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1   /*
2    * Copyright (C) 2016, 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.internal.ketch;
45  
46  import java.util.Collection;
47  import java.util.Map;
48  
49  import org.eclipse.jgit.annotations.Nullable;
50  import org.eclipse.jgit.lib.Ref;
51  import org.eclipse.jgit.lib.Repository;
52  import org.eclipse.jgit.transport.ReceiveCommand;
53  
54  /**
55   * A push request sending objects to a replica, and its result.
56   * <p>
57   * Implementors of {@link KetchReplica} must populate the command result fields,
58   * {@link #setRefs(Map)}, and call one of
59   * {@link #setException(Repository, Throwable)} or {@link #done(Repository)} to
60   * finish processing.
61   */
62  public class ReplicaPushRequest {
63  	private final KetchReplica replica;
64  	private final Collection<ReceiveCommand> commands;
65  	private Map<String, Ref> refs;
66  	private Throwable exception;
67  	private boolean notified;
68  
69  	/**
70  	 * Construct a new push request for a replica.
71  	 *
72  	 * @param replica
73  	 *            the replica being pushed to.
74  	 * @param commands
75  	 *            commands to be executed.
76  	 */
77  	public ReplicaPushRequest(KetchReplica replica,
78  			Collection<ReceiveCommand> commands) {
79  		this.replica = replica;
80  		this.commands = commands;
81  	}
82  
83  	/** @return commands to be executed, and their results. */
84  	public Collection<ReceiveCommand> getCommands() {
85  		return commands;
86  	}
87  
88  	/** @return remote references, usually from the advertisement. */
89  	@Nullable
90  	public Map<String, Ref> getRefs() {
91  		return refs;
92  	}
93  
94  	/**
95  	 * @param refs
96  	 *            references observed from the replica.
97  	 */
98  	public void setRefs(Map<String, Ref> refs) {
99  		this.refs = refs;
100 	}
101 
102 	/** @return exception thrown, if any. */
103 	@Nullable
104 	public Throwable getException() {
105 		return exception;
106 	}
107 
108 	/**
109 	 * Mark the request as crashing with a communication error.
110 	 * <p>
111 	 * This method may take significant time acquiring the leader lock and
112 	 * updating the Ketch state machine with the failure.
113 	 *
114 	 * @param repo
115 	 *            local repository reference used by the push attempt.
116 	 * @param err
117 	 *            exception thrown during communication.
118 	 */
119 	public void setException(@Nullable Repository repo, Throwable err) {
120 		if (KetchReplica.log.isErrorEnabled()) {
121 			KetchReplica.log.error(describe("failed"), err); //$NON-NLS-1$
122 		}
123 		if (!notified) {
124 			notified = true;
125 			exception = err;
126 			replica.afterPush(repo, this);
127 		}
128 	}
129 
130 	/**
131 	 * Mark the request as completed without exception.
132 	 * <p>
133 	 * This method may take significant time acquiring the leader lock and
134 	 * updating the Ketch state machine with results from this replica.
135 	 *
136 	 * @param repo
137 	 *            local repository reference used by the push attempt.
138 	 */
139 	public void done(Repository repo) {
140 		if (KetchReplica.log.isDebugEnabled()) {
141 			KetchReplica.log.debug(describe("completed")); //$NON-NLS-1$
142 		}
143 		if (!notified) {
144 			notified = true;
145 			replica.afterPush(repo, this);
146 		}
147 	}
148 
149 	private String describe(String heading) {
150 		StringBuilder b = new StringBuilder();
151 		b.append("push to "); //$NON-NLS-1$
152 		b.append(replica.describeForLog());
153 		b.append(' ').append(heading).append(":\n"); //$NON-NLS-1$
154 		for (ReceiveCommand cmd : commands) {
155 			b.append(String.format(
156 					"  %-12s %-12s %s %s", //$NON-NLS-1$
157 					LeaderSnapshot.str(cmd.getOldId()),
158 					LeaderSnapshot.str(cmd.getNewId()),
159 					cmd.getRefName(),
160 					cmd.getResult()));
161 			if (cmd.getMessage() != null) {
162 				b.append(' ').append(cmd.getMessage());
163 			}
164 			b.append('\n');
165 		}
166 		return b.toString();
167 	}
168 }