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From Andy Wenk <andyw...@apache.org>
Subject Re: Post on Trigger
Date Thu, 19 May 2016 21:27:25 GMT
Matthew,

> On 19 May 2016, at 18:03, Matthew Rijk <mrijk11@gmail.com> wrote:
> 
> How can i unsubscribe to this feed

sorry to see you go. Please send an email to dev-unsubscribe@couchdb.apache.org with the email
address you are subscribed with.

All the best

Andy
--
Andy Wenk
Hamburg - Germany
RockIt!

GPG public key: https://pgp.mit.edu/pks/lookup?op=get&search=0x4F1D0C59BC90917D

> 
> On Thu, May 19, 2016 at 9:06 AM, Jan Lehnardt <jan@apache.org> wrote:
> 
>> Heya,
>> 
>> the easiest way to build this today is with a CouchDB External:
>> http://docs.couchdb.org/en/1.6.1/externals.html that listens to a
>> _changes feed.
>> 
>> You can use changes feed filters (
>> http://docs.couchdb.org/en/1.6.1/api/database/changes.html) to get the
>> “only when a doc is emitted” type of event you mention (or you filter that
>> in your external script). From the script then you can do whatever you want.
>> 
>> A CouchDB External is started and stopped (and kept alive) by CouchDB
>> itself, so you are saving yourself the effort of a system integration
>> startup script.
>> 
>> Best
>> Jan
>> --
>> 
>> 
>>> On 19 May 2016, at 13:49, Reddy B. <reddy.b@live.fr> wrote:
>>> 
>>> Hi,
>>> 
>>> I am fairly new to CouchDb and loving it so far. I think this database
>> is shockingly underated. I love the "Relax" approach and the design
>> choices  that have been done, and I hope things will continue with the same
>> philosophy.
>>> 
>>> I couldn't find if this has been discussed before but I was thinking
>> that it would be extremely cool to be able to setup triggers that POST
>> arbitrary json to arbitrary endpoints. I think this would be a killer
>> feature if there was built-in support for that - and seems to fit well with
>> the HTTP approach of couch.
>>> 
>>> So basically, this would be about allowing us to add an arbitrary number
>> of triggers to any view. Each trigger would be called only if the view
>> emitted "something" and the trigger would receive the document passed as a
>> parameter to the view (this is to take advantage of the update frequency of
>> views) Then in terms of posting, there could be a new built-in javascript
>> function calling curl behind the scenes which can be called from the
>> triggers.
>>> 
>>> For the same purpose, it would be interesting to introduce configuration
>> documents at the database level whose properties could be accessed from
>> these triggers (I'm thinking of situations when one would need to call a
>> different URL when in testing, staging, production etc...)
>>> 
>>> In terms of use case, this would allow us to do things as diverse as
>> sending email notifications, and maintenance tasks. More generally, this
>> would eliminate the need for most of the maintenance jobs out there while
>> making these systems much more efficient by removing the need to run jobs
>> at arbitrary times even when this is not necessary. Also, since most web
>> frameworks are asynchronous and process each request in a different
>> thread,  this would be a way to easily parallelize certain operations.
>>> 
>>> I just wanted to know if there was any chance to see this come out one
>> day or if this would be a "no-go" for design of philosophical reasons.
>>> 
>>> Cheers,
>>> 
>>> Reddy
>>> 
>> 
>> --
>> Professional Support for Apache CouchDB:
>> https://neighbourhood.ie/couchdb-support/
>> 
>> 


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