The project uses FastAPI (https://fastapi.tiangolo.com/) on AWS Lambda function with API GW, and the infrastructure is built using Terraform.
This configuration has been tested "us-east-1" region
1 - Run docker desktop - it is used by terraform to install pip libs and create lambda.zip
2 - export AWS Credentials to CLI
3 -
terraform init
terraform plan
terraform apply [-auto-approve]
AWS DynamoDB is used as the User and Order Service database - Single-Table Design Pattern is used.
Single-table in DynamoDB is to retrieve multiple, heterogenous item types using a single request.
Data access patterns can be handled with as few requests to DynamoDB as possible.
```
Users have a one-to-many relationship with Orders.
```
1 UserService - API Gateway REST API with Proxy Lambda function.
The UserService exposes the following endpoints to maintain and manage users.
/add-user/{dict} - The email address and the username must always be unique - A duplicate record will result in Transaction Canceled error.
curl -X 'POST' \
'https://{API_GW_ID}.execute-api.us-east-1.amazonaws.com/dev/add_user/' \
-H 'accept: application/json' \
-H 'Content-Type: application/json' \
-d '{
"email": "[email protected]",
"name": "Test Name",
"username": "test111"
}'
{
"message": "User test111 with added successfully"
}
/users/{username} - Prints the User Information
curl -X 'GET' \
'https://xllrwe5j5k.execute-api.us-east-1.amazonaws.com/dev/users/test111' \
-H 'accept: application/json'
/edit-address/{username}{address_dict} - Add/Edit/Update {username} address
curl -X 'POST' \
'https://xllrwe5j5k.execute-api.us-east-1.amazonaws.com/dev/edit-address?username=test111&new_address=124%20Street%20Akl%20NZ' \
-H 'accept: application/json' \
-d ''
2 OrderService - API Gateway REST API with Proxy Lambda function.
The OrderService maintains and manages order data.
This service exposes the following endpoints.
/orders/{username} - Returns existing order information.
curl -X 'GET' \
'https://{API_GW_ID}.execute-api.us-east-1.amazonaws.com/dev/orders/?username=john' \
-H 'accept: application/json'
Returns
"message": "orders fetched successfully",
"data": [
{
"SK": "CUSTOMER#john",
"PK": "CUSTOMER#john",
"Email": "[email protected]",
"Username": "john",
"Name": "john smith"
},
{
"NumberItems": 2,
"SK": "#ORDER#2UJT4m2UkBAWG7DHDLfkXxbMN04",
"Status": "PLACED",
"Amount": 5.5,
"PK": "CUSTOMER#john",
"OrderId": "2UJT4m2UkBAWG7DHDLfkXxbMN04",
"CreatedAt": "2023-08-21T22:21:34.811747"
}
]
}
/orders/{dict} - Create new order
curl -X 'POST' \
'https://{API_GW_ID}.execute-api.us-east-1.amazonaws.com/dev/orders/' \
-H 'accept: application/json' \
-H 'Content-Type: application/json' \
-d '{
"amount": 5.5,
"numItems": 2,
"username": "john"
}'
Returns
{
"message": "Order placed successfully",
"success": true,
"data": {
"PK": "CUSTOMER#john",
"SK": "#ORDER#2UJuYiRSoBMgAiXg7jBp0V0UqxU",
"OrderId": "2UJuYiRSoBMgAiXg7jBp0V0UqxU",
"CreatedAt": "2023-08-22T02:07:33.696174",
"Status": "PLACED",
"Amount": 5.5,
"NumberItems": 2
}
}
/orders/{order_id}/{dict} - Update order status
curl -X 'PUT' \
'https://{API_GW_ID}.execute-api.us-east-1.amazonaws.com/dev/orders/2UJuYiRSoBMgAiXg7jBp0V0UqxU' \
-H 'accept: application/json' \
-H 'Content-Type: application/json' \
-d '{
"username": "john",
"status": "CANCEL"
}'
Returns
{
"message": "Order updated successfully",
"success": true,
"data": {
"UpdatedAt": "2023-08-22T02:09:03.577842",
"NumberItems": 2,
"SK": "#ORDER#2UJuYiRSoBMgAiXg7jBp0V0UqxU",
"Status": "CANCEL",
"Amount": 5.5,
"PK": "CUSTOMER#john",
"OrderId": "2UJuYiRSoBMgAiXg7jBp0V0UqxU",
"CreatedAt": "2023-08-22T02:07:33.696174"
}
}
3 NotificationService
The notification service is built using the AWS Eventbridge Pipes Service - The Eventbridge Pipe uses the DynamoDB Stream NEW_IMAGE as Source and invokes the Lambda function when a new order is placed - The Notification is sent to a SNS Topic
The Lambda Powertools library is used in the lambda function code to structured logging and tracing Lambda Powertools Lib
Alarms - AWS Cloudwatch Alarms are created for the "Error" Metric Filter on the Lambda Log Groups - When errors are logged, An alarm will triggered to the SNS monitoring Topic.
AWS Code pipeline and Codebuild services are used to build and deploy the project.
The API gateway, Lamda and Dynamodb services are designed for massive scaling.