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 to be saved to disk.
file:directoryName[?options]
or
file://directoryName[?options]
Where directoryName represents the underlying file directory.
You can append query options to the URI in the following format,
?option=value&option=value&...
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, e.g.
by 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. |
Avoid reading files currently being written by another application | |
---|---|
Beware the JDK File IO API is a bit limited in detecting whether another application is
currently writing/copying a file. And the implementation can be different depending on OS
platform as well. This could lead to that Fuse Mediation Router thinks the file is not locked by another
process and start consuming it. Therefore you have to do you own investigation as to what
suits your environment. To help with this, Fuse Mediation Router provides different
|
Name | Default Value | Description |
---|---|---|
autoCreate
|
true
|
Automatically create missing directories in the file's pathname. For the file consumer, that means creating the starting directory. For the file producer, it means the directory where the files should be written. |
bufferSize
|
128kb | Write buffer sized in bytes. |
fileName
|
null
|
Use Expression such as File Language to dynamically set the filename. For consumers, it's used as a
filename filter. For producers, it's used to evaluate the filename to write. If an
expression is set, it take precedence over the CamelFileName header.
(Note: The header itself can also be an Expression). The expression options support both
String and Expression types. If the expression is
a String type, it is always evaluated
using the File Language. If the expression is an
Expression type, the specified Expression type is
used - this allows you, for instance, to use OGNL expressions.
For the consumer, you can use it to filter filenames, so you can for instance consume
today's file using the File Language syntax:
mydata-${date:now:yyyyMMdd}.txt . |
flatten
|
false
|
Flatten is used to flatten the file name path to strip any leading paths, so it's just
the file name. This allows you to consume recursively 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.
|
charset
|
null
|
Camel 2.5: this option is used to specify the encoding of the file, and camel will set the Exchange property with Exchange.CHARSET_NAME with the value of this option. |
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
|
true
|
Set to true to use fixed delay between pools, otherwise fixed rate
is used. See ScheduledExecutorService in JDK for details. |
runLoggingLevel
|
TRACE
|
Camel 2.8: The consumer logs a start/complete log line when it polls. This option allows you to configure the logging level for that. |
recursive
|
false
|
If a directory, will look for files in all the sub-directories as well. |
delete
|
false
|
If true , the file will be deleted after it is processed |
noop
|
false
|
If true , the file is not moved or deleted in any way. This option is
good for readonly data, or for ETL type requirements. If
noop=true , Fuse Mediation Router will set idempotent=true as
well, to avoid 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 files 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 . |
moveFailed
|
null
|
Use Expression such as File Language to dynamically set the filename when moving failed files after processing. To move files into a error
subdirectory just enter error . Note:
When moving the files to another location it can/will handle the error when you move it to another location so Fuse Mediation Router cannot
pick up the file again. |
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 Fuse Mediation Router skip already processed files. Will by 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 by default
use MemoryMessageIdRepository if none is specified and
idempotent is true . |
inProgressRepository
|
memory
|
Pluggable in-progress repository as a org.apache.camel.processor.idempotent.MessageIdRepository class. The in-progress repository is used to account the current in progress files being consumed. By default a memory based repository is used. |
filter
|
null
|
Pluggable filter as a
org.apache.camel.component.file.GenericFileFilter class. Will skip
files if filter returns false in its accept()
method. Fuse Mediation Router 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<org.apache.camel.component.file.GenericFile> class. |
sortBy
|
null
|
Built-in sort 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 on the file (i.e. the file is not in-progress or being written). Fuse Mediation Router will wait until the file lock is granted. The
|
readLockTimeout
|
0 (for FTP, 2000 ) |
Optional timeout in milliseconds 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. Currently fileLock , changed and
rename support the timeout. |
readLockCheckInterval
|
1000 (for FTP, 5000 ) |
Camel 2.6: Interval in millis for the read-lock, if
supported by the read lock. This interval is used for sleeping between attempts to acquire
the read lock. For example when using the changed read lock, you can
set a higher interval period to cater for slow writes. The default of
1 sec. may be too fast if the producer is very slow writing the file.
