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[Sone.git] / src / main / java / net / pterodactylus / sone / fcp / FcpInterface.java
1 /*
2  * Sone - FcpInterface.java - Copyright © 2011 David Roden
3  *
4  * This program is free software: you can redistribute it and/or modify
5  * it under the terms of the GNU General Public License as published by
6  * the Free Software Foundation, either version 3 of the License, or
7  * (at your option) any later version.
8  *
9  * This program is distributed in the hope that it will be useful,
10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
12  * GNU General Public License for more details.
13  *
14  * You should have received a copy of the GNU General Public License
15  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
16  */
17
18 package net.pterodactylus.sone.fcp;
19
20 import java.util.Collections;
21 import java.util.HashMap;
22 import java.util.Map;
23 import java.util.logging.Level;
24 import java.util.logging.Logger;
25
26 import net.pterodactylus.sone.core.Core;
27 import net.pterodactylus.sone.freenet.fcp.Command.AccessType;
28 import net.pterodactylus.sone.freenet.fcp.Command.ErrorResponse;
29 import net.pterodactylus.sone.freenet.fcp.Command.Response;
30 import net.pterodactylus.sone.freenet.fcp.FcpException;
31 import net.pterodactylus.util.logging.Logging;
32 import net.pterodactylus.util.validation.Validation;
33 import freenet.pluginmanager.FredPluginFCP;
34 import freenet.pluginmanager.PluginNotFoundException;
35 import freenet.pluginmanager.PluginReplySender;
36 import freenet.support.SimpleFieldSet;
37 import freenet.support.api.Bucket;
38
39 /**
40  * Implementation of an FCP interface for other clients or plugins to
41  * communicate with Sone.
42  *
43  * @author <a href="mailto:bombe@pterodactylus.net">David ‘Bombe’ Roden</a>
44  */
45 public class FcpInterface {
46
47         /**
48          * The action level that full access for the FCP connection is required.
49          *
50          * @author <a href="mailto:bombe@pterodactylus.net">David ‘Bombe’ Roden</a>
51          */
52         public enum FullAccessRequired {
53
54                 /** No action requires full access. */
55                 NO,
56
57                 /** All writing actions require full access. */
58                 WRITING,
59
60                 /** All actions require full access. */
61                 ALWAYS,
62
63         }
64
65         /** The logger. */
66         private static final Logger logger = Logging.getLogger(FcpInterface.class);
67
68         /** Whether the FCP interface is currently active. */
69         private volatile boolean active;
70
71         /** What function full access is required for. */
72         private volatile FullAccessRequired fullAccessRequired = FullAccessRequired.ALWAYS;
73
74         /** All available FCP commands. */
75         private final Map<String, AbstractSoneCommand> commands = Collections.synchronizedMap(new HashMap<String, AbstractSoneCommand>());
76
77         /**
78          * Creates a new FCP interface.
79          *
80          * @param core
81          *            The core
82          */
83         public FcpInterface(Core core) {
84                 commands.put("Version", new VersionCommand(core));
85                 commands.put("GetLocalSones", new GetLocalSonesCommand(core));
86                 commands.put("GetSones", new GetSonesCommand(core));
87                 commands.put("GetSone", new GetSoneCommand(core));
88                 commands.put("GetPost", new GetPostCommand(core));
89                 commands.put("GetPosts", new GetPostsCommand(core));
90                 commands.put("GetPostFeed", new GetPostFeedCommand(core));
91                 commands.put("LikePost", new LikePostCommand(core));
92                 commands.put("LikeReply", new LikeReplyCommand(core));
93                 commands.put("CreatePost", new CreatePostCommand(core));
94                 commands.put("CreateReply", new CreateReplyCommand(core));
95                 commands.put("DeletePost", new DeletePostCommand(core));
96                 commands.put("DeleteReply", new DeleteReplyCommand(core));
97         }
98
99         //
100         // ACCESSORS
101         //
102
103         /**
104          * Sets whether the FCP interface should handle requests. If {@code active}
105          * is {@code false}, all requests are answered with an error.
106          *
107          * @param active
108          *            {@code true} to activate the FCP interface, {@code false} to
109          *            deactivate the FCP interface
110          */
111         public void setActive(boolean active) {
112                 this.active = active;
113         }
114
115         /**
116          * Sets the action level for which full FCP access is required.
