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1   /*
2    * Licensed to the Apache Software Foundation (ASF) under one or more
3    * contributor license agreements. See the NOTICE file distributed with
4    * this work for additional information regarding copyright ownership.
5    * The ASF licenses this file to You under the Apache license, Version 2.0
6    * (the "License"); you may not use this file except in compliance with
7    * the License. You may obtain a copy of the License at
8    *
9    *      http://www.apache.org/licenses/LICENSE-2.0
10   *
11   * Unless required by applicable law or agreed to in writing, software
12   * distributed under the License is distributed on an "AS IS" BASIS,
13   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14   * See the license for the specific language governing permissions and
15   * limitations under the license.
16   */
17  
18  package org.apache.logging.log4j.core.appender.rolling.action;
19  
20  import java.nio.file.Path;
21  import java.util.List;
22  import java.util.Objects;
23  
24  import javax.script.SimpleBindings;
25  
26  import org.apache.logging.log4j.Logger;
27  import org.apache.logging.log4j.core.Core;
28  import org.apache.logging.log4j.core.config.Configuration;
29  import org.apache.logging.log4j.core.config.plugins.Plugin;
30  import org.apache.logging.log4j.core.config.plugins.PluginConfiguration;
31  import org.apache.logging.log4j.core.config.plugins.PluginElement;
32  import org.apache.logging.log4j.core.config.plugins.PluginFactory;
33  import org.apache.logging.log4j.core.script.AbstractScript;
34  import org.apache.logging.log4j.core.script.ScriptFile;
35  import org.apache.logging.log4j.core.script.ScriptRef;
36  import org.apache.logging.log4j.status.StatusLogger;
37  
38  /**
39   * A condition of the {@link DeleteAction} where a user-provided script selects the files to delete from a provided
40   * list. The specified script may be a {@link Script}, a {@link ScriptFile} or a {@link ScriptRef}.
41   *
42   * @see #createCondition(AbstractScript, Configuration)
43   */
44  @Plugin(name = "ScriptCondition", category = Core.CATEGORY_NAME, printObject = true)
45  public class ScriptCondition {
46      private static Logger LOGGER = StatusLogger.getLogger();
47  
48      private final AbstractScript script;
49      private final Configuration configuration;
50  
51      /**
52       * Constructs a new ScriptCondition.
53       *
54       * @param script the script that can select files to delete
55       * @param configuration configuration containing the StrSubstitutor passed to the script
56       */
57      public ScriptCondition(final AbstractScript script, final Configuration configuration) {
58          this.script = Objects.requireNonNull(script, "script");
59          this.configuration = Objects.requireNonNull(configuration, "configuration");
60          if (!(script instanceof ScriptRef)) {
61              configuration.getScriptManager().addScript(script);
62          }
63      }
64  
65      /**
66       * Executes the script
67       *
68       * @param baseDir
69       * @param candidates
70       * @return
71       */
72      @SuppressWarnings("unchecked")
73      public List<PathWithAttributes> selectFilesToDelete(final Path basePath, final List<PathWithAttributes> candidates) {
74          final SimpleBindings bindings = new SimpleBindings();
75          bindings.put("basePath", basePath);
76          bindings.put("pathList", candidates);
77          bindings.putAll(configuration.getProperties());
78          bindings.put("configuration", configuration);
79          bindings.put("substitutor", configuration.getStrSubstitutor());
80          bindings.put("statusLogger", LOGGER);
81          final Object object = configuration.getScriptManager().execute(script.getName(), bindings);
82          return (List<PathWithAttributes>) object;
83      }
84  
85      /**
86       * Creates the ScriptCondition.
87       *
88       * @param script The script to run. This may be a {@link Script}, a {@link ScriptFile} or a {@link ScriptRef}. The
89       *            script must return a {@code List<PathWithAttributes>}. When the script is executed, it is provided the
90       *            following bindings:
91       *            <ul>
92       *            <li>basePath - the directory from where the {@link DeleteAction Delete} action started scanning for
93       *            files to delete. Can be used to relativize the paths in the pathList.</li>
94       *            <li>pathList - a {@code java.util.List} containing {@link PathWithAttribute} objects. (The script is
95       *            free to modify and return this list.)</li>
96       *            <li>substitutor - a {@link StrSubstitutor} that can be used to look up variables embedded in the base
97       *            dir or other properties
98       *            <li>statusLogger - the {@link StatusLogger} that can be used to log events during script execution
99       *            <li>any properties declared in the configuration</li>
100      *            </ul>
101      * @param configuration the configuration
102      * @return A ScriptCondition.
103      */
104     @PluginFactory
105     public static ScriptCondition createCondition(@PluginElement("Script") final AbstractScript script,
106             @PluginConfiguration final Configuration configuration) {
107 
108         if (script == null) {
109             LOGGER.error("A Script, ScriptFile or ScriptRef element must be provided for this ScriptCondition");
110             return null;
111         }
112         if (script instanceof ScriptRef) {
113             if (configuration.getScriptManager().getScript(script.getName()) == null) {
114                 LOGGER.error("ScriptCondition: No script with name {} has been declared.", script.getName());
115                 return null;
116             }
117         }
118         return new ScriptCondition(script, configuration);
119     }
120 }