Two new CKAN extensions – Webhooks and Geopusher
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A problem I’ve had personally is having my open data apps know when a dataset they’ve been using has been updated. You can of course poll CKANperiodically, but then you need cron jobs or a queue, and when you’re using a cheap PaaS like heroku for your apps, integrating queues and cron is just an extra hassle.
This extension lets people register a URL with CKAN, which CKAN will call when a certain event happens – for example, a dataset update. The extension uses the built-in CKAN celery queue, so as to be non-blocking.
If you do end up using it, there are still a bunch of nice features to be built, including a simple web interface through which users can register webhooks (right now they can only be created through the action API)
So you know how you have a lot of Shapefiles and KML files in your CKANs (because government), but your users prefer GeoJSON? This extension will automatically convert shapefiles and KML into GeoJSON, and create a new GeoJSON resource within that dataset. There are some cases where this won’t work depending on complexity of SHP or KML file, but it works well in general.
This extension also uses the built-in celery queue to do its work, so for both of these extensions you will need to start the celery daemon in order to use them:
`paster –plugin=ckan celeryd -c development.ini`