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Chapter 40. FTP2

FTP/SFTP Component

This component provides access to remote file systems over the FTP and SFTP protocols.
Consuming from remote FTP server
Make sure you read the section titled Default when consuming files further below for details related to consuming files.

URI format

ftp://[username@]hostname[:port]/directoryname[?options]
sftp://[username@]hostname[:port]/directoryname[?options]
ftps://[username@]hostname[:port]/directoryname[?options]
Where directoryname represents the underlying directory. Can contain nested folders.
If no username is provided, then anonymous login is attempted using no password. If no port number is provided, Apache Camel will provide default values according to the protocol (ftp = 21, sftp = 22, ftps = 21).
This component uses two different libraries for the actual FTP work. FTP and FTPS use Apache Commons Net while SFTP uses JCraft JSCH.
You can append query options to the URI in the following format, ?option=value&option=value&...

URI Options

The options below are exclusive to the FTP component:
Name Default Value Description
username null Specifies the username to use to log in to the remote file systen.
password null Specifies the password to use to log in to the remote file system.
binary false Specifies the file transfer mode, BINARY or ASCII. Default is ASCII (false).
disconnect false Camel 2.2: Whether or not to disconnect from remote FTP server right after use. Can be used for both consumer and producer. Disconnect will only disconnect the current connection to the FTP server. If you have a consumer which you want to stop, then you need to stop the consumer/route instead.
localWorkDirectory null When consuming, a local work directory can be used to store the remote file content directly in local files, to avoid loading the content into memory. This is beneficial, if you consume a very big remote file and thus can conserve memory. See below for more details.
passiveMode false FTP only: Specifies whether to use passive mode connections. Default is active mode {false).
securityProtocol TLS
FTPS only: Sets the underlying security protocol. The following values are defined: TLS: Transport Layer Security SSL: Secure Sockets Layer
disableSecureDataChannelDefaults false Camel 2.4: FTPS only: Whether or not to disable using default values for execPbsz and execProt when using secure data transfer. You can set this option to true if you want to be in absolute full control what the options execPbsz and execProt should be used.
download true Camel 2.11: Whether the FTP consumer should download the file. If this option is set to false, then the message body will be null, but the consumer will still trigger a Camel Exchange that has details about the file such as file name, file size, etc. It's just that the file will not be downloaded.
streamDownload false Camel 2.11: hether the consumer should download the entire file up front, the default behavior, or if it should pass an InputStream ead from the remote resource rather than an in-memory array as the in body of the amel Exchange.  his option is ignored if download s false r is localWorkDirectory is provided.  his option is useful for working with large remote files.
execProt null
Camel 2.4: FTPS only: Will by default use option P if secure data channel defaults hasn't been disabled. Possible values are: C: Clear S: Safe (SSL protocol only) E: Confidential (SSL protocol only) P: Private
execPbsz null Camel 2.4: FTPS only: This option specifies the buffer size of the secure data channel. If option useSecureDataChannel has been enabled and this option has not been explicit set, then value 0 is used.
isImplicit false FTPS only: Sets the security mode(implicit/explicit). Default is explicit (false).
knownHostsFile null SFTP only: Sets the known_hosts file, so that the SFTP endpoint can do host key verification.
knownHostsUri null SFTP only:Camel 2.11.1: Sets the known_hosts file (loaded from classpath by default), so that the SFTP endpoint can do host key verification.
keyPair null SFTP only:Camel 2.12.0: Sets the Java KeyPair for SSH public key authentication, it supports DSA or RSA keys.
privateKeyFile null SFTP only: Set the private key file to that the SFTP endpoint can do private key verification.
privateKeyUri null SFTP only:Camel 2.11.1: Set the private key file (loaded from classpath by default) to that the SFTP endpoint can do private key verification.
privateKey null SFTP only:Camel 2.11.1: Set the private key as byte[] to that the SFTP endpoint can do private key verification.
privateKeyFilePassphrase null SFTP only: Set the private key file passphrase to that the SFTP endpoint can do private key verification.
privateKeyPassphrase null SFTP only:Camel 2.11.1: Set the private key file passphrase to that the SFTP endpoint can do private key verification.
preferredAuthentications null SFTP only:Camel 2.10.7, 2.11.2,2.12.0: set the preferred authentications which SFTP endpoint will used. Some example include:password,publickey. If not specified the default list from JSCH will be used.
ciphers null Camel 2.8.2, 2.9: SFTP only Set a comma separated list of ciphers that will be used in order of preference. Possible cipher names are defined by JCraft JSCH. Some examples include: aes128-ctr,aes128-cbc,3des-ctr,3des-cbc,blowfish-cbc,aes192-cbc,aes256-cbc. If not specified the default list from JSCH will be used.
fastExistsCheck false Camel 2.8.2, 2.9: If set this option to be true, camel-ftp will use the list file directly to check if the file exists. Since some FTP server may not support to list the file directly, if the option is false, camel-ftp will use the old way to list the directory and check if the file exists. Note from Camel 2.10.1 onwards this option also influences readLock=changed to control whether it performs a fast check to update file information or not. This can be used to speed up the process if the FTP server has a lot of files.
strictHostKeyChecking no SFTP only:Camel 2.2: Sets whether to use strict host key checking. Possible values are: no, yes and ask. ask does not make sense to use as Camel cannot answer the question for you as its meant for human intervention. Note: The default in Camel 2.1 and below was ask.
