Available in Fuse Mediation Router 2.3
The exec component can be used to execute a system command.
Maven users need to add the following dependency to their pom.xml
<dependency>
<groupId>org.apache.camel</groupId>
<artifactId>camel-exec</artifactId>
<version>${camel-version}</version>
</dependency>where ${camel-version} must be replaced by the actual version of Fuse Mediation Router
(2.3.0 or higher).
exec://executable[?options]
where executable is the name, or file path, of the system command that
will be executed. If executable name is used (e.g. exec:java), the
executable must in the system path.
| Name | Default value | Description |
|---|---|---|
args
|
null
|
The arguments of the executable. The arguments may be one or many
whitespace-separated tokens, that can be quoted with |
workingDir
|
null
|
The directory in which the command should be executed. If null, the
working directory of the current process will be used. |
timeout
|
Long.MAX_VALUE
|
The timeout, in milliseconds, after which the executable should be terminated. If the executable has has not finished within the timeout, the component will send a termination request. |
outFile
|
null
|
The name of a file, created by the executable, that should be considered as output of
the executable. If no outFile is set, the standard output (stdout) of
the executable will be considered as output. |
binding
|
a DefaultExecBinding instance |
A reference to a org.apache.commons.exec.ExecBinding in the Registry. |
commandExecutor
|
a DefaultCommandExecutor instance |
A reference to a org.apache.commons.exec.ExecCommandExecutor in the
Registry, that customizes
the command execution. The default command executor utilizes the commons-exec library. It adds a
shutdown hook for every executed command. |
useStderrOnEmptyStdout
|
false
|
A boolean which dictates when stdin is empty, it should fallback and
use stderr in the Message Body. This option is default
false. |
The supported headers are defined in
org.apache.camel.component.exec.ExecBinding.
| Name | Type | Message | Description |
|---|---|---|---|
ExecBinding.EXEC_COMMAND_EXECUTABLE
|
String
|
in
|
The name of the system command that will be executed. Overrides the
executable in the URI. |
ExecBinding.EXEC_COMMAND_ARGS
|
java.util.List<String>
|
in
|
The arguments of the executable. The arguments are used literally, no quoting is
applied. Overrides existing args in the URI. |
ExecBinding.EXEC_COMMAND_ARGS
|
String
|
in
|
Camel 2.5: The arguments of the executable as a Single string where each argument is whitespace separated (see args in URI option). The arguments are used literally, no quoting is applied. Overrides existing args in the URI. |
ExecBinding.EXEC_COMMAND_OUT_FILE
|
String
|
in
|
The name of a file, created by the executable, that should be considered as output of
the executable. Overrides existing outFile in the URI. |
ExecBinding.EXEC_COMMAND_TIMEOUT
|
long
|
in
|
The timeout, in milliseconds, after which the executable should be terminated. Overrides
existing timeout in the URI. |
ExecBinding.EXEC_COMMAND_WORKING_DIR
|
String
|
in
|
The directory in which the command should be executed. Overrides existing
workingDir in the URI. |
ExecBinding.EXEC_EXIT_VALUE
|
int
|
out
|
The value of this header is the exit value of the executable. Typically not-zero exit values indicates abnormal termination. Note that the exit value is OS-dependent. |
ExecBinding.EXEC_STDERR
|
java.io.InputStream
|
out
|
The value of this header points to the standard error stream (stderr) of the executable.
If no stderr is written, the value is null. |
ExecBinding.EXEC_USE_STDERR_ON_EMPTY_STDOUT
|
boolean
|
in
|
Indicates when the stdin is empty, should we fallback and use
stderr as the body of the Message. By default this option is
false. |
If the in message body, that that the Exec component
receives, is convertible to java.io.InputStream, it is used to feed input
of the executable via its stdin. After the execution, the message body is the result of the
execution, that is org.apache.camel.components.exec.ExecResult instance
containing the stdout, stderr, exit value and out file. The component supports the following
ExecResult
type converters for
convenience:
| From | To |
|---|---|
ExecResult
|
java.io.InputStream
|
ExecResult
|
String
|
ExecResult
|
byte []
|
ExecResult
|
org.w3c.dom.Document
|
If out file is used (the endpoint is configured with outFile, or there
is ExecBinding.EXEC_COMMAND_OUT_FILE header) the converters return the
content of the out file. If no out file is used, then the converters will use the stdout of
the process for conversion to the target type. For example refer to the usage examples.
The example below executes wc (word count, Linux) to count the words in
file /usr/share/dict/words. The word count (output) is written in the
standart output stream of wc.
from("direct:exec")
.to("exec:wc?args=--words /usr/share/dict/words")
.process(new Processor() {
public void process(Exchange exchange) throws Exception {
// By default, the body is ExecResult instance
assertIsInstanceOf(ExecResult.class, exchange.getIn().getBody());
// Use the Camel Exec String type converter to convert the ExecResult to String
// In this case, the stdout is considered as output
String wordCountOutput = exchange.getIn().getBody(String.class);
// do something with the word count
}
});The example below executes java with 2 arguments:
-server and -version, provided that
java is in the system path.
from("direct:exec")
.to("exec:java?args=-server -version")The example below executes java in c:/temp with 3
arguments: -server, -version and the sytem property
user.name.
from("direct:exec")
.to("exec:c:/program files/jdk/bin/java?args=-server -version -Duser.name=Camel&workingDir=c:/temp")The following example executes Apache Ant
(Windows only) with the build file CamelExecBuildFile.xml, provided that
ant.bat is in the system path, and that
CamelExecBuildFile.xml is in the current directory.
from("direct:exec")
.to(exec:ant.bat?args=-f CamelExecBuildFile.xml")In the next example, the ant.bat command, redirects the ant output to
CamelExecOutFile.txt with -l. The file
CamelExecOutFile.txt is used as out file with
outFile=CamelExecOutFile.txt. The example assumes that
ant.bat is in the system path, and that
CamelExecBuildFile.xml is in the current directory.
from("direct:exec")
.to("exec:ant.bat?args=-f CamelExecBuildFile.xml -l CamelExecOutFile.txt&outFile=CamelExecOutFile.txt")
.process(new Processor() {
public void process(Exchange exchange) throws Exception {
InputStream outFile = exchange.getIn().getBody(InputStream.class);
assertIsInstanceOf(InputStream.class, outFile);
// do something with the out file here
}
}); |  | |
 |
