How can Apache Camel be used to monitor file changes?

Question

I would like to monitor all of the files in a given directory for changes, ie an updated timestamp. This use case seems natural for Camel using the file component, but I can

Answer 1

I faced the same problem i.e. wanted to copy updated files also (along with new files). Below is my configuration,

public static void main(String[] a) throws Exception {

    CamelContext cc = new DefaultCamelContext();

    cc.addRoutes(createRouteBuilder());

    cc.start();

    Thread.sleep(10 * 60 * 1000);

    cc.stop();
}


protected static RouteBuilder createRouteBuilder() {
    return new RouteBuilder() {
        public void configure() {
            from("file://D:/Production"
                    + "?idempotent=true"
                    + "&idempotentKey=${file:name}-${file:size}"
                    + "&include=.*.log"
                    + "&noop=true"
                    + "&readLock=changed")

            .to("file://D:/LogRepository");
        }
    };
}

My testing steps:

1. Run the program and it copies few .log files from D:/Production to D:/LogRepository and then continues to poll D:/Production directory
2. I opened a already copied log say A.log from D:/Production (since noop=true nothing is moved) and edited it with some editor tool. This doubled the file size and save it.

At this point I think Camel is supposed to copy that particular file again since its size is modified and in my route definition I used "idempotent=true&idempotentKey=${file:name}-${file:size}&readLock=changed". But camel ignores the file. When I use TRACE for logging it says "Skipping as file is already in progress...", but I did not find any lock file in D:/Production directory when I editted and saved the file.

I also checked that camel still ignores the file if I replace A.log (with same name but bigger size) in D:/Production directory from outside.

But I found, everything is working as expected if I remove noop=true option.

Am I missing something?