|
exclusiveReadLockStrategy
|
null
|
Pluggable read-lock as a
org.apache.camel.component.file.GenericFileExclusiveReadLockStrategy
implementation. |
minDepth
|
0 | Camel 2.8: The minimum depth to start processing when recursively processing a directory. Using minDepth=1 means the base directory. Using minDepth=2 means the first sub directory. This option is not supported by FTP consumer. |
maxDepth
|
Integer.MAX_VALUE
|
Camel 2.8: The maximum depth to traverse when recursively processing a directory. This option is not supported by FTP consumer. |
doneFileName
|
null
|
Camel 2.6: If provided, Camel will only consume files if a done file exists. This option configures what file name to use. Either you can specify a fixed name. Or you can use dynamic placeholders. The done file is always expected in the same folder as the original file. See using done file and writing done file sections for examples. |
processStrategy
|
null
|
A pluggable
org.apache.camel.component.file.GenericFileProcessStrategy allowing
you to implement your own readLock option or similar. Can also be used
when special conditions must be met before a file can be consumed, such as a special
ready file exists. If this option is set then the
readLock option does not apply. |
maxMessagesPerPoll
|
0
|
An integer that defines the maximum number of messages to gather per poll. By default, no maximum is set. Can be used to set a limit of e.g. 1000 to avoid having the server read thousands of files as it starts up. Set a value of 0 or negative to disabled it. |
startingDirectoryMustExist
|
false
|
Whether the starting directory must exist. Mind that the autoCreate option
is default enabled, which means the starting directory is normally auto-created if it
doesn't exist. You can disable autoCreate and enable this to ensure the
starting directory must exist. Will throw an exception, if the directory doesn't exist.
|
directoryMustExist
|
false
|
Similar to startingDirectoryMustExist but this applies during polling
recursive sub-directories. |
By default the file is locked for the duration of the processing.
After the route has completed, files are moved into the
.camel
subdirectory, so that they appear to be deleted.The File Consumer will always skip any file whose name starts with a dot, such as
.
,.camel
,.m2
or.groovy
.Only files (not directories) are matched for valid filename, if options such as:
includeNamePrefix
,includeNamePostfix
,excludeNamePrefix
,excludeNamePostfix
,regexPattern
are used.
Name | Default Value | Description |
---|---|---|
fileExist
|
Override
|
What to do if a file already exists with the same name. The following values can be
specified: Override, Append, Fail and Ignore. Override , which is the default, replaces the
existing file. Append adds content to the existing file.
Fail throws a GenericFileOperationException ,
indicating that there is already an existing file. Ignore silently
ignores the problem and does not override the existing
file, but assumes everything is okay. |
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. |
tempFileName
|
null
|
Camel 2.1: The same as
tempPrefix option but offering a more fine grained control on the
naming of the temporary filename as it uses the File
Language. |
keepLastModified
|
false
|
Camel 2.2: Will keep the last modified timestamp from
the source file (if any). Will use the Exchange.FILE_LAST_MODIFIED
header to located the timestamp. This header can contain either a
java.util.Date or long with the timestamp. If the
timestamp exists and the option is enabled it will set this timestamp on the written file.
Note: This option only applies to the file producer. You cannot use this option
with any of the ftp producers. |
eagerDeleteTargetFile
|
true
|
Camel 2.3: Whether or not to eagerly delete any
existing target file. This option only applies when you use
fileExists=Override and the tempFileName option as
well. You can use this to disable (set it to false) deleting the target file before the
temp file is written. For example you may write big files and want the target file to
exists during the temp file is being written. This ensure the target file is only deleted
until the very last moment, just before the temp file is being renamed to the target
filename. |
doneFileName
|
null
|
Camel 2.6: If provided, then Camel will write a 2nd done file when the original file has been written. The done file will be empty. This option configures what file name to use. Either you can specify a fixed name. Or you can use dynamic placeholders. The done file will always be written in the same folder as the original file. See writing done file section for examples. |
By default it will override any existing file, if one exist with the same name. In Fuse Mediation Router 1.x the
Append
is the default for the file producer. We have changed this toOverride
in Fuse Mediation Router 2.0 as this is also the default file operation usingjava.io.File
. And also the default for the FTP library we use in the camel-ftp component.