maximumReconnectAttempts 3 Specifies the maximum reconnect attempts Apache Camel performs when it tries to connect to the remote FTP server. Use 0 to disable this behavior.
reconnectDelay 1000 Delay in millis Apache Camel will wait before performing a reconnect attempt.
connectTimeout 10000 Camel 2.4: Is the connect timeout in millis. This corresponds to using ftpClient.connectTimeout for the FTP/FTPS. For SFTP this option is also used when attempting to connect.
soTimeout null FTP and FTPS Only:Camel 2.4: Is the SocketOptions.SO_TIMEOUT value in millis. Note SFTP will automatic use the connectTimeout as the soTimeout.
timeout 30000 FTP and FTPS Only:Camel 2.4: Is the data timeout in millis. This corresponds to using ftpClient.dataTimeout for the FTP/FTPS. For SFTP there is no data timeout.
throwExceptionOnConnectFailed false Camel 2.5: Whether or not to thrown an exception if a successful connection and login could not be establish. This allows a custom pollStrategy to deal with the exception, for example to stop the consumer or the likes.
siteCommand null FTP and FTPS Only:Camel 2.5: To execute site commands after successful login. Multiple site commands can be separated using a new line character (\n). Use help site to see which site commands your FTP server supports.
stepwise true When consuming directories, specifies whether or not to use stepwise mode for traversing the directory tree. Stepwise means that it will CD one directory at a time. For more details, see the section called “Stepwise changing directories”.
separator Auto Camel 2.6: Dictates what path separator char to use when uploading files. Auto means use the path provided without altering it. UNIX means use UNIX style path separators. Windows means use Windows style path separators.
chmod null *SFTP Producer Only:* Camel 2.9: Allows you to set chmod on the stored file. For example chmod=640.
compression 0 *SFTP Only:* Camel 2.8.3/2.9: To use compression. Specify a level from 1 to 10. Important: You must manually add the needed JSCH zlib JAR to the classpath for compression support.
ftpClient null FTP and FTPS Only:Camel 2.1: Allows you to use a custom org.apache.commons.net.ftp.FTPClient instance.
ftpClientConfig null FTP and FTPS Only:Camel 2.1: Allows you to use a custom org.apache.commons.net.ftp.FTPClientConfig instance.
serverAliveInterval 0 SFTP Only:Camel 2.8 Allows you to set the serverAliveInterval of the sftp session
serverAliveCountMax 1 SFTP Only:Camel 2.8 Allows you to set the serverAliveCountMax of the sftp session
ftpClient.trustStore.file null FTPS Only: Sets the trust store file, so that the FTPS client can look up for trusted certificates.
ftpClient.trustStore.type JKS FTPS Only: Sets the trust store type.
ftpClient.trustStore.algorithm SunX509 FTPS Only: Sets the trust store algorithm.
ftpClient.trustStore.password null FTPS Only: Sets the trust store password.
ftpClient.keyStore.file null FTPS Only: Sets the key store file, so that the FTPS client can look up for the private certificate.
ftpClient.keyStore.type JKS FTPS Only: Sets the key store type.
ftpClient.keyStore.algorithm SunX509 FTPS Only: Sets the key store algorithm.
ftpClient.keyStore.password null FTPS Only: Sets the key store password.
ftpClient.keyStore.keyPassword null FTPS Only: Sets the private key password.
sslContextParameters null FTPS Only:Camel 2.9: Reference to a org.apache.camel.util.jsse.SSLContextParameters in the Registry. This reference overrides any configured SSL related options on ftpClient as well as the securityProtocol (SSL, TLS, etc.) set on FtpsConfiguration. See Using the JSSE Configuration Utility.
proxy null SFTP Only:Camel 2.10.7, 2.11.1: Reference to a com.jcraft.jsch.Proxy in the Registry. This proxy is used to consume/send messages from the target SFTP host.
useList true FTP/FTPS Only:Camel 2.12.1: Whether the consumer should use FTP LIST command to retrieve directory listing to see which files exists. If this option is set to false, then stepwise=false must be configured, and also fileName must be configured to a fixed name, so the consumer knows the name of the file to retrieve. When doing this only that single file can be retrieved. See further below for more details.
ignoreFileNotFoundOrPermissionError false Camel 2.12.1: Whether the consumer should ignore when a file was attempted to be retrieved but did not exist (for some reason), or failure due insufficient file permission error.
FTPS component default trust store
When using the ftpClient. properties related to SSL with the FTPS component, the trust store accept all certificates. If you only want trust selective certificates, you have to configure the trust store with the ftpClient.trustStore.xxx options or by configuring a custom ftpClient.
When using sslContextParameters, the trust store is managed by the configuration of the provided SSLContextParameters instance.
More options
See File for more options, as all the options from File are inherited by FTP2.
You can configure additional options on the ftpClient and ftpClientConfig from the URI directly by using the ftpClient. or ftpClientConfig. prefix.
For example to set the setDataTimeout on the FTPClient to 30 seconds you can do:
from("ftp://foo@myserver?password=secret&ftpClient.dataTimeout=30000")
    .to("bean:foo");
You can mix and match and have use both prefixes, for example to configure date format or timezones.
from("ftp://foo@myserver?password=secret&ftpClient.dataTimeout=30000&ftpClientConfig.serverLanguageCode=fr")
    .to("bean:foo");
You can have as many of these options as you like.
See the documentation of the Apache Commons FTP FTPClientConfig for possible options and more details. And as well for Apache Commons FTP FTPClient.
If you do not like having many and long configuration in the url you can refer to the ftpClient or ftpClientConfig to use by letting Camel lookup in the Registry for it.
For example:
   <bean id="myConfig" class="org.apache.commons.net.ftp.FTPClientConfig">
       <property name="lenientFutureDates" value="true"/>
       <property name="serverLanguageCode" value="fr"/>
   </bean>

