Dhruv,
I agree there is effort involved in implementing webhooks. Your assessment mostly sound. Perhaps some details can be simplified. It comes down to 1) letting the user give you a callback URL, 2) deciding what events to trigger on and invoking that callback. You don't need to let users provide a different URL for each event. You don't need to define upfront what events you trigger on except for documentation.
Those two things alone should not be considerable effort for an average web developer. The hard parts are in the details. Hookah is an open source HTTP request queue and dispatcher made for deploying webhooks. You might look into that. I'm sprinting on it next week and refactoring the PSHB hub module out into a separate project.
Also, this might have been more appropriate on the webhooks mailing list? *shrug*
-jeff
--
Jeff Lindsay
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