Working with SNS > Update Unicorn Management Service

Update Unicorn Management Service

After creating SNS Topic and subscriptions according to the architecture:

Working with SNS

First we grant IAM permission to Lambda

Updated SAM template wild-rydes-async-messaging/lab-1/template.yaml

- SNSPublishMessagePolicy:
    TopicName: !GetAtt RideCompletionTopic.TopicName

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Next we have to give Amazon SNS topic ARN to Lambda.

Keep updating SAM template wild-rydes-async-messaging/lab-1/template.yaml

TOPIC_ARN: !Ref RideCompletionTopic

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Then we will update the Lambda function to call Amazon SNS

Open the file wild-rydes-async-messaging/lab-1/unicorn-management-service/app.py

sns = boto3.client('sns', config=config)

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Next, we will put the item to DynamoDB

    response = sns.publish(
        TopicArn=TOPIC_ARN,
        Message=json.dumps(request),
        MessageAttributes = {
            'fare': {
                'DataType': 'Number',
                'StringValue': str(request['fare'])
            },
            'distance': {
                'DataType': 'Number',
                'StringValue': str(request['distance'])
            }
        }
    )

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Update the template with the following command:

cd ~/environment/wild-rydes-async-messaging/lab-1
Sam build

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After updating, we deploy with the following command:

sam deploy

Working with SNS