FTP/SFTP Component
This component provides access to remote file systems over the FTP and SFTP protocols.
This component is an extension of the [File] component.
URI format
ftp://[username@]hostname[:port]/filename[?options] sftp://[username@]hostname[:port]/filename[?options]
Where filename represents the underlying file name or directory. Can contain nested folders.
The username is currently only possible to provide in the hostname parameter.
If no username is provided then anonymous
login is attempted using no password.
If no port number is provided. Camel will provide default values according to the protocol. (ftp = 21, sftp = 22)
Examples
ftp://someone@someftpserver.com/public/upload/images/holiday2008?password=secret&binary=true
ftp://someoneelse@someotherftpserver.co.uk:12049/reports/2008/budget.txt?password=secret&binary=false&directory=false
ftp://publicftpserver.com/download
Timestamp
In Camel 1.4 or older the FTP consumer uses an internal timestamp for last polling. This timestamp is used to match for new remote files: if remote file modified timestamp > last poll timestamp => file can be consumed.
In Camel 1.5 this algorithm has been disabled by default as its not reliable over the FTP protocol. FTP Servers only return file modified timestamps using HH:mm (not seconds). And of course the clocks between the client and server can also be out of sync. Bottom line is that timestamp check for FTP protocol should not be used. That is why this feature is marked as @deprecated and will be removed in Camel 2.0.
We encourage you to use a different strategy for matching new remote files: such as deleting or moving the file after download.
Options
Name |
Default Value |
Description |
---|---|---|
directory |
true |
indicates whether or not the given file name should be interpreted by default as a directory or file (as it sometimes hard to be sure with some FTP servers) |
password |
null |
specifies the password to use to login to the remote file system |
binary |
false |
specifies the file transfer mode BINARY or ASCII. Default is ASCII. |
ftpClientConfig |
null |
Camel 1.5: Reference to a bean in the registry as a |
consumer.recursive |
true/false |
if a directory, will look for changes in files in all the sub directories. Is true as default for Camel 1.4 or older. Will change to false as default value as of Camel 1.5 |
consumer.setNames |
true |
Used by FTPConsumer. If true Camel will use the filename the file has on the FTP server. The filename is stored on the IN message in the header |
consumer.delay |
500 |
Delay in millis between each poll |
consumer.initialDelay |
1000 |
Millis before polling starts |
consumer.userFixedDelay |
false |
true to use fixed delay between pools, otherwise fixed rate is used. See ScheduledExecutorService |
consumer.regexPattern |
null |
Used by FTPConsumer. Regular expression to use for matching files when consuming. |
consumer.exclusiveReadLock |
false |
Camel 1.5: Used by FTPConsumer. If set to true Camel will only poll the ftp files if it has exclusive read to the file (= the file is not in progress of being written). Camel will wait until it is granted, testing once every second. The test is implemented by Camel will try to rename the file. Setting to false Camel will poll the file even if its in progress of being written. |
consumer.deleteFile |
false |
Camel 1.5: Used by FTPConsumer. Flag to set if the consumed file should be deleted after it has been downloaded. |
consumer.moveNamePrefix |
null |
Camel 1.5: Used by FTPConsumer. The prefix String perpended to the filename when moving it. For example to move processed files into the done directory, set this value to 'done/' |
consumer.moveNamePostfix |
null |
Camel 1.5: Used by FTPConsumer. The postfix String appended to the filename when moving it. For example to rename processed files from foo to foo.old set this value to '.old' |
consumer.excludedNamePrefix |
null |
Camel 1.5: Used by FTPConsumer. Is used to exclude files if filename is starting with the given prefix. |
consumer.excludedNamePostfix |
null |
Camel 1.5: Used by FTPConsumer. Is used to exclude files if filename is ending with the given postfix. |
consumer.timestamp |
false |
Camel 1.5: @deprecated will be removed in Camel 2.0. This option is only for backwards comparability. |
expression |
null |
Camel 1.5: Use expression to dynamically set the filename. This allows you to very easily set dynamic pattern style filenames. If an expression is set it take precedes over the |
passiveMode |
false |
Camel 1.5.1/2.0: Set whether to use passive mode connections. Default is active. This feature is only for regular FTP, not SFTP. |
knownHosts |
null |
Camel 1.5.1/2.0: Sets the known_hosts file so that the SFTP endpoint can do host key verification. |
privateKeyFile |
null |
Camel 1.5.1/2.0: Set the private key file to that the SFTP endpoint can do private key verification. |
privateKeyFilePassphrase |
null |
Camel 1.5.1/2.0: Set the private key file passphrase to that the SFTP endpoint can do private key verification. |
tempPrefix |
null |
Camel 2.0: Option for ftp/sftp producer only. This option is used to upload the file using a temporary name, and then after the upload is complete rename it to the real name. Can be used to identify files being uploaded and also avoid consumers (not using exclusive read locks) reading in progress files. |
New default behavior for FTP/SFTP-Consumers in Camel 1.5
The 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: consumer.regexPattern, consumer.excludeNamePrefix, consumer.excludeNamePostfix
is used.
