With this project, you can ask Alexa, if your door is open. It uses a magnetic sensor attached to ESP8266 to do detect if the door is open. Alexa skill can access the information using AWS Lambda function, Azure REST API, and SignalR via Raspberry Pi. When a user asks Alexa the state of the door, it invokes a lambda function. The function calls a REST API method hosted in Azure. The REST API method uses SignalR technology to query Raspberry Pi, which in turn requests that information from ESP8266.
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