Hi

You can use a bit of Java code to read the file content into memory,
and then use xpath to extract that other file name.
Camel has some helper APIs for that in IOHelper#loadTexxt and XPathBuilder.

Here is some snippet from an unit test

@Test
public void testNotUsingExchangeResultType() throws Exception {
    String xml = "<xml><a>1</a><a>2</a></xml>";

    // will evaluate as NodeSet
    XPathBuilder xpb = new XPathBuilder("/xml/a/text()");
    assertEquals("12", xpb.evaluate(context, xml, String.class));

    xpb.setResultType(String.class);
    assertEquals("1", xpb.evaluate(context, xml));
}
On Thu, Dec 13, 2018 at 2:58 PM John F. Berry
<bohnje...@yahoo.com.invalid> wrote:
>
>  Thank you Claus.. it's great to hear from you again..
> I did see an example close to this on stackoverflow.. someone referenced a 
> bean as a filter to check for an extra file to exist, but in that example the 
> extra file's name that needed to exist was static.The "chicken or the egg" 
> question about that is.. I need to use the xpath in the current consumed XML 
> to determine what file should exist for the route to continue. I haven't seen 
> to many examples of parameter passing of the internal workings of a Camel 
> route to beans and the route accepting data from to use in <choice>.  I did 
> think I needed to pass this off to another java execution, thus the reason 
> I'm pulling my results to the log and so forth, but I still thought I needed 
> the facilites of the CamelContext to run first... or is the filter not really 
> so close on incept of an inbound file as I think?   Is the inbound "message" 
> (file in this case) really "consumed" as in loaded/headers made, etc. before 
> the filter instruction applies?
> Thanks for the heads up on noop.. I did know I had to address that once 
> things were in place.. I put it there to test "once throughs" and was going 
> to adjust that later in testing.
>
>
>     On ‎Thursday‎, ‎December‎ ‎13‎, ‎2018‎ ‎02‎:‎43‎:‎00‎ ‎AM‎ ‎EST, Claus 
> Ibsen <claus.ib...@gmail.com> wrote:
>
>  Hi
>
> Just use Java - You can use Java File API to check for the existence
> of a file ;)
>
> You can also use a file filter to only pickup the file where you check
> for the existence of that other file.
> You can then write a bit of Java code as the filter and configure it
> on the file endpoint. In the filter you grab the file context, do the
> xpath to extract the name, and check for the file exists.
>
> Also mind that noop=true will leave the file as-is after processing
> it, but will not pickup it again, unless you configure the idempotent
> to false also. Which you would need in cases while you may
> wait for that other file.
>
> So the better alternative is the file filter, and then move the files
> after it has been processed, so you wont process the file again in the
> future.
> On Thu, Dec 13, 2018 at 1:58 AM John F. Berry
> <bohnje...@yahoo.com.invalid> wrote:
> >
> > OK.. not hearing any pre-build advise.. I started building.
> > I can successfully extract the XML field value that is the name of the work 
> > file out of the consumed file of the route.
> > What I need to do is only move both (the file I'm consuming and it's work 
> > file).. if the work file shows up..
> >
> > Here's what I got so far....
> >
> >
> > package org.mainegeneral.camel;
> > import org.apache.camel.Processor;
> > import org.apache.camel.Exchange;
> > import org.apache.camel.builder.RouteBuilder;
> > public class MyRouteBuilder extends RouteBuilder {
> >    public void configure() {
> >        from("file:src/data?noop=true&include=.*\\.xml")
> >        
> > .setProperty("SourceFN").xpath("/SYSTEMJOB/WORKDETAIL/SOURCE_FILENAME", 
> > String.class)
> >        .process(new Processor() {
> >                      public void process(Exchange exchange) throws 
> > Exception {
> >              }
> >          } )
> >        .log("Reading XML file: ${header.CamelFileName}")
> >        .log("XML Source Filename = ${property.SourceFN}")
> >        .to("file:target/messages/others");
> >    }
> > }
> >
> >
> > Now I will need to not move the XML I'm consuming if the file named in 
> > SOURCE_FILENAME doesn't yet exist, and go on to the other XML files in the 
> > directory and come back to check this one.
> > I was going to use a choice to perform both those moves in.. but struggling 
> > to check for the named SOURCE_FILENAME's existance.
> >
> > Suggestions?
> >
> > Thanks!
> >
> >
> >
> >
> >
> > On Monday, December 10, 2018, 3:10:09 PM EST, John F. Berry 
> > <bohnje...@yahoo.com.INVALID> wrote:
> >
> >
> >
> >
> >
> > Figured I'd try something new and ask for advice here first before hitting 
> > a brick wall and asking after I hit that dead end...I need to poll for XML 
> > files dumping into a specific NFS directory, read in the XML, find the 
> > "work" file generated by the task that generated the XML, and move both 
> > files together.  The XML file is a custom small app specific job detail 
> > sort of file, with the exported work contained in a file named between the 
> > <SOURCE_FILENAME> tag.I could just regex the file, instead of parsing XML 
> > "officially", then use a choice and when satisfied, move both the file I'm 
> > reading, and the result from the regex.  I don't really need the 50 or so 
> > other job statistic tags contained in the XML.  I plan to use Java DSL with 
> > a blueprint or some Karaf supported type to run as a bundle.
> > Since these xml files are generated at invocation, the "work" file might 
> > not show up for a few minutes.  In that time, I'm hoping to round-robin any 
> > other XML files to find completed "pairs" in this landing directory. Sound 
> > simple enough?  Any gotchas that people can think of?
> > Thanks!
>
>
>
> --
> Claus Ibsen
> -----------------
> http://davsclaus.com @davsclaus
> Camel in Action 2: https://www.manning.com/ibsen2



-- 
Claus Ibsen
-----------------
http://davsclaus.com @davsclaus
Camel in Action 2: https://www.manning.com/ibsen2

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