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://inbox?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
object. 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 options should be a directory name, which 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 .camel
sub-folder
relative to the directory where the file was consumed.
If you want to delete the file after processing, 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 have been scanned as they are moved to this sub folder before being processed.
from("file://inbox?preMove=inprogress").to("bean:handleOrder");
You can combine the pre move and the regular move:
from("file://inbox?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
an expression containing ${ }
, the expression is interpreted as a File Language
expression.
So if we want to move the file into a backup folder with today's date as the pattern, we can do:
move=backup/${date:now:yyyyMMdd}/${file:name}
The moveFailed
option allows you to move files that could not be processed succesfully to another location such as a
error folder of your choice. For example to move the files in an error folder with a timestamp
you can use
moveFailed=/error/${file:name.noext}-${date:now:yyyyMMddHHmmssSSS}.${file:name.ext}
.
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 it's
null then Fuse Mediation Router will auto-generate a filename based on the message
unique ID. |
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 with the name of the file that was written. |
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 (the name with no leading paths). |
CamelFileAbsolute
|
A boolean option specifying whether the consumed file denotes an
absolute path or not. Should normally be false for relative paths.
Absolute paths 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 value containing the file size. |
CamelFileLastModified
|
A Date value containing the last modified timestamp of the file.
|
This component implements the Batch Consumer.
As the file consumer is BatchConsumer
it supports batching the files it
polls. By batching it means that Fuse Mediation Router will add some properties to the Exchange so you know the number of files polled the current index
in that order.
Property | Description |
---|---|
CamelBatchSize
|
The total number of files that was polled in this batch. |
CamelBatchIndex
|
The current index of the batch. Starts from 0. |
CamelBatchComplete
|
A boolean value indicating the last Exchange in the batch. Is only true for the last entry. |
This allows you for instance to know how many files exists in this batch and for instance let the Aggregator2 aggregate this number of files.
When Fuse Mediation Router is producing files (writing files) there are a few gotchas affecting 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 you must provide a filename in the CamelFileName
message
header. 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");
Or 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.
Beware if you consume files from a folder where other applications write files directly.
Take a look at the different readLock
options to see what suits your use
cases. The best approach is however to write to another folder and after the write move the
file in the drop folder. However if you write files directly to the drop folder then the
option changed
could better detect whether a file is currently being
written/copied as it uses a file changed algorithm to see whether the file size / modification
changes over a period of time. The other read lock options rely on Java File API that sadly is
not always very good at detecting this. You may also want to look at the
doneFileName
option, which uses a marker file (done) to signal when a
file is done and ready to be consumed.
Available as of Camel 2.6
See also section writing done files below.
If you want only to consume files when a done file exists, then you can use the
doneFileName
option on the endpoint.
from("file:bar?doneFileName=done");
Will only consume files from the bar folder, if a file name done exists in the same directory as the target files. Camel will automatically delete the done file when it's done consuming the files.
However its more common to have one done file per target file. This means there is a 1:1
correlation. To do this you must use dynamic placeholders in the
doneFileName
option. Currently Camel supports the following two dynamic
tokens: file:name
and file:name.noext
which must be
enclosed in ${ }. The consumer only supports the static part of the done file name as either
prefix or suffix (not both).
from("file:bar?doneFileName=${file:name}.done");
In this example only files will be polled if there exists a done file with the name file name.done. For example
hello.txt
- is the file to be consumedhello.txt.done
- is the associated done file
You can also use a prefix for the done file, such as:
from("file:bar?doneFileName=ready-${file:name}");
hello.txt
- is the file to be consumedready-hello.txt
- is the associated done file
Available as of Camel 2.6
After you have written af file you may want to write an additional
done file as a kinda of marker, to indicate to others that the file is
finished and has been written. To do that you can use the doneFileName
option on the file producer endpoint.
