The File component provides access to file systems; allowing files to be processed by any other FUSE Mediation Router Components or messages from other components can be saved to disk.
file:directoryName[?options]
or
file://directoryName[?options]
Where directoryName represents the underlying file directory.
![]() | Only directories |
---|---|
FUSE Mediation Router 2.0 only support endpoints configured with a starting
directory. So the directoryName must be a
directory. If you want to consume a single file only, you can use the fileName option to only select your filename, e.g. by
just setting In FUSE Mediation Router 1.x you could also configure a file and this caused more harm than good as it could lead to confusing situations. |
Name | Default Value | Description |
---|---|---|
autoCreate | true | If set to true FUSE Mediation Router will create the directory to the file if the file path does not exists. |
bufferSize | 128kb | Write buffer sized in bytes. |
fileName | null | Use Expression such as File
Language to dynamically set the filename. For consumers its used as
a filename filter. For producers its used to evaluate the filename to write. If
an expression is set it take precedents over the
CamelFileName header. (Note: The header itself can also be an Expression). The expression options supports both String and
Expression types. If the expression is a String type then its always evaluated using the File
Language. If the expression is an Expression type then this type is
of course used as it - this allows for instance also to use OGNL as expression. For the consumer, you can use it to filter
filenames, so you can for instance consume todays file using the File Language syntax:
{{mydata-$\{date:now:yyyyMMdd}.txt}}. |
flattern | false | Flattern is used to flattern the file name path to strip any leading paths, so
its just the file name. This allows you to consume recursive into sub
directories but when you eg write the files to another directory they will be
written in a single directory. Setting this to true on the producer enforces
that any file name recived in CamelFileName header will be
stripped for any leading paths. |
Name | Default Value | Description |
---|---|---|
initialDelay | 1000 | milliseconds before polling the file/directory starts |
delay | 500 | milliseconds before the next poll of the file/directory |
useFixedDelay | false | true to use fixed delay between pools, otherwise fixed rate is used. See ScheduledExecutorService in JDK for details. |
recursive | false | if a directory, will look for files in all the sub directories as well. |
delete | false | If delete is true then the file will be deleted after it is processed |
noop | false | If true then the file is not moved or deleted in any way. This option is good for read only data, or for ETL type requirements. If noop=true then Camel will set idempotent=true as well, avoiding consuming the same files over and over again. |
preMove | null | Use Expression such as File
Language to dynamically set the filename when moving it before processing. For example to move in progress
file into the order directory set this value to
order
|
move | .camel | Use Expression such as File
Language to dynamically set the filename when moving it after processing. To move files into a .done
subdirectory just enter .done . |
include | null | Is used to include files if filename matches the regex pattern. |
exclude | null | Is used to exclude files if filename matches the regex pattern. |
idempotent | false | Option to use the Idempotent Consumer EIP pattern to let Camel skip already processed files. Will default use a memory based LRUCache that holds 1000 entries. If noop=true then idempotent will be enabled as well to avoid consuming the same files over and over again. |
idempotentRepository | null | Pluggable repository as a org.apache.camel.processor.idempotent.MessageIdRepository class. Will default use MemoryMessageIdRepository if none is specified and idempotent is true. |
filter | null | Pluggable filter as a
org.apache.camel.component.file.GenericFileFilter class.
Will skip files if filter returns false in its accept method. Camel also ships
with an ANT path matcher filter in the
camel-spring component. More details in section below. |
sorter | null | Pluggable sorter as a java.util.Comparator class. |
sortBy | null | Build in sort by using the File Language. Supports nested sorts so you can have a sort by file name and as a 2nd group sort by modified date. See sorting section below for details. |
readLock | markerFile | Used by consumer, to only poll the files if it has exclusive read lock to the
file (= the file is not in progress of being written). Camel will wait until the
file lock is granted. This option provides the build in strategies: fileLock, rename,
markerFile and none. fileLock is for using
java.nio.channels.FileLock . rename is for using a try to
rename the file as a test if we can get exclusive read lock. markerFile is the behaviour from FUSE Mediation
Router 1.x, where FUSE Mediation Router will create a marker file and hold lock
on the marker file. none is for no read locks
at all. |
readLockTimeout | 0 | Optional timeout in millis for the read lock, if supported by the read lock. If the read lock could not be granted and the timeout triggered then FUSE Mediation Router will skip the file. At next poll FUSE Mediation Router will try the file again, and this time maybe the read lock could be granted. |
exclusiveReadLockStrategy | null | Pluggable read lock as a
org.apache.camel.component.file.GenericFileExclusiveReadLockStrategy
implementation. |
Name | Default Value | Description |
---|---|---|
append | true | When writing do we append to the end of the file, or replace it? |
tempPrefix | null | This option is used to write the file using a temporary name, and then after the write is complete rename it to the real name. Can be used to identify files being written and also avoid consumers (not using exclusive read locks) reading in progress files. Is often used by FTP when uploading big files. |
By default the file is locked for the duration of the processing.