And then let Camel lookup this bean when you use the # notation in the url.
from("ftp://foo@myserver?password=secret&ftpClientConfig=#myConfig").to("bean:foo");

More URI options

Important
See File2 as all the options there also applies for this component.

Examples

Here are some examples of FTP endpoint URIs:
ftp://someone@someftpserver.com/public/upload/images/holiday2008?password=secret&binary=true
ftp://someoneelse@someotherftpserver.co.uk:12049/reports/2008/password=secret&binary=false
ftp://publicftpserver.com/download
FTP Consumer does not support concurrency
The FTP consumer (with the same endpoint) does not support concurrency (the backing FTP client is not thread safe). You can use multiple FTP consumers to poll from different endpoints. It is only a single endpoint that does not support concurrent consumers.
The FTP producer does not have this issue, it supports concurrency.
More information
This component is an extension of the File2 component. So there are more samples and details on the File2 component page.

Default when consuming files

The FTP consumer will by default leave the consumed files untouched on the remote FTP server. You have to configure it explicit if you want it to delete the files or move them to another location. For example you can use delete=true to delete the files, or use move=.done to move the files into a hidden done sub directory.
The regular File consumer is different as it will by default move files to a .camel sub directory. The reason Camel does not do this by default for the FTP consumer is that it may lack permissions by default to be able to move or delete files.

limitations

The option readLock can be used to force Apache Camel not to consume files that are currently in the process of being written. However, this option is turned off by default, as it requires that the user has write access. There are other solutions to avoid consuming files that are currently being written over FTP; for instance, you can write to a temporary destination and move the file after it has been written.
The ftp producer does not support appending to existing files. Any existing files on the remote server will be deleted before the file is written.