The consumer recursive option will be changed from true to false as the default value. We don't feel that Camel out-of-the-box should recursive poll.
The consumer will not use timestamp algorithm for determine if a remote file is a new file - see warning section above. To use the old behavior of Camel 1.4 or older you can use the option consumer.timestamp=true
.
Exclusive Read Lock
The new option consumer.exclusiveReadLock can be used to force Camel not to consume files that is currently in the progress of being written. However this option is default turned off, 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 the a temporary destination and move the file after it has been written.
Message Headers
The following message headers can be used to affect the behavior of the component
Header |
Description |
---|---|
org.apache.camel.file.name |
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 filename instead. |
org.apache.camel.file.name.produced |
New in Camel 1.5: 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. |
file.remote.host |
The hostname of the remote server |
file.remote.name |
The name of the file consumed from the remote server |
file.remote.fullName |
The fullname of the file consumed from the remote server |
Consumer properties
When using FTPConsumer (downloading files from a FTP Server) the consumer specific properties from the [File] component should be prefixed with "consumer.". For example the delay option from File Component should be specified as "consumer.delay=30000" in the URI. See the samples or some of the unit tests of this component.
Filename Expression
In Camel 1.5 we have support for setting the filename using an expression. This can be set either using the expression option or as a string based File Language expression in the org.apache.camel.file.name
header. See the File Language for some samples.
Known issues
See the timestamp warning.
When consuming files (downloading) you must use type conversation to either String or to InputStream for ASCII and BINARY file types.
In Camel 1.4 this is fixed, as there are build in type converters for the ASCII and BINARY file types, meaning that you do not need the convertBodyTo expression.
In Camel 1.4 or below Camel FTPConsumer will poll files regardless if the file is currently being written. See the consumer.exclusiveReadLock option.
Also in Camel 1.3 since setNames is default false then you must explicitly set the filename using the setHeader expression when consuming from FTP directly to File.
The code below illustrates this:
private String ftpUrl = "ftp://camelrider@localhost:21/public/downloads?password=admin&binary=false"; private String fileUrl = "file:myfolder/?append=false&noop=true"; return new RouteBuilder() { public void configure() throws Exception { from(ftpUrl).setHeader(FileComponent.HEADER_FILE_NAME, constant("downloaded.txt")).convertBodyTo(String.class).to(fileUrl); } };
Or you can set the option to true as illustrated below:
private String ftpUrl = "ftp://camelrider@localhost:21/public/downloads?password=admin&binary=false&consumer.setNames=true"; private String fileUrl = "file:myfolder/?append=false&noop=true"; return new RouteBuilder() { public void configure() throws Exception { from(ftpUrl).convertBodyTo(String.class).to(fileUrl); } };
Sample
In the sample below we setup 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.
And the route using Spring DSL:
<route> <from uri="ftp://scott@localhost/public/reports?password=tiger&binary=true&consumer.delay=60000"/> <to uri="file://target/test-reports"/> </route>
Using expression for filenames
In this sample we want to move consumed files to a backup folder using today's date as a sub foldername. Notice that the move happens on the remote FTP server. If you want to store the downloaded file on your local disk then route it to the [File] component as the sample above illustrates.
from(ftpUrl + "&expression=backup/${date:now:yyyyMMdd}/${file:name}").to("...");
See File Language for more samples.
Consuming a remote FTP server triggered by a route
The FTP consumer is build as a scheduled consumer to be used in the from route. However if you want to start consuming from a FTP server triggered within a route it's a bit cumbersome to do this in Camel 1.x (we plan to improve this in Camel 2.x). However it's possible as this code below demonstrates.
In the sample we have a SEDA queue where a message arrives that holds a message containing a filename to poll from a remote FTP server. So we setup a basic FTP url as:
And then we have the route where we use Processor within the route so we can use Java code. In this Java code we create the ftp consumer that downloads the file we want. And after the download we can get the content of the file and put it in the original exchange that continues being routed. As this is based on an unit test it routes to a Mock endpoint.
Debug logging
This component has log level TRACE that can be helpful if you have problems.