3. Architecture and Design

The API layer consists of the following AWS resources:

1. API Gateway,
2. Lambda,
3. Systems Manager,
4. ECR,
5. IAM Role.

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3.1 Explanation of the resources selection

Considering cost-effectiveness, operational simplicity and scalability, security and modularity, here are the reasons for selecting these resources:

1. API Gateway: to avoid networking configuration and optimize cost. The free tier consists of one million API calls received for HTTP APIs for up to 12 months¹.
2. Lambda: to reduce operational complexity and to avoid unnecessary expenses associated with maintaining a hot startup environment, also for easy scalability.
3. Systems Manager: its Parameter Store provides a cost-free alternative for storing secrets by using standard parameter and throughput, in contrast to Secret Manager².
4. ECR: to minimizing storage and transfer costs. Free storage up to 50 GB per month. Data transfer from Docker into ECR and from ECR to AWS Lambda is free ³.
5. IAM Role: to implements the Principle of Least Leverage.

1:https://aws.amazon.com/api-gateway/pricing/
2:https://aws.amazon.com/systems-manager/pricing/
3:https://aws.amazon.com/ecr/pricing/

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3.2 Architecture Diagramm

3.3 Flow Chart