Tạo hàm handle_order Lambda

Trong bước này, chúng ta sẽ tạo một hàm handle_order Lambda mới bằng cách sử dụng mẫu SAM.

Chuẩn bị

  1. Mở template.yaml trong mã nguồn bạn đã tải xuống trước đó.

    • Bình luận khối mã này.

      # BookApiDeployment:
#   Type: AWS::ApiGateway::Deployment
#   Properties:
#     RestApiId: !Ref BookApi
#   DependsOn:
#     - BookApiGet
#     - BookApiCreate
#     - BookApiDelete
#     - LoginApi
#     - RegisterApi
#     - ConfirmApi
#     - FcjCheckoutOrderApi
#     - FcjOrderManagementApi

# BookApiStage:
#   Type: AWS::ApiGateway::Stage
#   Properties:
#     RestApiId: !Ref BookApi
#     StageName: !Ref stage
#     DeploymentId: !Ref BookApiDeployment

      CreateHandleOrderFunction

  2. Chạy các lệnh dưới đây.

    sam build
sam validate
sam deploy

    CreateHandleOrderFunction

Tạo hàm FcjHandleOrder

  1. Mở template.yaml trong mã nguồn bạn đã tải xuống trước đó.

    • Thêm các đoạn mã sau để tạo hàm FcjHandleOrder.

      handleOrderPathPart:
  Type: String
  Default: handle

      CreateHandleOrderFunction

      FcjHandleOrderResource:
  Type: AWS::ApiGateway::Resource
  Properties:
    RestApiId: !Ref BookApi
    ParentId: !Ref FcjCheckoutOrderResource
    PathPart: !Ref handleOrderPathPart

FcjHandleOrderFunction:
  Type: AWS::Serverless::Function
  Properties:
    CodeUri: fcj-book-shop/handle_order
    Handler: handle_order.lambda_handler
    Runtime: python3.11
    FunctionName: handle_order
    Environment:
      Variables:
        ORDER_TABLE_NAME: !Ref orderTable
        SQS_QUEUE_URL: !Ref checkoutQueueUrl
    Architectures:
      - x86_64
    Policies:
      - Statement:
          - Sid: VisualEditor0
            Effect: Allow
            Action:
              - dynamodb:PutItem
              - dynamodb:BatchWriteItem
            Resource:
              - !Sub "arn:aws:dynamodb:${AWS::Region}:${AWS::AccountId}:table/${orderTable}"
          - Sid: VisualEditor1
            Effect: Allow
            Action:
              - sqs:*
            Resource:
              - !Sub "arn:aws:sqs:${AWS::Region}:${AWS::AccountId}:${checkoutQueueName}"

FcjHandleOrderApiOptions:
  Type: AWS::ApiGateway::Method
  Properties:
    HttpMethod: OPTIONS
    RestApiId: !Ref BookApi
    ResourceId: !Ref FcjHandleOrderResource
    AuthorizationType: NONE
    Integration:
      Type: MOCK
      IntegrationResponses:
        - StatusCode: "200"
          ResponseParameters:
            method.response.header.Access-Control-Allow-Origin: "'*'"
            method.response.header.Access-Control-Allow-Methods: "'OPTIONS,POST,GET,DELETE'"
            method.response.header.Access-Control-Allow-Headers: "'Content-Type,X-Amz-Date,Authorization,X-Api-Key,X-Amz-Security-Token'"
    MethodResponses:
      - StatusCode: "200"
        ResponseParameters:
          method.response.header.Access-Control-Allow-Origin: true
          method.response.header.Access-Control-Allow-Methods: true
          method.response.header.Access-Control-Allow-Headers: true

FcjHandleOrderApi:
  Type: AWS::ApiGateway::Method
  Properties:
    HttpMethod: POST
    RestApiId: !Ref BookApi
    ResourceId: !Ref FcjHandleOrderResource
    AuthorizationType: NONE
    Integration:
      Type: AWS_PROXY
      IntegrationHttpMethod: POST # For Lambda integrations, you must set the integration method to POST
      Uri: !Sub >-
        arn:aws:apigateway:${AWS::Region}:lambda:path/2015-03-31/functions/${FcjHandleOrderFunction.Arn}/invocations
    MethodResponses:
      - StatusCode: "200"
        ResponseParameters:
          method.response.header.Access-Control-Allow-Origin: true
          method.response.header.Access-Control-Allow-Methods: true
          method.response.header.Access-Control-Allow-Headers: true

