[CONF] Apache Camel > Why does my file consumer not pick up the file, and how do I let the file consumer use the Camel error handler?

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Why does my file consumer not pick up the file, and how do I let the file consumer use the Camel error handler? Page edited by Reuben Garrett Comment: minor editorial changes Changes (9) h2. Why does my file consumer not pick up the file, and how do I let the file consumer use the Camel error handler? There could be several reasons why the [File|File2] consumer is not picking up files. For example it may not run at all, or it cannot acquire a read lock on the file. Check the logs to see if you can see any exceptions / messages being logged. You can turn on DEBUG logging at {{org.apache.camel.component.file}} to see more details. [Check the logs|Logging questions] for any exceptions or other informative messages. You can [turn on DEBUG logging|How do I enable debug logging] at {{org.apache.camel.component.file}} to see more detail. h3. How to use the Camel's routing error handlers with the file consumer Well this is really a chicken and egg questions. The Camel [error handler|Error handling in Camel] (eg in the routes) does only apply when a message is being routed by the routing engine. Before this happens a consumer must successfully receive a message, and created a Camel [Exchange], and populate the [Exchange] with message details (eg body and headers), and then pass the [Exchange] to the routing engine. Only at this point the routing error handler can deal with exceptions occurring. Before this point, any error handling is really [Component] specific. Well, this is really a "[chicken or the egg|http://en.wikipedia.org/wiki/Chicken_or_the_egg]" question. The Camel [error handler|Error handling in Camel] (e.g., in the routes) only applies when a message is being routed by the routing engine. Before this happens, a consumer must successfully receive a message, create a Camel [Exchange], populate the [Exchange] with message details (e.g., body and headers), and then pass the [Exchange] to the routing engine. Only at this point can the routing error handler deal with exceptions occurring. Before this point, any error handling is really [Component]-specific. If the component consumer extends the {{DefaultConsumer}} from Camel, then this consumer offers a {{org.apache.camel.spi.ExceptionHandler}} the component can use to allow a hook for end users to plugin their custom implementation. The default implementation from Camel is {{LoggingExceptionHandler}} that will log the exception at ERROR/WARN level, and then ignore the exception. If the component consumer extends the [{{DefaultConsumer}}|http://svn.apache.org/viewvc/camel/trunk/camel-core/src/main/java/org/apache/camel/impl/DefaultConsumer.java?view=markup] from Camel, then it offers an [{{org.apache.camel.spi.ExceptionHandler}}|http://svn.apache.org/viewvc/camel/trunk/camel-core/src/main/java/org/apache/camel/spi/ExceptionHandler.java?view=markup] hook for end users to plug-in a custom strategy. The default implementation from Camel is [{{LoggingExceptionHandler}}|http://svn.apache.org/viewvc/camel/trunk/camel-core/src/main/java/org/apache/camel/impl/LoggingExceptionHandler.java?view=markup] that will log the exception at {{ERROR}}/{{WARN}} level, and then ignore the exception. See the [File|File2] page in the bottom for an example how to use a custom {{ExceptionHandler}} that sends a new message to the Camel routing engine, that which then allows the routing engine to trigger its own error handling to deal with the exception. Full Content Why does my file consumer not pick up the file, and how do I let the file consumer use the Camel error handler? There could be several reasons why the File consumer is not picking up files. For example it may not run at all, or it cannot acquire a read lock on the file. Check the logs for any exceptions or other informative messages. You can turn on DEBUG logging at org.apache.camel.component.file to see more detail. How to use Camel's routing error handlers with the file consumer Well, this is really a "chicken or the egg" question. The Camel error handler (e.g., in the routes) only applies when a message is being routed by the routing engine. Before this happens, a consumer must successfully receive a message, create a Camel Exchange, populate the Exchange with message details (e.g., body and headers), and then pass the Exchange to the routing engine. Only at this point can the routing error handler deal with exceptions occurring. Before this point, any error handling is really Component-specific. If the component consumer extends the DefaultConsumer from Camel, then it offers an org.apache.camel.spi.ExceptionHandler hook for end users to plug-in a custom strategy. The default implementation from Camel is LoggingExceptionHandler that will log the exception at ERROR/WARN level, and then ignore the exception. See the File page in the bottom for an example how to use a custom ExceptionHandler that sends a new message to the Camel routing engine, which then allows the routing engine to trigger its own error handling to deal with the exception. Change Notification Preferences View Online | View Changes | Add Comment