Message Headers

The following message headers can be used to affect the behavior of the component
Header Description
CamelFileName Specifies the output file name (relative to the endpoint directory) to be used for the output message when sending to the endpoint. If this is not present and no expression either, then a generated message ID is used as the filename instead.
CamelFileNameProduced The actual absolute filepath (path + name) for the output file that was written. This header is set by Apache Camel and its purpose is providing end-users the name of the file that was written.
CamelFileBatchIndex Current index out of total number of files being consumed in this batch.
CamelFileBatchSize Total number of files being consumed in this batch.
CamelFileHost The remote hostname.
CamelFileLocalWorkPath Path to the local work file, if local work directory is used.
In addition the FTP/FTPS consumer and producer will enrich the Camel Message with the following headers:
Header Description
CamelFtpReplyCode Camel 2.11.1: The FTP client reply code (the type is a integer)
CamelFtpReplyString Camel 2.11.1: The FTP client reply string

About timeouts

The two sets of libraries (see above) have different APIs for setting the timeout. You can use the connectTimeout option for both of them to set a timeout in milliseconds to establish a network connection. An individual soTimeout can also be set on the FTP/FTPS, which corresponds to using ftpClient.soTimeout. Notice SFTP will automatically use connectTimeout as its soTimeout. The timeout option only applies for FTP/FTSP as the data timeout, which corresponds to the ftpClient.dataTimeout value. All timeout values are in milliseconds.

Using Local Work Directory

Apache Camel supports consuming from remote FTP servers and downloading the files directly into a local work directory. This avoids reading the entire remote file content into memory as it is streamed directly into the local file using FileOutputStream.
Apache Camel will store to a local file with the same name as the remote file, though with .inprogress as extension while the file is being downloaded. Afterwards, the file is renamed to remove the .inprogress suffix. And finally, when the Exchange is complete the local file is deleted.
So if you want to download files from a remote FTP server and store it as files then you need to route to a file endpoint such as:
from("ftp://someone@someserver.com?password=secret&localWorkDirectory=/tmp").to("file://inbox");
Optimization by renaming work file
The route above is ultra efficient as it avoids reading the entire file content into memory. It will download the remote file directly to a local file stream. The java.io.File handle is then used as the Exchange body. The file producer leverages this fact and can work directly on the work file java.io.File handle and perform a java.io.File.rename to the target filename. As Apache Camel knows it's a local work file, it can optimize and use a rename instead of a file copy, as the work file is meant to be deleted anyway.

Stepwise changing directories

Camel FTP can operate in two modes in terms of traversing directories when consuming files (for example, downloading) or producing files (for example, uploading):
  • stepwise
  • not stepwise
You may want to pick either one depending on your situation and security issues. Some Camel end users can only download files if they use stepwise, while others can only download if they do not. At least you have the choice to pick.
Note that stepwise changing of directory will in most cases only work when the user is confined to it's home directory and when the home directory is reported as /.
The difference between the two of them is best illustrated with an example. Suppose we have the following directory structure on the remote FTP server we need to traverse and download files:
      /
      /one
      /one/two
      /one/two/sub-a
      /one/two/sub-b
And that we have a file in each of sub-a (a.txt) and sub-b (b.txt) folder.

Using stepwise=true (default mode)