.to("file:bar?doneFileName=done");
Will simply create a file named done
in the same directory as the
target file.
However its more common to have one done file per target file. This means there is a 1:1
correlation. To do this you must use dynamic placeholders in the
doneFileName
option. Currently Camel supports the following two dynamic
tokens: file:name
and file:name.noext
which must be
enclosed in ${ }
.
.to("file:bar?doneFileName=done-${file:name}");
Will for example create a file named done-foo.txt
if the target file
was foo.txt
in the same directory as the target file.
.to("file:bar?doneFileName=${file:name}.done");
Will for example create a file named foo.txt.done
if the target file
was foo.txt
in the same directory as the target file.
.to("file:bar?doneFileName=${file:name.noext}.done");
Will for example create a file named foo.done
if the target file was
foo.txt
in the same directory as the target file.
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 recursively into sub-directories. Will lay out the files in the same directory
structure in the outputdir
as the inputdir
, including
any sub-directories.
inputdir/foo.txt inputdir/sub/bar.txt
Will result in the following output layout:
outputdir/foo.txt outputdir/sub/bar.txt
If you want to store the files in the outputdir directory in the same directory,
disregarding the source directory layout (e.g. to flatten out the path), you just add the
flatten=true
option on the file producer side:
from("file://inputdir/?recursive=true&delete=true").to("file://outputdir?flatten=true")
Will result in the following output layout:
outputdir/foo.txt outputdir/bar.txt
Fuse Mediation Router will by default move any processed file into a .camel
subdirectory in the directory the file was consumed from.
from("file://inputdir/?recursive=true&delete=true").to("file://outputdir")
Affects the layout as follows: 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 } });
The body will be a File
object that points to the file that was just
dropped into 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
object as the 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, which is probably what you want.
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, i.e. produce files. In the sample below we receive some reports on the SEDA queue that we process 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("direct: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("direct:reports").processRef("processReport").to("file://target/test-reports", "mock:result"); } }; } private static 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 today's date as a sub-folder name:
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 an in-memory based store for keeping track of consumed files, it
uses a least recently used cache 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 the specified id
.
<!-- define our store as a plain spring bean --> <bean id="myStore" class="com.mycompany.MyIdempotentStore"/> <route> <from uri="file://inbox?idempotent=true&dempotentRepository=#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
stores the key in separate lines in the file. By default, the file store has a size limit of
1mb and when the file grows larger, Fuse Mediation Router will truncate the file store and rebuild the
content by flushing the 1st level cache into 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. Fuse Mediation Router 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 xmlns="http://camel.apache.org/schema/spring"> <route> <from uri="file://target/fileidempotent/?idempotent=true&dempotentRepository=#fileStore&ove=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 then we just need to reference the jpaStore bean in
the file consumer endpoint, using the idempotentRepository
option and the
#
syntax:
<route> <from uri="file://inbox?idempotent=true&dempotentRepository=#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 built 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 defined
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&ilter=#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 built 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().compareToIgnoreCase(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>
Fuse Mediation Router supports pluggable sorting strategies. This strategy it to use the File Language to configure the sorting. The
sortBy
option is configured as follows:
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:length
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 milliseconds, but what if we want to sort by date only and then subgroup 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
The option processStrategy
can be used to use a custom
GenericFileProcessStrategy
that allows you to implement your own
begin, commit and rollback
logic. For instance lets assume a system writes a file in a folder you should consume. But you
should not start consuming the file before another ready file have been
written as well.
So by implementing our own GenericFileProcessStrategy
we can implement
this as:
In the
begin()
method we can test whether the special ready file exists. The begin method returns aboolean
to indicate if we can consume the file or not.in the
commit()
method we can move the actual file and also delete the ready file.
This component has log level TRACE that can be helpful if you have problems.
See also: