EtlExecutor


1   /*
2    * Copyright 2006-2007 The Scriptella Project Team.
3    *
4    * Licensed under the Apache License, Version 2.0 (the "License");
5    * you may not use this file except in compliance with the License.
6    * You may obtain a copy of the License at
7    *
8    *      http://www.apache.org/licenses/LICENSE-2.0
9    *
10   * Unless required by applicable law or agreed to in writing, software
11   * distributed under the License is distributed on an "AS IS" BASIS,
12   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13   * See the License for the specific language governing permissions and
14   * limitations under the License.
15   */
16  package scriptella.execution;
17  
18  import scriptella.configuration.ConfigurationEl;
19  import scriptella.configuration.ConfigurationFactory;
20  import scriptella.core.Session;
21  import scriptella.core.ThreadSafe;
22  import scriptella.interactive.ProgressCallback;
23  import scriptella.interactive.ProgressIndicator;
24  import scriptella.util.CollectionUtils;
25  import scriptella.util.IOUtils;
26  
27  import java.io.File  ;
28  import java.net.MalformedURLException  ;
29  import java.net.URL  ;
30  import java.util.Map  ;
31  import java.util.logging.Level  ;
32  import java.util.logging.Logger  ;
33  
34  
35  /**
36   * Executor for ETL files.
37   * <p>Use {@link ConfigurationFactory} to parse script files and to configure
38   * the executor.
39   * <p>The usage scenario of this class may be described using the following steps:
40   * <ul>
41   * <li>{@link #EtlExecutor(scriptella.configuration.ConfigurationEl)} Create an instance of this class
42   * and pass a {@link scriptella.configuration.ConfigurationFactory#createConfiguration() script file configuration}.
43   * <li>{@link #execute() Execute} the script
44   * </ul>
45   * </pre></code>
46   * <p>Additionally simplified helper methods are declared in this class:
47   * <ul>
48   * <li>{@link #newExecutor(java.io.File)}
49   * <li>{@link #newExecutor(java.net.URL)}
50   * <li>{@link #newExecutor(java.net.URL, java.util.Map)}
51   * </ul>
52   * <p/>
53   * <h3>ETL Cancellation</h3>
54   * Scriptella execution model relies on a standard Java {@link Thread#interrupt()} mechanism.
55   * <p>To interrupt the ETL execution invoke {@link Thread#interrupt()} on a thread
56   * which {@link #execute() started} ETL operation. As a part of interruption process
57   * the engine tries to roll back all changes made during the ETL operation.
58   * <p>{@link java.util.concurrent.ExecutorService} and {@link java.util.concurrent.Future}
59   * can also be used to control ETL execution.
60   *
61   * @author Fyodor Kupolov
62   * @version 1.0
63   */
64  public class EtlExecutor {
65      private static final Logger   LOG = Logger.getLogger(EtlExecutor.class.getName());
66      private ConfigurationEl configuration;
67      private boolean jmxEnabled;
68  
69      /**
70       * Creates ETL executor.
71       */
72      public EtlExecutor() {
73      }
74  
75      /**
76       * Creates an ETL executor for specified configuration file.
77       *
78       * @param configuration ETL configuration.
79       */
80      public EtlExecutor(ConfigurationEl configuration) {
81          this.configuration = configuration;
82      }
83  
84      /**
85       * Returns ETL configuration for this executor.
86       *
87       * @return ETL configuration.
88       */
89      public ConfigurationEl getConfiguration() {
90          return configuration;
91      }
92  
93      /**
94       * Sets ETL configuration.
95       *
96       * @param configuration ETL configuration.
97       */
98      public void setConfiguration(final ConfigurationEl configuration) {
99          this.configuration = configuration;
100     }
101 
102 
103     /**
104      * Returns true if monitoring/management via JMX is enabled.
105      * <p>If jmxEnabled=true the executor registers MBeans for executed ETL files.
106      * The object names of the mbeans have the following form:
107      * <code>scriptella: type=etl,url="ETL_FILE_URL"</code>
108      *
109      * @return true if monitoring/management via JMX is enabled.
110      */
111     public boolean isJmxEnabled() {
112         return jmxEnabled;
113     }
114 
115     /**
116      * Enables or disables ETL monitoring/management via JMX.
117      * <p>If jmxEnabled=true the executor registers MBeans for executed ETL files.
118      * The object names of the mbeans have the following form:
119      * <code>scriptella: type=etl,url="ETL_FILE_URL"</code>
120      *
121      * @param jmxEnabled true if monitoring/management via JMX is enabled.
122      * @see scriptella.execution.JmxEtlManagerMBean
123      */
124     public void setJmxEnabled(boolean jmxEnabled) {
125         this.jmxEnabled = jmxEnabled;
126     }
127 
128     /**
129      * Executes ETL based on a specified configuration.