The following log shows the conversation between the FTP endpoint and the remote FTP server when the FTP endpoint is operating in stepwise mode:
      TYPE A
      200 Type set to A
      PWD
      257 "/" is current directory.
      CWD one
      250 CWD successful. "/one" is current directory.
      CWD two
      250 CWD successful. "/one/two" is current directory.
      SYST
      215 UNIX emulated by FileZilla
      PORT 127,0,0,1,17,94
      200 Port command successful
      LIST
      150 Opening data channel for directory list.
      226 Transfer OK
      CWD sub-a
      250 CWD successful. "/one/two/sub-a" is current directory.
      PORT 127,0,0,1,17,95
      200 Port command successful
      LIST
      150 Opening data channel for directory list.
      226 Transfer OK
      CDUP
      200 CDUP successful. "/one/two" is current directory.
      CWD sub-b
      250 CWD successful. "/one/two/sub-b" is current directory.
      PORT 127,0,0,1,17,96
      200 Port command successful
      LIST
      150 Opening data channel for directory list.
      226 Transfer OK
      CDUP
      200 CDUP successful. "/one/two" is current directory.
      CWD /
      250 CWD successful. "/" is current directory.
      PWD
      257 "/" is current directory.
      CWD one
      250 CWD successful. "/one" is current directory.
      CWD two
      250 CWD successful. "/one/two" is current directory.
      PORT 127,0,0,1,17,97
      200 Port command successful
      RETR foo.txt
      150 Opening data channel for file transfer.
      226 Transfer OK
      CWD /
      250 CWD successful. "/" is current directory.
      PWD
      257 "/" is current directory.
      CWD one
      250 CWD successful. "/one" is current directory.
      CWD two
      250 CWD successful. "/one/two" is current directory.
      CWD sub-a
      250 CWD successful. "/one/two/sub-a" is current directory.
      PORT 127,0,0,1,17,98
      200 Port command successful
      RETR a.txt
      150 Opening data channel for file transfer.
      226 Transfer OK
      CWD /
      250 CWD successful. "/" is current directory.
      PWD
      257 "/" is current directory.
      CWD one
      250 CWD successful. "/one" is current directory.
      CWD two
      250 CWD successful. "/one/two" is current directory.
      CWD sub-b
      250 CWD successful. "/one/two/sub-b" is current directory.
      PORT 127,0,0,1,17,99
      200 Port command successful
      RETR b.txt
      150 Opening data channel for file transfer.
      226 Transfer OK
      CWD /
      250 CWD successful. "/" is current directory.
      QUIT
      221 Goodbye
      disconnected.                                                 

As you can see when stepwise is enabled, it will traverse the directory structure using CD xxx.

Using stepwise=false

The following log shows the conversation between the FTP endpoint and the remote FTP server when the FTP endpoint is operating in non-stepwise mode:
      230 Logged on
      TYPE A
      200 Type set to A
      SYST
      215 UNIX emulated by FileZilla
      PORT 127,0,0,1,4,122
      200 Port command successful
      LIST one/two
      150 Opening data channel for directory list
      226 Transfer OK
      PORT 127,0,0,1,4,123
      200 Port command successful
      LIST one/two/sub-a
      150 Opening data channel for directory list
      226 Transfer OK
      PORT 127,0,0,1,4,124
      200 Port command successful
      LIST one/two/sub-b
      150 Opening data channel for directory list
      226 Transfer OK
      PORT 127,0,0,1,4,125
      200 Port command successful
      RETR one/two/foo.txt
      150 Opening data channel for file transfer.
      226 Transfer OK
      PORT 127,0,0,1,4,126
      200 Port command successful
      RETR one/two/sub-a/a.txt
      150 Opening data channel for file transfer.
      226 Transfer OK
      PORT 127,0,0,1,4,127
      200 Port command successful
      RETR one/two/sub-b/b.txt
      150 Opening data channel for file transfer.
      226 Transfer OK
      QUIT
      221 Goodbye
      disconnected.                              

As you can see when not using stepwise, there are no CD operation invoked at all.

Samples

In the sample below we set up Apache Camel to download all the reports from the FTP server once every hour (60 min) as BINARY content and store it as files on the local file system.
protected RouteBuilder createRouteBuilder() throws Exception {
    return new RouteBuilder() {
        public void configure() throws Exception {
            // we use a delay of 60 minutes (eg. once pr. hour we poll the FTP server
            long delay = 60 * 60 * 1000L;

            // from the given FTP server we poll (= download) all the files
            // from the public/reports folder as BINARY types and store this as files
            // in a local directory. Apache Camel will use the filenames from the FTPServer

            // notice that the FTPConsumer properties must be prefixed with "consumer." in the URL
            // the delay parameter is from the FileConsumer component so we should use consumer.delay as
            // the URI parameter name. The FTP Component is an extension of the File Component.
            from("ftp://tiger:scott@localhost/public/reports?binary=true&consumer.delay=" + delay).
                to("file://target/test-reports");
        }
    };
}
And the route using Spring DSL:
  <route>
     <from uri="ftp://scott@localhost/public/reports?password=tiger&inary=true&elay=60000"/>
     <to uri="file://target/test-reports"/>
  </route>

Consuming a remote FTP server triggered by a route

The FTP consumer is built as a scheduled consumer to be used in the from route. However, if you want to start consuming from an FTP server triggered within a route, use a route like the following:
from("seda:start")
   // define the file name so that only a single file is polled and deleted once retrieved
   .pollEnrich("ftp://admin@localhost:21/getme?password=admin&binary=false&fileName=myFile.txt&delete=true")
   .to("mock:result");