After the route has completed they are moved into the .camel subdirectory; so that they appear to be deleted.
The File Consumer will always skip any file which name starts with a dot, such
as ".", ".camel", ".m2" or ".groovy"
.
Only files (not directories) is matched for valid filename if options such as:
includeNamePrefix, includeNamePostfix, excludeNamePrefix,
excludeNamePostfix, regexPattern
is used.
Any move or delete operations is executed after (post command) the routing has completed; so during processing of the Exchange the file is still located in the inbox folder.
Lets illustrate this with an example:
from("file://inobox?move=.done").to("bean:handleOrder");
When a file is dropped in the inbox folder the file consumer notices this and creates
a new FileExchange
that is routed to the handleOrder bean. The bean
then processes the File. At this point in time the File is still located in the inbox
folder. After the bean completes and thus the route is completed the file consumer will
perform the move operation and move the file to the .done sub folder.
The move and preMove option should be a directory name. It can be either relative or absolute. If relative the directory is created as a sub folder from within the folder where the file was consumed.
By default FUSE Mediation Router will move consumed files to the sub folder
.camel
relative where the file was consumed.
If you want to delete the file after processing, then the route should be:
from("file://inobox?delete=true").to("bean:handleOrder");
We have introduced a pre move operation to move files before they are processed. This allows you to mark which files has been scanned as they are moved to this sub folder before being processed.
from("file://inobox?preMove=inprogress").to("bean:handleOrder");
You can combine the pre move and the regular move:
from("file://inobox?preMove=inprogress&move=.done").to("bean:handleOrder");
So in this situation the file is in the inprogress folder when being processed, and after it's processed it's moved to the .done folder.
The move and preMove
option is Expression based so we have the full power of the
File Language to do advanced configuration of the
directory and name pattern. FUSE Mediation Router will in fact internally convert the
directory name you enter into a File Language expression. So
when we enter move=.done
FUSE Mediation Router will convert this
into: {{$\{file:parent}/.done/$\{file:onlyname}}}. This is only done if FUSE Mediation Router detects that
you have not provided a ${ } in the option value yourself. So when you enter a ${ } FUSE
Mediation Router will not convert it and thus you have
the full power.
So if we want to move the file into a backup folder with todays date as the pattern we can do:
move=backup/${date:now:yyyyMMdd}/${file:name}
See more examples at File Language
Header | Description |
---|---|
CamelFileName | Specifies the name of the file to write (relative to the endpoint directory). The name can be a String, a String with a File Language or Simple expression. Or an Expression object. If its null then FUSE Mediation Router will auto generate a filename based on the message unique id. |
Header | Description |
---|---|
CamelFileName | Name of the consumed file as a relative file path with offset from the starting directory configured on the endpoint. |
CamelFileNameOnly | Only the file name, is just the name with no leading paths. |
CamelFileNameProduced | The actual absolute filepath (path + name) for the output file that was written. This header is set by Camel and its purpose is providing end-users the name of the file that was written. |
CamelFileAbsolute | A boolean whether the consumed file denotes a absolute path or not. Should normally be false for relative paths. Absolute path should normally not be used but we added to the move option to allow moving files to absolute paths. But can be used elsewhere as well. |
CamelFileAbsolutePath | The absolute path to the file. For relative files this path holds the relative path instead. |
CamelFilePath | The file path. For relative files this is the starting directory + the relative filename. For absolute files this is the absolute path. |
CamelFileRelativePath | The relative path. |
CamelFileParent | The parent path. |
CamelFileLength | A long containing the file size |
CamelFileLastModified | A Date containing the last modified timestamp of the file. |
CamelFileBatchSize | Total number of files being consumed in this batch. |
CamelFileBatchIndex | Current index out of total number of files being consumed in this batch. |
When FUSE Mediation Router is producing files (writing files) there are a few gotchas
how to set a filename of your choice. By default FUSE Mediation Router will use the
message id as the filename, and since the message id is normally a unique generated id
you will end up with filenames such as: ID-MACHINENAME-2443-1211718892437-1-0. If such a
filename is not desired, then a filename must be provided in the message header
"CamelFileName"
. The constant
Exchange.FILE_NAME
can also be used.
