Hi,
Is it possible to implement triggers or listeners or observers in hadoop
filesystem. Some change in hadoop filesystem notify to client application???--

Thanks,
sandeep

HBase has coprocessors which might help you with your use case.

https://blogs.apache.org/hbase/entry/coprocessor_introduction

Regards

Bertrand

On Thu, Jul 26, 2012 at 4:08 AM, Sandeep Reddy P <
[EMAIL PROTECTED]> wrote:

> Hi,
> Is it possible to implement triggers or listeners or observers in hadoop
> filesystem. Some change in hadoop filesystem notify to client
> application???--
>
> Thanks,
> sandeep
>

--
Bertrand Dechoux

Apache Oozie ( the workflow / coordination tool for Hadoop) has a feature
similar to this.

Take a look at
http://incubator.apache.org/oozie/docs/3.2.0-incubating/docs/CoordinatorFunctionalSpec.html-
there are triggers which allow you to perform actions when new data
appears on the filesystem in a specified location.

On 26 July 2012 03:08, Sandeep Reddy P <[EMAIL PROTECTED]> wrote:

> Hi,
> Is it possible to implement triggers or listeners or observers in hadoop
> filesystem. Some change in hadoop filesystem notify to client
> application???--
>
> Thanks,
> sandeep
>

Thanks for the info i'll give it a try and update you soon.

On Thu, Jul 26, 2012 at 4:21 AM, Dave Beech <[EMAIL PROTECTED]> wrote:

> Apache Oozie ( the workflow / coordination tool for Hadoop) has a feature
> similar to this.
>
> Take a look at
>
> http://incubator.apache.org/oozie/docs/3.2.0-incubating/docs/CoordinatorFunctionalSpec.html-
> there are triggers which allow you to perform actions when new data
> appears on the filesystem in a specified location.
>
> On 26 July 2012 03:08, Sandeep Reddy P <[EMAIL PROTECTED]>
> wrote:
>
> > Hi,
> > Is it possible to implement triggers or listeners or observers in hadoop
> > filesystem. Some change in hadoop filesystem notify to client
> > application???--
> >
> > Thanks,
> > sandeep
> >
>

--
Thanks,
sandeep

I have tried Apache Oozie 3.2.0 for hdfs trigger.

BUT oozie coordinator only support triggers combined time and data :

actually it scans hdfs periodcally , and check existence of "done-flag".

2012/7/26 Dave Beech <[EMAIL PROTECTED]>

> Apache Oozie ( the workflow / coordination tool for Hadoop) has a feature
> similar to this.
>
> Take a look at
>
> http://incubator.apache.org/oozie/docs/3.2.0-incubating/docs/CoordinatorFunctionalSpec.html-
> there are triggers which allow you to perform actions when new data
> appears on the filesystem in a specified location.
>
> On 26 July 2012 03:08, Sandeep Reddy P <[EMAIL PROTECTED]>
> wrote:
>
> > Hi,
> > Is it possible to implement triggers or listeners or observers in hadoop
> > filesystem. Some change in hadoop filesystem notify to client
> > application???--
> >
> > Thanks,
> > sandeep
> >
>