Consuming a remote FTPS server (implicit SSL) and client authentication

from("ftps://admin@localhost:2222/public/camel?password=admin&securityProtocol=SSL&isImplicit=true
      &ftpClient.keyStore.file=./src/test/resources/server.jks
      &ftpClient.keyStore.password=password&ftpClient.keyStore.keyPassword=password")
  .to("bean:foo");

Consuming a remote FTPS server (explicit TLS) and a custom trust store configuration

from("ftps://admin@localhost:2222/public/camel?password=admin&ftpClient.trustStore.file=./src/test/resources/server.jks&ftpClient.trustStore.password=password")
  .to("bean:foo");

Filter using org.apache.camel.component.file.GenericFileFilter

Apache Camel supports pluggable filtering strategies. You define a filter strategy by implementing the org.apache.camel.component.file.GenericFileFilter interface in Java. You can then configure the endpoint with the filter to skip certain files.
In the following sample we define a filter that only accepts files whose filename starts with report.
public class MyFileFilter<T> implements GenericFileFilter<T> {

    public boolean accept(GenericFile<T> file) {
        // we only want report files 
        return file.getFileName().startsWith("report");
    }
}
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.MyFileFilter"/>

  <route>
    <from uri="ftp://someuser@someftpserver.com?password=secret&filter=#myFilter"/>
    <to uri="bean:processInbox"/>
  </route>

Filtering using ANT path matcher

The ANT path matcher is a filter that 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 reason is that we leverage Spring's AntPathMatcher to do the actual matching.
The file paths are 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:
<bean class="org.springframework.beans.factory.config.PropertyPlaceholderConfigurer"/>
<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="myFTPEndpoint" uri="ftp://admin@localhost:${SpringFileAntPathMatcherRemoteFileFilterTest.ftpPort}/antpath?password=admin&ecursive=true&elay=10000&nitialDelay=2000&ilter=#myAntFilter"/>

    <route>
        <from ref="myFTPEndpoint"/>
        <to uri="mock:result"/>
    </route>
</camelContext>

<!-- we use the AntPathMatcherRemoteFileFilter to use ant paths for includes and exclude -->
<bean id="myAntFilter" class="org.apache.camel.component.file.AntPathMatcherGenericFileFilter">
    <!-- include any files in the sub-folder that have 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>

Using a proxy with SFTP

To use an HTTP proxy to connect to your remote host, you can configure your route in the following way:
<!-- define our sorter as a plain spring bean -->
<bean id="proxy" class="com.jcraft.jsch.ProxyHTTP">
  <constructor-arg value="localhost"/>
  <constructor-arg value="7777"/>
</bean>

<route>
  <from uri="sftp://localhost:9999/root?username=admin&password=admin&proxy=#proxy"/>
  <to uri="bean:processFile"/>
</route>
You can also assign a user name and password to the proxy, if necessary. Please consult the documentation for com.jcraft.jsch.Proxy to discover all options.

Consuming a single file using a fixed name

When you want to download a single file and knows the file name, you can use fileName=myFileName.txt to tell Camel the name of the file to download. By default the consumer will still do a FTP LIST command to do a directory listing and then filter these files based on the fileName option. Though in this use-case it may be desirable to turn off the directory listing by setting useList=false. For example the user account used to login to the FTP server may not have permission to do a FTP LIST command. So you can turn off this with useList=false, and then provide the fixed name of the file to download with fileName=myFileName.txt, then the FTP consumer can still download the file. If the file for some reason does not exist, then Camel will by default throw an exception, you can turn this off and ignore this by setting ignoreFileNotFoundOrPermissionError=true.
For example to have a Camel route that pickup a single file, and delete it after use you can do
from("ftp://admin@localhost:21/nolist/?password=admin&stepwise=false&useList=false&ignoreFileNotFoundOrPermissionError=true&fileName=report.txt&delete=true")
  .to("activemq:queue:report");
Notice that we have use all the options we talked above above.
You can also use this with ConsumerTemplate. For example to download a single file (if it exists) and grab the file content as a String type:
String data = template.retrieveBodyNoWait("ftp://admin@localhost:21/nolist/?password=admin&stepwise=false&useList=false&ignoreFileNotFoundOrPermissionError=true&fileName=report.txt&delete=true", String.class);

Debug logging

This component has log level TRACE that can be helpful if you have problems.