How to add AWS IoT provisioning template in Cloudformation template / CDK

Configuring AWS IoT devices using AWS CloudFormation or AWS CDK typically involves creating and managing IoT-related resources, including device shadows, certificates, policies, and rules. The following sections outline steps and examples for adding IoT configurations to CloudFormation templates and AWS CDK.

Adding AWS IoT Configurations with AWS CloudFormation

1. Defining an IoT Policy

First, define an IoT policy in the CloudFormation template to specify the permissions for the device.

yaml
Resources:
  IoTPolicy:
    Type: AWS::IoT::Policy
    Properties: 
      PolicyDocument:
        Version: "2012-10-17"
        Statement:
          - Effect: "Allow"
            Action: "iot:*"
            Resource: "*"

2. Creating an IoT Device Certificate

Next, create an IoT device certificate using CloudFormation and attach it to the previously defined policy.

yaml
  IoTDeviceCertificate:
    Type: AWS::IoT::Certificate
    Properties: 
      Status: ACTIVE
      CACertificatePem: "-----BEGIN CERTIFICATE-----\n...\n-----END CERTIFICATE-----"
      CertificateSigningRequest: "-----BEGIN CERTIFICATE REQUEST-----\n...\n-----END CERTIFICATE REQUEST-----"

3. Attaching the Policy to the Certificate

Then, attach the policy to the newly created certificate.

yaml
  PolicyAttachment:
    Type: AWS::IoT::PolicyPrincipalAttachment
    Properties: 
      PolicyName: !Ref IoTPolicy
      Principal: !Ref IoTDeviceCertificate

Adding AWS IoT Configurations with AWS CDK

1. Installing CDK Libraries

First, verify that AWS CDK tools and the necessary libraries are installed.

bash
npm install -g aws-cdk
npm install @aws-cdk/aws-iot

2. Creating an IoT Policy

Create an IoT policy using AWS CDK.

typescript
import * as iot from '@aws-cdk/aws-iot';

const stack = new cdk.Stack(app, 'IoTStack');

const policy = new iot.CfnPolicy(stack, 'Policy', {
  policyDocument: {
    Version: '2012-10-17',
    Statement: [{
      Effect: 'Allow',
      Action: 'iot:*',
      Resource: '*'
    }],
  }
});

3. Creating a Device Certificate

Create an IoT device certificate in CDK and attach it to the policy.

typescript
const cert = new iot.CfnCertificate(stack, 'Certificate', {
  status: 'ACTIVE',
  // This typically requires a Base64-encoded CSR or CA certificate, which is omitted for brevity.
});

new iot.CfnPolicyPrincipalAttachment(stack, 'PolicyAttachment', {
  policyName: policy.ref,
  principal: cert.attrArn
});

Conclusion

By following these steps, you can configure AWS IoT devices in AWS CloudFormation or AWS CDK. CloudFormation enables direct definition of configurations in YAML or JSON templates, while CDK allows developers to write and manage AWS resources using familiar programming languages, offering greater flexibility and maintainability. Both approaches are effective, and the choice depends on your project requirements and team expertise.