001 /**
002 * Licensed to the Apache Software Foundation (ASF) under one or more
003 * contributor license agreements. See the NOTICE file distributed with
004 * this work for additional information regarding copyright ownership.
005 * The ASF licenses this file to You under the Apache License, Version 2.0
006 * (the "License"); you may not use this file except in compliance with
007 * the License. You may obtain a copy of the License at
008 *
009 * http://www.apache.org/licenses/LICENSE-2.0
010 *
011 * Unless required by applicable law or agreed to in writing, software
012 * distributed under the License is distributed on an "AS IS" BASIS,
013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014 * See the License for the specific language governing permissions and
015 * limitations under the License.
016 */
017 package org.apache.camel.component.file;
018
019 import java.io.File;
020 import java.util.concurrent.locks.Lock;
021 import java.util.concurrent.locks.ReentrantLock;
022
023 import org.apache.camel.Exchange;
024 import org.apache.camel.Expression;
025 import org.apache.camel.impl.DefaultExchange;
026 import org.apache.camel.impl.DefaultProducer;
027 import org.apache.camel.util.FileUtil;
028 import org.apache.camel.util.LRUCache;
029 import org.apache.camel.util.ObjectHelper;
030 import org.apache.camel.util.ServiceHelper;
031 import org.apache.camel.util.StringHelper;
032 import org.slf4j.Logger;
033 import org.slf4j.LoggerFactory;
034
035 /**
036 * Generic file producer
037 */
038 public class GenericFileProducer<T> extends DefaultProducer {
039 protected final Logger log = LoggerFactory.getLogger(getClass());
040 protected final GenericFileEndpoint<T> endpoint;
041 protected GenericFileOperations<T> operations;
042 // assume writing to 100 different files concurrently at most for the same file producer
043 private final LRUCache<String, Lock> locks = new LRUCache<String, Lock>(100);
044
045 protected GenericFileProducer(GenericFileEndpoint<T> endpoint, GenericFileOperations<T> operations) {
046 super(endpoint);
047 this.endpoint = endpoint;
048 this.operations = operations;
049 }
050
051 public String getFileSeparator() {
052 return File.separator;
053 }
054
055 public String normalizePath(String name) {
056 return FileUtil.normalizePath(name);
057 }
058
059 public void process(Exchange exchange) throws Exception {
060 // store any existing file header which we want to keep and propagate
061 final String existing = exchange.getIn().getHeader(Exchange.FILE_NAME, String.class);
062
063 // create the target file name
064 String target = createFileName(exchange);
065
066 // use lock for same file name to avoid concurrent writes to the same file
067 // for example when you concurrently append to the same file
068 Lock lock;
069 synchronized (locks) {
070 lock = locks.get(target);
071 if (lock == null) {
072 lock = new ReentrantLock();
073 locks.put(target, lock);
074 }
075 }
076
077 lock.lock();
078 try {
079 processExchange(exchange, target);
080 } finally {
081 // do not remove as the locks cache has an upper bound
082 // this ensure the locks is appropriate reused
083 lock.unlock();
084 // and remove the write file name header as we only want to use it once (by design)
085 exchange.getIn().removeHeader(Exchange.OVERRULE_FILE_NAME);
086 // and restore existing file name
087 exchange.getIn().setHeader(Exchange.FILE_NAME, existing);
088 }
089 }
090
091 /**
092 * Sets the operations to be used.
093 * <p/>
094 * Can be used to set a fresh operations in case of recovery attempts
095 *
096 * @param operations the operations
097 */
098 public void setOperations(GenericFileOperations<T> operations) {
099 this.operations = operations;
100 }
101
102 /**
103 * Perform the work to process the fileExchange
104 *
105 * @param exchange fileExchange
106 * @param target the target filename
107 * @throws Exception is thrown if some error
108 */
109 protected void processExchange(Exchange exchange, String target) throws Exception {
110 log.trace("Processing file: {} for exchange: {}", target, exchange);
111
112 try {
113 preWriteCheck();
114
115 // should we write to a temporary name and then afterwards rename to real target
116 boolean writeAsTempAndRename = ObjectHelper.isNotEmpty(endpoint.getTempFileName());
117 String tempTarget = null;
118 // remember if target exists to avoid checking twice
119 Boolean targetExists = null;
120 if (writeAsTempAndRename) {
121 // compute temporary name with the temp prefix
122 tempTarget = createTempFileName(exchange, target);
123
124 log.trace("Writing using tempNameFile: {}", tempTarget);
125
126 //if we should eager delete target file before deploying temporary file
127 if (endpoint.getFileExist() != GenericFileExist.TryRename && endpoint.isEagerDeleteTargetFile()) {
128
129 // cater for file exists option on the real target as
130 // the file operations code will work on the temp file
131
132 // if an existing file already exists what should we do?
