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how everything is connected (for now)

There are currently three different parts:

  • A "requester" client that will request for a door opening.
  • A single "target" client (the Raspberry Pi) that will receive requests
  • A central server that will relay the messages between the "requester" clients and "target" client

The messaging is done using WebSocket--really great stuff.

"Requester" Client
Currently just a simple PHP/JavaScript page that can send a textual message to the central server.

"Target" Client
A Python script that keeps an active WebSocket connection to the central server. As said above, this is executed in the Raspberry Pi.

Central Server
A Python script that listens for WebSocket messages. This uses the Tornado library for Python for creating the WebSocket server. This is executed in the Ubuntu web server.

I'll try to put more details as I go, but for now, I think this 10000-feet view is the better for catching up with the status logging.
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