Webhooks

How to create a simple yet powerful webhooks mechanism in your PHP Application.

Transcript

1. WEBHOOKS PHPTour 2016
2. @guillaumepotier Cofounder & CTO Wisembly http://wisembly.com http://getsolid.io
3. Who never heard of webhooks? Should be a rhetorical question..
4. Who never used some?
5. Who already implemented webhooks in their application?
6. “A webhook in web development is a method of augmenting or altering the behavior of a web page, or web application, with custom callbacks. These callbacks may be maintained, modified, and managed by third-party users and developers who may not necessarily be affiliated with the originating website or application.” Wikipedia
7. “user defined callback made with HTTP POST” Jeff Lindsay
8. Push notifications / Reverse API
9. 1. consumer sets up a server to listen/consume callbacks 2. consumer registers callback URL with provider 3. provider makes requests to URL when a registered event happens
10. That’s all! Easy right?
13. A few examples
14. Google calendar PUSH notifications
15. Google calendar PUSH notifications
16. Github webhooks
17. Github webhooks
18. Digging deeper
19. ‣ a verb: POST ‣ an event: which could be subscribed by any user • for Github: pull_request, fork, commit, issues, etc.. ‣ a payload: containing the relevant data for the related event • often including: the resource itself, the sender (user who triggered the webhook) ‣ (optional) a security hash: to ensure webhook was delivered by the rightful authority • for Github: sharing a common secret used to generate a hash from the payload ‣ (optional) an ID webhook specs
20. ‣ a CRUD API • a payload URL: the server endpoint that will receive the webhook payload • events list: which events would you like to subscribe to • (optional) the content type ‣ (optional) an history of recent deliveries ‣ (mandatory) a good documentation :) • try to mirror API resources • document possible events • document security mechanisms its registration
23. Let’s implement it in your PHP application!* *We’ll see at least how we did it for Solid
25. https://getsolid.io
26. https://getsolid.io
27. https://getsolid.io
28. https://getsolid.io
29. 1. when a meeting is ended 2. when a task is created 3. when a task is assigned Solid implements these webhooks events
30. ‣ Various entities in your codebase could trigger webhooks ‣ Action that triggers webhooks could be in your services, your controllers, your commands. Pretty much everywhere ‣ You do not want to couple too much webhook logic from the rest of your application events to the rescue => use an event dispatcher symfony/event-dispatcher if you’re not using Symfony
31. events to the rescue ‣ We dispatch a single event listened by a WebhookSubscriber. In the DeliveryEvent we pass: • the event / action name • the related entity • the user that made the action triggering the webhook • (optional) changeset or other extra contextual params
32. ‣ lookup for registered users for each webhook could be consuming ‣ sending many POST requests for potential registered users *is* slow and consuming ‣ the API call that creates, updates or delete a resources and triggers the webhook does not need at all to be aware of all that stuff and worse, waiting for hooked URLs answers! RabbitMQ for the scalability => no need to do that stuff synchronously, use AMQP btw swarrot/swarrot is a great lib for RabbitMQ
33. RabbitMQ for the scalability
34. Command Entity Exporter (Sender) (Extra) Registred hooks HTTPs POST … HTTPs POST
35. The command ‣ pros • well decoupled from the rest of the codebase ‣ cons • some extra queries (need to re-fetch entities we had in previous context) • works only for stored entities retrievable with unique ID
36. The command
37. The exporter
38. The exporter
39. Testing / Tools
40. ngrok
41. requestb.in
42. symfony2 profiler
43. Zapier
44. Connect with 400+ apps
45. Still some work to do… https://github.com/Wisembly/Zapier
46. Still some work to do… https://github.com/Wisembly/Zapier
47. Bonus
48. Leverage webhooks for your company
49. Thank you Questions ? https://joind.in/talk/3c147