Web app development - How to have inbound http requests hit multiple environments

Like most web development, I have multiple environments:

• Local development
• Cloud staging
• Cloud production
• Cloud-based web debugging services like RequestBin or Runscope which allow you to inspect http requests

etc.

During development and testing I would like to have inbound http requests (whether they are from users, 3rd party webhooks, etc.) hit multiple endpoints at the same time. Naturally I don't have control of the origination of those inbound requests.

How might I achieve for example, receiving a 3rd party webhook in both my production environment and development environment at the same time?