133 targetExists = operations.existsFile(target);
134 if (targetExists) {
135
136 log.trace("EagerDeleteTargetFile, target exists");
137
138 if (endpoint.getFileExist() == GenericFileExist.Ignore) {
139 // ignore but indicate that the file was written
140 log.trace("An existing file already exists: {}. Ignore and do not override it.", target);
141 return;
142 } else if (endpoint.getFileExist() == GenericFileExist.Fail) {
143 throw new GenericFileOperationFailedException("File already exist: " + target + ". Cannot write new file.");
144 } else if (endpoint.isEagerDeleteTargetFile() && endpoint.getFileExist() == GenericFileExist.Override) {
145 // we override the target so we do this by deleting it so the temp file can be renamed later
146 // with success as the existing target file have been deleted
147 log.trace("Eagerly deleting existing file: {}", target);
148 if (!operations.deleteFile(target)) {
149 throw new GenericFileOperationFailedException("Cannot delete file: " + target);
150 }
151 }
152 }
153 }
154
155 // delete any pre existing temp file
156 if (operations.existsFile(tempTarget)) {
157 log.trace("Deleting existing temp file: {}", tempTarget);
158 if (!operations.deleteFile(tempTarget)) {
159 throw new GenericFileOperationFailedException("Cannot delete file: " + tempTarget);
160 }
161 }
162 }
163
164 // write/upload the file
165 writeFile(exchange, tempTarget != null ? tempTarget : target);
166
167 // if we did write to a temporary name then rename it to the real
168 // name after we have written the file
169 if (tempTarget != null) {
170 // if we did not eager delete the target file
171 if (endpoint.getFileExist() != GenericFileExist.TryRename && !endpoint.isEagerDeleteTargetFile()) {
172
173 // if an existing file already exists what should we do?
174 targetExists = operations.existsFile(target);
175 if (targetExists) {
176
177 log.trace("Not using EagerDeleteTargetFile, target exists");
178
179 if (endpoint.getFileExist() == GenericFileExist.Ignore) {
180 // ignore but indicate that the file was written
181 log.trace("An existing file already exists: {}. Ignore and do not override it.", target);
182 return;
183 } else if (endpoint.getFileExist() == GenericFileExist.Fail) {
184 throw new GenericFileOperationFailedException("File already exist: " + target + ". Cannot write new file.");
185 } else if (endpoint.getFileExist() == GenericFileExist.Override) {
186 // we override the target so we do this by deleting it so the temp file can be renamed later
187 // with success as the existing target file have been deleted
188 log.trace("Deleting existing file: {}", target);
189 if (!operations.deleteFile(target)) {
190 throw new GenericFileOperationFailedException("Cannot delete file: " + target);
191 }
192 }
193 }
194 }
195
196 // now we are ready to rename the temp file to the target file
197 log.trace("Renaming file: [{}] to: [{}]", tempTarget, target);
198 boolean renamed = operations.renameFile(tempTarget, target);
199 if (!renamed) {
200 throw new GenericFileOperationFailedException("Cannot rename file from: " + tempTarget + " to: " + target);
201 }
202 }
203
204 // any done file to write?
205 if (endpoint.getDoneFileName() != null) {
206 String doneFileName = endpoint.createDoneFileName(target);
207 ObjectHelper.notEmpty(doneFileName, "doneFileName", endpoint);
208
209 // create empty exchange with empty body to write as the done file
210 Exchange empty = new DefaultExchange(exchange);
211 empty.getIn().setBody("");
212
213 log.trace("Writing done file: [{}]", doneFileName);
214 // delete any existing done file
215 if (operations.existsFile(doneFileName)) {
216 if (!operations.deleteFile(doneFileName)) {
217 throw new GenericFileOperationFailedException("Cannot delete existing done file: " + doneFileName);
218 }
219 }
220 writeFile(empty, doneFileName);
221 }
222
223 // let's store the name we really used in the header, so end-users
224 // can retrieve it
225 exchange.getIn().setHeader(Exchange.FILE_NAME_PRODUCED, target);
226 } catch (Exception e) {
227 handleFailedWrite(exchange, e);
228 }
229
230 postWriteCheck();
231 }
232
233 /**
234 * If we fail writing out a file, we will call this method. This hook is
235 * provided to disconnect from servers or clean up files we created (if needed).
236 */
237 public void handleFailedWrite(Exchange exchange, Exception exception) throws Exception {
238 throw exception;
239 }
240
241 /**
242 * Perform any actions that need to occur before we write such as connecting to an FTP server etc.
243 */
244 public void preWriteCheck() throws Exception {
245 // nothing needed to check
246 }
247
248 /**
249 * Perform any actions that need to occur after we are done such as disconnecting.