130      */
131     @ThreadSafe
132     public ExecutionStatistics execute() throws EtlExecutorException {
133         return execute((ProgressIndicator) null);
134     }
135 
136     /**
137      * Executes ETL based on a specified configuration.
138      *
139      * @param indicator progress indicator to use.
140      */
141     @ThreadSafe
142     public ExecutionStatistics execute(final ProgressIndicator indicator)
143             throws EtlExecutorException {
144         EtlContext ctx = null;
145         JmxEtlManager etlManager = null;
146 
147         try {
148             ctx = prepare(indicator);
149             if (jmxEnabled) {
150                 etlManager = new JmxEtlManager(ctx);
151                 etlManager.register();
152             }
153             execute(ctx);
154             ctx.getProgressCallback().step(5, "Commiting transactions");
155             commitAll(ctx);
156         } catch (Throwable   e) {
157             if (ctx != null) {
158                 rollbackAll(ctx);
159             }
160             throw new EtlExecutorException(e);
161         } finally {
162             if (ctx != null) {
163                 closeAll(ctx);
164                 ctx.getStatisticsBuilder().etlComplete();
165                 ctx.getProgressCallback().complete();
166             }
167             if (etlManager != null) {
168                 etlManager.unregister();
169             }
170         }
171 
172         return ctx.getStatisticsBuilder().getStatistics();
173     }
174 
175     void rollbackAll(final EtlContext ctx) {
176         try {
177             ctx.session.rollback();
178         } catch (Exception   e) {
179             LOG.log(Level.SEVERE, "Unable to rollback script", e);
180         }
181     }
182 
183     void commitAll(final EtlContext ctx) {
184         ctx.session.commit();
185     }
186 
187     void closeAll(final EtlContext ctx) {
188         ctx.session.close();
189     }
190 
191     private void execute(final EtlContext ctx) {
192         final ProgressCallback oldProgress = ctx.getProgressCallback();
193 
194         final ProgressCallback p = oldProgress.fork(85, 100);
195         final ProgressCallback p2 = p.fork(100);
196         ctx.setProgressCallback(p2);
197         ctx.session.execute(ctx);
198         p.complete();
199         ctx.setProgressCallback(oldProgress);
200     }
201 
202     /**
203      * Prepares the scripts context.
204      *
205      * @param indicator progress indicator to use.
206      * @return prepared scripts context.
207      */
208     protected EtlContext prepare(final ProgressIndicator indicator) {
209         EtlContext ctx = new EtlContext();
210         ctx.getStatisticsBuilder().etlStarted();
211         ctx.setBaseURL(configuration.getDocumentUrl());
212         ctx.setProgressCallback(new ProgressCallback(100, indicator));
213 
214         final ProgressCallback progress = ctx.getProgressCallback();
215         progress.step(1, "Initializing properties");
216         ctx.setProperties(configuration.getProperties());
217         ctx.setProgressCallback(progress.fork(9, 100));
218         ctx.session = new Session(configuration, ctx);
219         ctx.getProgressCallback().complete();
220         ctx.setProgressCallback(progress); //Restoring
221 
222         return ctx;
223     }
224 
225     /**
226      * Converts file to URL and invokes {@link #newExecutor(java.net.URL)}.
227      *
228      * @param scriptFile ETL file.
229      * @return configured instance of script executor.
230      * @see #newExecutor(java.net.URL)
231      */
232     public static EtlExecutor newExecutor(final File   scriptFile) {
233         try {
234             return newExecutor(IOUtils.toUrl(scriptFile));
235         } catch (MalformedURLException   e) {
236             throw new IllegalArgumentException  (e.getMessage(), e);
237         }
238     }
239 
240     /**
241      * Helper method to create a new ScriptExecutor for specified script URL.
242      * <p>Calls {@link #newExecutor(java.net.URL, java.util.Map)} and passes {@link System#getProperties() System properties}
243      * as external properties.
244      *
245      * @param scriptFileUrl URL of script file.
246      * @return configured instance of script executor.
247      */
248     @ThreadSafe
249     public static EtlExecutor newExecutor(final URL   scriptFileUrl) {
250         return newExecutor(scriptFileUrl, CollectionUtils.asMap(System.getProperties()));
251     }
252 
253     /**
254      * Helper method to create a new ScriptExecutor for specified script URL.
255      *
256      * @param scriptFileUrl      URL of script file.
257      * @param externalProperties see {@link ConfigurationFactory#setExternalProperties(java.util.Map)}
258      * @return configured instance of script executor.
259      * @see ConfigurationFactory
260      */
261     @ThreadSafe
262     public static EtlExecutor newExecutor(final URL   scriptFileUrl, final Map  <String  , ?> externalProperties) {
263         ConfigurationFactory cf = new ConfigurationFactory();
264         cf.setResourceURL(scriptFileUrl);
265         if (externalProperties != null) {
266             cf.setExternalProperties(externalProperties);
267         }
268         return new EtlExecutor(cf.createConfiguration());
269     }
270 
271 }
272
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