Chalice Todo API

A serverless Todo API built with AWS Chalice, using DynamoDB for storage and deployed with CloudFormation.

• Create, read, update, and delete Todo items
• Serverless architecture using AWS Lambda and API Gateway
• Data persistence with Amazon DynamoDB
• Infrastructure as Code using CloudFormation

• Python 3.7 or higher
• AWS CLI configured with appropriate credentials
• AWS account with permissions to create Lambda, API Gateway, IAM roles, and DynamoDB resources

1. Clone this repository
2. Install dependencies:

pip install -r requirements.txt

To run the application locally:

chalice local

This will start a local development server at http://localhost:8000.

To deploy the application to AWS:

./deploy.sh

This will:

1. Generate the Chalice CloudFormation template
2. Merge it with the additional resources defined in aws_stack.yaml
3. Deploy the merged stack to AWS
4. Output the API endpoint URL and DynamoDB table name

The application uses a separate CloudFormation template (aws_stack.yaml) to define additional resources:

• DynamoDB table for storing Todo items

This template is merged with the Chalice-generated template during deployment using Chalice's built-in --merge-template option.

To generate a CloudFormation template without deploying:

chalice package --stage dev --merge-template aws_stack.yaml --template-format json .chalice/cloudformation

This will create a merged CloudFormation template in the .chalice/cloudformation directory that you can deploy using the AWS CloudFormation console or AWS CLI.

To deploy using the merged CloudFormation template:

aws cloudformation deploy --template-file .chalice/cloudformation/sam.json --stack-name todo-app --capabilities CAPABILITY_IAM

• GET / - Get API information
• GET /todos - List all todos
• POST /todos - Create a new todo
• GET /todos/{todo_id} - Get a specific todo
• PUT /todos/{todo_id} - Update a todo
• DELETE /todos/{todo_id} - Delete a todo

curl -X POST https://your-api-id.execute-api.region.amazonaws.com/api/todos \
  -H "Content-Type: application/json" \
  -d '{"title": "Learn AWS Chalice", "description": "Build a serverless API with Chalice"}'

curl https://your-api-id.execute-api.region.amazonaws.com/api/todos

curl https://your-api-id.execute-api.region.amazonaws.com/api/todos/{todo_id}

curl -X PUT https://your-api-id.execute-api.region.amazonaws.com/api/todos/{todo_id} \
  -H "Content-Type: application/json" \
  -d '{"title": "Updated title", "completed": true}'

curl -X DELETE https://your-api-id.execute-api.region.amazonaws.com/api/todos/{todo_id}

To remove all AWS resources created by this application:

chalice delete

Or if you deployed using CloudFormation:

aws cloudformation delete-stack --stack-name todo-app