The sample code below produces files using the message id as the filename:
from("direct:report").to("file:target/reports");
To use report.txt as the filename you have to do:
from("direct:report").setHeader(Exchange.FILE_NAME, constant("report.txt")).to( "file:target/reports");
... the same as above, but with "CamelFileName":
from("direct:report").setHeader("CamelFileName", constant("report.txt")).to( "file:target/reports");
And a syntax where we set the filename on the endpoint with the fileName URI option.
from("direct:report").to("file:target/reports/?fileName=report.txt");
Filename can be set either using the expression
option or as a string based File Language expression in the
CamelFileName
header. See the File
Language for syntax and samples.
from("file://inputdir/?delete=true").to("file://outputdir")
Listen on a directory and create a message for each file dropped there. Copy the contents to the outputdir and delete the file in the inputdir.
from("file://inputdir/?recursive=true&delete=true").to("file://outputdir")
Listen on a directory and create a message for each file dropped there. Copy the contents to the outputdir and delete the file in the inputdir. Will scan recursive into sub directories. Will layout the files in the same directory structure in the outputdir as the inputdir, incl. any sub directory.
inputdir/foo.txt inputdir/sub/bar.txt
Will result to a layout as:
outputdir/foo.txt outputdir/sub/bar.txt
If you want to store the files in the outout directory in the same directory, eg to flattern out the path, then you just add the flatter=true option:
from("file://inputdir/?recursive=true&delete=true").to("file://outputdir?flattern=true")
Will result to a layout as:
outputdir/foo.txt outputdir/bar.txt
FUSE Mediation Router will by default move any processed file into a .camel subdirectory in the dir the file was consumed from.
from("file://inputdir/?recursive=true&delete=true").to("file://outputdir")
Will result in a layout as: before
inputdir/foo.txt inputdir/sub/bar.txt
after
inputdir/.camel/foo.txt inputdir/sub/.camel/bar.txt outputdir/foo.txt outputdir/sub/bar.txt
from("file://inputdir/").process(new Processor() { public void process(Exchange exchange) throws Exception { Object body = exchange.getIn().getBody(); // do some business logic with the input body } });
Body will be File object pointing to the file that was just dropped to the inputdir directory.
from("file://inputdir/").convertBodyTo(String.class).to("jms:test.queue")
By default the file endpoint sends a FileMessage which contains a File as body. If you send this directly to the jms component the jms message will only contain the File object but not the content. By converting the File to a String the message will contain the file contents what is probably what you want to do.
The route above using Spring DSL:
<route> <from uri="file://inputdir/"/> <convertBodyTo type="java.lang.String"/> <to uri="jms:test.queue"/> </route>
FUSE Mediation Router is of course also able to write files, eg. producing files. In the sample below we receive some reports on the SEDA queue that we processes before they are written to a directory.
public void testToFile() throws Exception { MockEndpoint mock = getMockEndpoint("mock:result"); mock.expectedMessageCount(1); mock.expectedFileExists("target/test-reports/report.txt"); template.sendBody("seda:reports", "This is a great report"); assertMockEndpointsSatisfied(); } protected JndiRegistry createRegistry() throws Exception { // bind our processor in the registry with the given id JndiRegistry reg = super.createRegistry(); reg.bind("processReport", new ProcessReport()); return reg; } protected RouteBuilder createRouteBuilder() throws Exception { return new RouteBuilder() { public void configure() throws Exception { // the reports from the seda queue is processed by our processor // before they are written to files in the target/reports directory from("seda:reports").processRef("processReport").to("file://target/test-reports", "mock:result"); } }; } private class ProcessReport implements Processor { public void process(Exchange exchange) throws Exception { String body = exchange.getIn().getBody(String.class); // do some business logic here // set the output to the file exchange.getOut().setBody(body); // set the output filename using java code logic, notice that this is done by setting // a special header property of the out exchange exchange.getOut().setHeader(Exchange.FILE_NAME, "report.txt"); } }
Using a single route, it is possible to write a file to any number of subdirectories. If you have a route setup as such:
<route> <from uri="bean:myBean"/> <to uri="file:/rootDirectory"/> </route>
You can have myBean
set the header
Exchange.FILE_NAME
to values such as:
Exchange.FILE_NAME = hello.txt => /rootDirectory/hello.txt Exchange.FILE_NAME = foo/bye.txt => /rootDirectory/foo/bye.txt
This allows you to have a single route to write files to multiple destinations.
In this sample we want to move consumed files to a backup folder using todays date as a sub foldername:
from("file://inbox?move=backup/${date:now:yyyyMMdd}/${file:name}").to("...");
See File Language for more samples.