117          *
118          * @param fullAccessRequired
119          *            The action level for which full FCP access is required
120          */
121         public void setFullAccessRequired(FullAccessRequired fullAccessRequired) {
122                 Validation.begin().isNotNull("FullAccessRequired", fullAccessRequired).check();
123                 this.fullAccessRequired = fullAccessRequired;
124         }
125
126         //
127         // ACTIONS
128         //
129
130         /**
131          * Handles a plugin FCP request.
132          *
133          * @param pluginReplySender
134          *            The reply sender
135          * @param parameters
136          *            The message parameters
137          * @param data
138          *            The message data (may be {@code null})
139          * @param accessType
140          *            One of {@link FredPluginFCP#ACCESS_DIRECT},
141          *            {@link FredPluginFCP#ACCESS_FCP_FULL},
142          *            {@link FredPluginFCP#ACCESS_FCP_RESTRICTED}
143          */
144         public void handle(PluginReplySender pluginReplySender, SimpleFieldSet parameters, Bucket data, int accessType) {
145                 if (!active) {
146                         try {
147                                 sendReply(pluginReplySender, null, new ErrorResponse(400, "FCP Interface deactivated"));
148                         } catch (PluginNotFoundException pnfe1) {
149                                 logger.log(Level.FINE, "Could not set error to plugin.", pnfe1);
150                         }
151                         return;
152                 }
153                 AbstractSoneCommand command = commands.get(parameters.get("Message"));
154                 if ((accessType == FredPluginFCP.ACCESS_FCP_RESTRICTED) && (((fullAccessRequired == FullAccessRequired.WRITING) && command.requiresWriteAccess()) || (fullAccessRequired == FullAccessRequired.ALWAYS))) {
155                         try {
156                                 sendReply(pluginReplySender, null, new ErrorResponse(401, "Not authorized"));
157                         } catch (PluginNotFoundException pnfe1) {
158                                 logger.log(Level.FINE, "Could not set error to plugin.", pnfe1);
159                         }
160                         return;
161                 }
162                 try {
163                         if (command == null) {
164                                 sendReply(pluginReplySender, null, new ErrorResponse("Unrecognized Message: " + parameters.get("Message")));
165                                 return;
166                         }
167                         String identifier = parameters.get("Identifier");
168                         if ((identifier == null) || (identifier.length() == 0)) {
169                                 sendReply(pluginReplySender, null, new ErrorResponse("Missing Identifier."));
170                                 return;
171                         }
172                         try {
173                                 Response response = command.execute(parameters, data, AccessType.values()[accessType]);
174                                 sendReply(pluginReplySender, identifier, response);
175                         } catch (FcpException fe1) {
176                                 logger.log(Level.WARNING, "Could not process FCP command “%s”.", command);
177                                 sendReply(pluginReplySender, identifier, new ErrorResponse("Error executing command: " + fe1.getMessage()));
178                         }
179                 } catch (PluginNotFoundException pnfe1) {
180                         logger.log(Level.WARNING, "Could not find destination plugin: " + pluginReplySender);
181                 }
182         }
183
184         //
185         // PRIVATE METHODS
186         //
187
188         /**
189          * Sends the given response to the given plugin.
190          *
191          * @param pluginReplySender
192          *            The reply sender
193          * @param identifier
194          *            The identifier (may be {@code null})
195          * @param response
196          *            The response to send
197          * @throws PluginNotFoundException
198          *             if the plugin can not be found
199          */
200         private void sendReply(PluginReplySender pluginReplySender, String identifier, Response response) throws PluginNotFoundException {
201                 SimpleFieldSet replyParameters = response.getReplyParameters();
202                 if (identifier != null) {
203                         replyParameters.putOverwrite("Identifier", identifier);
204                 }
205                 if (response.hasData()) {
206                         pluginReplySender.send(replyParameters, response.getData());
207                 } else if (response.hasBucket()) {
208                         pluginReplySender.send(replyParameters, response.getBucket());
209                 } else {
210                         pluginReplySender.send(replyParameters);
211                 }
212         }
213
214 }