250 */
251 public void postWriteCheck() {
252 // nothing needed to check
253 }
254
255 public void writeFile(Exchange exchange, String fileName) throws GenericFileOperationFailedException {
256 // build directory if auto create is enabled
257 if (endpoint.isAutoCreate()) {
258 // we must normalize it (to avoid having both \ and / in the name which confuses java.io.File)
259 String name = FileUtil.normalizePath(fileName);
260
261 // use java.io.File to compute the file path
262 File file = new File(name);
263 String directory = file.getParent();
264 boolean absolute = FileUtil.isAbsolute(file);
265 if (directory != null) {
266 if (!operations.buildDirectory(directory, absolute)) {
267 log.debug("Cannot build directory [{}] (could be because of denied permissions)", directory);
268 }
269 }
270 }
271
272 // upload
273 if (log.isTraceEnabled()) {
274 log.trace("About to write [{}] to [{}] from exchange [{}]", new Object[]{fileName, getEndpoint(), exchange});
275 }
276
277 boolean success = operations.storeFile(fileName, exchange);
278 if (!success) {
279 throw new GenericFileOperationFailedException("Error writing file [" + fileName + "]");
280 }
281 log.debug("Wrote [{}] to [{}]", fileName, getEndpoint());
282 }
283
284 public String createFileName(Exchange exchange) {
285 String answer;
286
287 // overrule takes precedence
288 Object value;
289
290 Object overrule = exchange.getIn().getHeader(Exchange.OVERRULE_FILE_NAME);
291 if (overrule != null) {
292 if (overrule instanceof Expression) {
293 value = overrule;
294 } else {
295 value = exchange.getContext().getTypeConverter().convertTo(String.class, exchange, overrule);
296 }
297 } else {
298 value = exchange.getIn().getHeader(Exchange.FILE_NAME);
299 }
300
301 // if we have an overrule then override the existing header to use the overrule computed name from this point forward
302 if (overrule != null) {
303 exchange.getIn().setHeader(Exchange.FILE_NAME, value);
304 }
305
306 if (value != null && value instanceof String && StringHelper.hasStartToken((String) value, "simple")) {
307 log.warn("Simple expression: {} detected in header: {} of type String. This feature has been removed (see CAMEL-6748).", value, Exchange.FILE_NAME);
308 }
309
310 // expression support
311 Expression expression = endpoint.getFileName();
312 if (value != null && value instanceof Expression) {
313 expression = (Expression) value;
314 }
315
316 // evaluate the name as a String from the value
317 String name;
318 if (expression != null) {
319 log.trace("Filename evaluated as expression: {}", expression);
320 name = expression.evaluate(exchange, String.class);
321 } else {
322 name = exchange.getContext().getTypeConverter().convertTo(String.class, exchange, value);
323 }
324
325 // flatten name
326 if (name != null && endpoint.isFlatten()) {
327 // check for both windows and unix separators
328 int pos = Math.max(name.lastIndexOf("/"), name.lastIndexOf("\\"));
329 if (pos != -1) {
330 name = name.substring(pos + 1);
331 }
332 }
333
334 // compute path by adding endpoint starting directory
335 String endpointPath = endpoint.getConfiguration().getDirectory();
336 String baseDir = "";
337 if (endpointPath.length() > 0) {
338 // Its a directory so we should use it as a base path for the filename
339 // If the path isn't empty, we need to add a trailing / if it isn't already there
340 baseDir = endpointPath;
341 boolean trailingSlash = endpointPath.endsWith("/") || endpointPath.endsWith("\\");
342 if (!trailingSlash) {
343 baseDir += getFileSeparator();
344 }
345 }
346 if (name != null) {
347 answer = baseDir + name;
348 } else {
349 // use a generated filename if no name provided
350 answer = baseDir + endpoint.getGeneratedFileName(exchange.getIn());
351 }
352
353 if (endpoint.getConfiguration().needToNormalize()) {
354 // must normalize path to cater for Windows and other OS
355 answer = normalizePath(answer);
356 }
357
358 return answer;
359 }
360
361 public String createTempFileName(Exchange exchange, String fileName) {
362 String answer = fileName;
363
364 String tempName;
365 if (exchange.getIn().getHeader(Exchange.FILE_NAME) == null) {
366 // its a generated filename then add it to header so we can evaluate the expression
367 exchange.getIn().setHeader(Exchange.FILE_NAME, FileUtil.stripPath(fileName));
368 tempName = endpoint.getTempFileName().evaluate(exchange, String.class);
369 // and remove it again after evaluation
370 exchange.getIn().removeHeader(Exchange.FILE_NAME);
371 } else {
372 tempName = endpoint.getTempFileName().evaluate(exchange, String.class);
373 }
374
375 // check for both windows and unix separators
376 int pos = Math.max(answer.lastIndexOf("/"), answer.lastIndexOf("\\"));
377 if (pos == -1) {
378 // no path so use temp name as calculated
379 answer = tempName;
380 } else {
381 // path should be prefixed before the temp name
382 StringBuilder sb = new StringBuilder(answer.substring(0, pos + 1));
383 sb.append(tempName);
384 answer = sb.toString();
385 }
386
387 if (endpoint.getConfiguration().needToNormalize()) {
388 // must normalize path to cater for Windows and other OS
389 answer = normalizePath(answer);
390 }
391
392 return answer;
393 }
394
395 @Override
396 protected void doStart() throws Exception {
397 super.doStart();
398 ServiceHelper.startService(locks);
399 }
400
401 @Override
402 protected void doStop() throws Exception {
403 ServiceHelper.stopService(locks);
404 super.doStop();
405 }
406 }