FUSE Mediation Router supports Idempotent Consumer
directly within the component so it will skip already processed files. This feature can
be enabled by setting the idempotent=true
option.
from("file://inbox?idempotent=true").to("...");
By default FUSE Mediation Router uses a in memory based store for keeping track of
consumed files, it uses a least recently used cache storing holding up to 1000 entries.
You can plugin your own implementation of this store by using the
idempotentRepository
option using the # sign in the value to
indicate it's a referring to a bean in the Registry with
this id.
<!-- define our store as a plain spring bean --> <bean id="myStore" class="com.mycompany.MyIdempotentStore"/> <route> <from uri="file://inbox?idempotent=true&idempotentRepository=#myStore"/> <to uri="bean:processInbox"/> </route>
FUSE Mediation Router will log at DEBUG
level if it skips a file
because it has been consumed before:
DEBUG FileConsumer is idempotent and the file has been consumed before. Will skip this file: target\idempotent\report.txt
In this section we will use the file based idempotent repository
org.apache.camel.processor.idempotent.FileIdempotentRepository
instead of the in memory based that is used as default. This repository uses a 1st level
cache to avoid reading the file repository. It will only use the file repository to
store the content of the 1st level cache. Thereby the repository can survive server
restarts. It will load the content of the file into the 1st level cache upon startup.
The file structure is very simple as it store the key in separate lines in the file. By
default the file store has a size limit of 1mb when the file grew larger FUSE Mediation
Router will truncate the file store be rebuilding the content by flushing the 1st level
cache in a fresh empty file.
We configure our repository using Spring XML creating our file idempotent repository
and define our file consumer to use our repository with the
idempotentRepository
using # sign to indicate Registry lookup:
<!-- this is our file based idempotent store configured to use the .filestore.dat as file --> <bean id="fileStore" class="org.apache.camel.processor.idempotent.FileIdempotentRepository"> <!-- the filename for the store --> <property name="fileStore" value="target/fileidempotent/.filestore.dat"/> <!-- the max filesize in bytes for the file. Camel will trunk and flush the cache if the file gets bigger --> <property name="maxFileStoreSize" value="512000"/> <!-- the number of elements in our store --> <property name="cacheSize" value="250"/> </bean> <camelContext id="camel" xmlns="http://camel.apache.org/schema/spring"> <route> <from uri="file://target/fileidempotent/?idempotent=true&idempotentRepository=#fileStore&move=done/${file:name}"/> <to uri="mock:result"/> </route> </camelContext>
In this section we will use the JPA based idempotent repository instead of the in memory based that is used as default.
First we need a persistence-unit in META-INF/persistence.xml
where
we need to use the class
org.apache.camel.processor.idempotent.jpa.MessageProcessed
as
model.
<persistence-unit name="idempotentDb" transaction-type="RESOURCE_LOCAL"> <class>org.apache.camel.processor.idempotent.jpa.MessageProcessed</class> <properties> <property name="openjpa.ConnectionURL" value="jdbc:derby:target/idempotentTest;create=true"/> <property name="openjpa.ConnectionDriverName" value="org.apache.derby.jdbc.EmbeddedDriver"/> <property name="openjpa.jdbc.SynchronizeMappings" value="buildSchema"/> <property name="openjpa.Log" value="DefaultLevel=WARN, Tool=INFO"/> </properties> </persistence-unit>
Then we need to setup a Spring jpaTemplate in the spring XML file:
<!-- this is standard spring JPA configuration --> <bean id="jpaTemplate" class="org.springframework.orm.jpa.JpaTemplate"> <property name="entityManagerFactory" ref="entityManagerFactory"/> </bean> <bean id="entityManagerFactory" class="org.springframework.orm.jpa.LocalEntityManagerFactoryBean"> <!-- we use idempotentDB as the persitence unit name defined in the persistence.xml file --> <property name="persistenceUnitName" value="idempotentDb"/> </bean>
And finally we can create our JPA idempotent repository in the spring XML file as well:
<!-- we define our jpa based idempotent repository we want to use in the file consumer --> <bean id="jpaStore" class="org.apache.camel.processor.idempotent.jpa.JpaMessageIdRepository"> <!-- Here we refer to the spring jpaTemplate --> <constructor-arg index="0" ref="jpaTemplate"/> <!-- This 2nd parameter is the name (= a cateogry name). You can have different repositories with different names --> <constructor-arg index="1" value="FileConsumer"/> </bean>
And yes then we just need to refer to the jpaStore bean in the file consumer endpoint using the \[\[idempotentRepository}} using the # syntax option:
<route> <from uri="file://inbox?idempotent=true&idempotentRepository=#jpaStore"/> <to uri="bean:processInbox"/> </route>
FUSE Mediation Router supports pluggable filtering strategies. You can then configure the endpoint with such a filter to skip certain files being processed.
