Skip to content

Latest commit

 

History

History
77 lines (55 loc) · 2.44 KB

03_IOT_DEVICE.md

File metadata and controls

77 lines (55 loc) · 2.44 KB
Raw

AWS IoT Device for Serta MP III BLE Bed

In this section we'll create an AWS IoT thing used to control the bed using Thing Shadows. The overall IoT workflow is illusrated in the diagram below from AWS:

IoT Workflow

Shadows are are useful concept in the world of IoT for asynchronous device control usign standard protocols like MQTT and Websockets. Shadows contain the state for a thing and have two important fields, desired and reported. When the desired state is updated from an Lambda function the delta is published to he MQTT topic, the device listening on that topic sees the delta and tries to resolve it. Once resolved, the device sets the reported state of the shadow and the state is now back in sync.

Creating the device

Set environment variables:

export AWS_ACCESS_KEY_ID=YOUR_ACCESS_KEY
export AWS_SECRET_ACCESS_KEY=YOUR_SECRET_KEY
export AWS_DEFAULT_REGION=us-east-1
export IOT_ENDPOINT=$(aws iot describe-endpoint | jq -r '.endpointAddress')
export THING_NAME=iot-bed

Create the certificates:

CERT_ARN=$(aws iot create-keys-and-certificate \
  --set-as-active \
  --certificate-pem-outfile device.pem \
  --public-key-outfile device.pub \
  --private-key-outfile device-key.pem | jq -r '.certificateArn')

Create the IoT Thing:

THING_ARN=$(aws iot create-thing \
  --thing-name "${THING_NAME}" | jq -r '.thingArn')

Connect certificate to thing:

aws iot attach-thing-principal \
  --thing-name "${THING_NAME}" \
  --principal "${CERT_ARN}"

Create the policy:

aws iot create-policy \
  --policy-name "${THING_NAME}" \
  --policy-document '{"Version":"2012-10-17","Statement":[{"Action":"iot:*","Resource":"*","Effect":"Allow"}]}'

Attach the policy:

aws iot attach-principal-policy \
  --principal "${CERT_ARN}" \
  --policy-name "${THING_NAME}"

Download the root cert:

curl -o root-CA.crt https://www.symantec.com/content/en/us/enterprise/verisign/roots/VeriSign-Class%203-Public-Primary-Certification-Authority-G5.pem

To get the current shadow state:

aws iot-data get-thing-shadow \
  --thing-name iot-bed /dev/stdout | jq .

The code that connects to this shadow is in the src/iot directory.

Next we create a Lambda function that will update the thing shadow.