FcjHandleOrderApiInvokePermission:
  Type: AWS::Lambda::Permission
  Properties:
    FunctionName: !Ref FcjHandleOrderFunction
    Action: lambda:InvokeFunction
    Principal: apigateway.amazonaws.com
    SourceAccount: !Ref "AWS::AccountId"

      CreateHandleOrderFunction

  2. Cấu trúc thư mục như sau.

    fcj-book-shop-sam-ws3
├── fcj-book-shop
│   ├── checkout_order
│   │   └── checkout_order.py
│   ├── order_management
│   │   └── order_management.py
│   ├── handle_order
│   │   └── handle_order.py
│   ├── ...
│
└── template.yaml

    • Tạo thư mục handle_order trong thư mục fcj-book-shop-sam-ws6/fcj-book-shop/.

    • Tạo tệp handle_order.py và sao chép mã sau vào đó.

      import json
import boto3
import os

headers = {
    "Content-Type": "application/json",
    "Access-Control-Allow-Origin": "*",
    "Access-Control-Allow-Methods": "OPTIONS,POST,GET,DELETE",
    "Access-Control-Allow-Headers": "Content-Type,X-Amz-Date,Authorization,X-Api-Key,X-Amz-Security-Token"
}

dynamodb = boto3.resource('dynamodb')
sqs = boto3.client('sqs')

# Define the DynamoDB table name and SQS queue URL
table_name = os.getenv('ORDER_TABLE_NAME')
queue_url = os.getenv('SQS_QUEUE_URL')


def lambda_handler(event, context):
    # Get product body info from the event
    products = json.loads(event['body'])
    books = products['books']
    receipt_handle = products['receiptHandle']

    # Write product info to DynamoDB
    table = dynamodb.Table(table_name)
    try:
        for book in books:
            data = {
                'id': products['id'],
                'book_id': book['id'],
                'name': book['name'],
                'qty': book['qty'],
                'price': str(products['price'])
            }

            table.put_item(Item=data)
    except Exception as e:
        print(f"Error writing to DynamoDB: {e}")
        raise Exception(f"Error writing to DynamoDB: {e}")

    # Delete message in SQS
    try:
        sqs.delete_message(
            QueueUrl=queue_url,
            ReceiptHandle=receipt_handle
        )
    except Exception as e:
        print(f"Error deleting message from SQS: {e}")
        raise Exception(f"Error deleting message from SQS: {e}")

    return {
        'statusCode': 200,
        'headers': headers,
        'body': json.dumps('Order processed successfully')
    }

      CreateHandleOrderFunction

  3. Bỏ bình luận khối mã này.

    BookApiDeployment:
  Type: AWS::ApiGateway::Deployment
  Properties:
    RestApiId: !Ref BookApi
  DependsOn:
    - BookApiGet
    - BookApiCreate
    - BookApiDelete
    - LoginApi
    - RegisterApi
    - ConfirmApi
    - FcjCheckoutOrderApi
    - FcjOrderManagementApi
    - FcjHandleOrderApi

BookApiStage:
  Type: AWS::ApiGateway::Stage
  Properties:
    RestApiId: !Ref BookApi
    StageName: !Ref stage
    DeploymentId: !Ref BookApiDeployment

    CreateHandleOrderFunction

  4. Chạy các lệnh dưới đây.

    sam build
sam validate
sam deploy

    CreateHandleOrderFunction

Kiểm tra việc tạo

  1. Mở Amazon API Gateway console.

    • Nhấp vào fcj-serverless-api. CreateHandleOrderFunction
    • Nhấp vào Resources trên menu bên trái.
    • Kiểm tra /handle vừa được tạo. CreateHandleOrderFunction

  2. Mở Amazon Lambda console.

    • Nhấp vào Functions trên menu bên trái.
    • Chọn hàm handle_order. CreateHandleOrderFunction
    • Tại trang handle_order, kiểm tra hàm vừa được tạo. CreateHandleOrderFunction