In the sample we have build our own filter that skips files starting with skip in the filename:
public class MyFileFilter implements GenericFileFilter { public boolean accept(GenericFile pathname) { // we dont accept any files starting with skip in the name return !pathname.getFileName().startsWith("skip"); } }
And then we can configure our route using the filter attribute to reference our filter (using # notation) that we have defines in the spring XML file:
<!-- define our sorter as a plain spring bean --> <bean id="myFilter" class="com.mycompany.MyFileSorter"/> <route> <from uri="file://inbox?filter=#myFilter"/> <to uri="bean:processInbox"/> </route>
The ANT path matcher is shipped out-of-the-box in the camel-spring jar. So you need to depend on camel-spring if you are using Maven. The reasons is that we leverage Spring's AntPathMatcher to do the actual matching.
The file paths is matched with the following rules:
?
matches one character
\*
matches zero or more characters
\*\*
matches zero or more directories in a path
The sample below demonstrates how to use it:
<camelContext xmlns="http://camel.apache.org/schema/spring"> <template id="camelTemplate"/> <!-- use myFilter as filter to allow setting ANT paths for which files to scan for --> <endpoint id="myFileEndpoint" uri="file://target/antpathmatcher?recursive=true&filter=#myAntFilter"/> <route> <from ref="myFileEndpoint"/> <to uri="mock:result"/> </route> </camelContext> <!-- we use the antpath file filter to use ant paths for includes and exlucde --> <bean id="myAntFilter" class="org.apache.camel.component.file.AntPathMatcherGenericFileFilter"> <!-- include and file in the subfolder that has day in the name --> <property name="includes" value="**/subfolder/**/*day*"/> <!-- exclude all files with bad in name or .xml files. Use comma to seperate multiple excludes --> <property name="excludes" value="**/*bad*,**/*.xml"/> </bean>
FUSE Mediation Router supports pluggable sorting strategies. This strategy it to use the build in java.util.Comparator in Java. You can then configure the endpoint with such a comparator and have FUSE Mediation Router sort the files before being processed.
In the sample we have build our own comparator that just sorts by file name:
public class MyFileSorter implements Comparator<GenericFile> { public int compare(GenericFile o1, GenericFile o2) { return o1.getFileName().compareTo(o2.getFileName()); } }
And then we can configure our route using the sorter option to reference to our sorter (mySorter) we have defined in the spring XML file:
<!-- define our sorter as a plain spring bean --> <bean id="mySorter" class="com.mycompany.MyFileSorter"/> <route> <from uri="file://inbox?sorter=#mySorter"/> <to uri="bean:processInbox"/> </route>
![]() | URI options can reference beans using the # syntax |
---|---|
In the Spring DSL route about notice that we can refer to beans in the Registry by prefixing the id with #. So writing
|
FUSE Mediation Router supports pluggable sorting strategies. This strategy it to use the File Language to configure the sorting. The sortBy is configured as:
sortBy=group 1;group 2;group 3;...
Where each group is separated with semi colon. In the simple situations you just use one group, so a simple example could be:
sortBy=file:name
This will sort by file name, you can reverse the order by prefixing
reverse:
to the group, so the sorting is now Z..A:
sortBy=reverse:file:name
As we have the full power of File Language we can use some of the other parameters, so if we want to sort by file size we do:
sortBy=file:size
You can configure to ignore the case, using ignoreCase:
for string
comparison, so if you want to use file name sorting but to ignore the case then we
do:
sortBy=ignoreCase:file:name
You can combine ignore case and reverse, however reverse must be specified first:
sortBy=reverse:ignoreCase:file:name
In the sample below we want to sort by last modified file, so we do:
sortBy=file:modifed
And then we want to group by name as a 2nd option so files with same modifcation is sorted by name:
sortBy=file:modifed;file:name
Now there is an issue here, can you spot it? Well the modified timestamp of the file is too fine as it will be in millis, but what if we want to sort by date only and then sub group by name? Well as we have the true power of File Language we can use the its date command that supports patterns. So this can be solved as:
sortBy=date:file:yyyyMMdd;file:name
Yeah that is pretty powerful, oh by the way you can also use reverse per group so we could reverse the file names:
sortBy=date:file:yyyyMMdd;reverse:file:name
This component has log level TRACE that can be helpful if you have problems.
File Language