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By the way, you cannot specify several tubes when you are writing jobs into Beanstalk.

Common URI options

Message headers

Producer UIR options

Producer behavior is affected by the command parameter which tells what to do with the job, it can beThe supported headers are defined in org.apache.camel.component.exec.ExecBinding.

Message body

Consumer UIR options

The consumer may delete the job immediately after reserving it or wait until Camel routes process it. While the first scenario is more like a “message queue”, the second is similar to “job queue”. This behavior is controlled by consumer.awaitJob parameter, which equals true by default (following Beanstalkd nature).

When synchronous, the consumer calls delete on successful job completion and calls bury on failure. You can choose which command to execute in the case of failure by specifying consumer.onFailure parameter in the URI. It can take values of bury, delete or release.

There is a boolean parameter consumer.useBlockIO which corresponds to the same parameter in JavaBeanstalkClient library. By default it is true.

Be careful when specifying release, as the failed job will immediately become available in the same tube and your consumer will try to acquire it again. You can release and specify jobDelay though.

 Consumer Headers

The consumer stores a number of job headers in the Exchange messageIf the Exec component receives an in message body that is convertible to java.io.InputStream, it is used to feed input to the executable via its stdin. After execution, the message body is the result of the execution,- that is, an org.apache.camel.components.exec.ExecResult instance containing the stdout, stderr, exit value, and out file. This component supports the following ExecResult type converters for convenience:

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Usage examples

Executing word count (Linux)

The example below executes wc (word count, Linux) to count the words in file /usr/share/dict/words. The word count (output) is written to the standard output stream of wc.

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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
     }
});

Executing java

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")

Executing Ant scripts

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 its output to CamelExecOutFile.txt with -l. The file CamelExecOutFile.txt is used as the 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.

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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
     }
  });

Executing echo (Windows)

Commands such as echo and dir can be executed only with the command interpreter of the operating system. This example shows how to execute such a command - echo - in Windows.

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from("direct:exec").to("exec:cmd?args=/C echo echoString")

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