
211 * buffered by the caller. The caller is responsible for closing
212 * the stream.
213 * @throws java.io.IOException
214 * an error occurred reading a local object's data to include in
215 * the bundle, or writing compressed object data to the output
216 * stream.
217 */
218 public void writeBundle(ProgressMonitor monitor, OutputStream os)
219 throws IOException {
220 try (PackWriter packWriter = newPackWriter()) {
221 packWriter.setObjectCountCallback(callback);
222
223 final HashSet<ObjectId> inc = new HashSet<>();
224 final HashSet<ObjectId> exc = new HashSet<>();
225 inc.addAll(include.values());
226 for (RevCommit r : assume)
227 exc.add(r.getId());
228 packWriter.setIndexDisabled(true);
229 packWriter.setDeltaBaseAsOffset(true);
230 packWriter.setThin(!exc.isEmpty());
231 packWriter.setReuseValidatingObjects(false);
232 if (exc.isEmpty()) {
233 packWriter.setTagTargets(tagTargets);
234 }
235 packWriter.preparePack(monitor, inc, exc);
236
237 final Writer w = new OutputStreamWriter(os, UTF_8);
238 w.write(TransportBundle.V2_BUNDLE_SIGNATURE);
239 w.write('\n');
240
241 final char[] tmp = new char[Constants.OBJECT_ID_STRING_LENGTH];
242 for (RevCommit a : assume) {
243 w.write('-');
244 a.copyTo(tmp, w);
245 if (a.getRawBuffer() != null) {
246 w.write(' ');
247 w.write(a.getShortMessage());
248 }
249 w.write('\n');
250 }
251 for (Map.Entry<String, ObjectId> e : include.entrySet()) {
252 e.getValue().copyTo(tmp, w);
253 w.write(' ');
254 w.write(e.getKey());
255 w.write('\n');
256 }
257
258 w.write('\n');
259 w.flush();
260 packWriter.writePack(monitor, monitor, os);
261 }
262 }
263
264 private PackWriter newPackWriter() {
265 PackConfig pc = packConfig;
266 if (pc == null) {
267 pc = db != null ? new PackConfig/PackConfig.html#PackConfig">PackConfig(db) : new PackConfig();
268 }
269 return new PackWriter(pc, reader != null ? reader : db.newObjectReader());
270 }
271
272 /**
273 * Set the {@link org.eclipse.jgit.transport.ObjectCountCallback}.
274 * <p>
275 * It should be set before calling
276 * {@link #writeBundle(ProgressMonitor, OutputStream)}.
277 * <p>
278 * This callback will be passed on to
279 * {@link org.eclipse.jgit.internal.storage.pack.PackWriter#setObjectCountCallback}.
280 *
281 * @param callback
282 * the callback to set
283 * @return this object for chaining.
284 * @since 4.1
285 */
286 public BundleWriter setObjectCountCallback(ObjectCountCallback callback) {
287 this.callback = callback;
288 return this;
289 }
290 }