aws(學習筆記第三十二課) 深入使用cdk

• 使用cdk生成aws API Gateway+lambda以及eventbridge等等

學習內容：

• 使用aws API Gateway+lambda
• 使用event bridge練習producer和consumer

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1. 使用aws API Gateway+lambda

1.1. 以前的練習

• 以前的例子
  API Gateway + lambda這個例子中已經使用了手動創建，使用練習了aws API Gateway+lambda
• 使用cdk來創建
  這里，采用cdk的方式來創建API Gateway + lambda。
  代碼鏈接 api-cors-lambda

1.2. 使用cdk創建API Gateway + lambda

• 整體架構
  
• 代碼解析
  • 創建lambda函數

    	   base_lambda = _lambda.Function(self, 'ApiCorsLambda',handler='lambda-handler.handler',runtime=_lambda.Runtime.PYTHON_3_12,code=_lambda.Code.from_asset('lambda'))
    

    注意，這里沒有創建VPC，因為這里不需要顯示的創建VPC。
    

    • 創建API并且添加resource

              base_api = _apigw.RestApi(self, 'ApiGatewayWithCors',rest_api_name='ApiGatewayWithCors')example_entity = base_api.root.add_resource('example',default_cors_preflight_options=_apigw.CorsOptions(allow_methods=['GET', 'OPTIONS'],allow_origins=_apigw.Cors.ALL_ORIGINS)
      

      

    • 創建LambdaIntegration將API和lambda進行綁定

            example_entity_lambda_integration = _apigw.LambdaIntegration(base_lambda,proxy=False,integration_responses=[_apigw.IntegrationResponse(status_code="200",response_parameters={'method.response.header.Access-Control-Allow-Origin': "'*'"})])
      

      

    • 對API加入method

            example_entity.add_method('GET', example_entity_lambda_integration,method_responses=[_apigw.MethodResponse(status_code="200",response_parameters={'method.response.header.Access-Control-Allow-Origin': True})])
      

      

1.3. 確認cdk創建API Gateway + lambda

• 執行創建的cdk

  	cdk --require-approval never deploy
  

• 查看創建的結果

  • lambda創建結果
    

  • API創建結果
    

  • 確認API的調用URL
    

  • 訪問API的調用URL
    之后不要忘記cdk destroy
    

2. 使用event bridge練習producer和consumer

2.1. 代碼鏈接

api-eventbridge-lambda的代碼鏈接
這里主要練習使用eventbridge，進行producer和consumer的練習。

2.2. 開始練習

• 整體架構
  
• 代碼解析

  • 生成producer

    			        ## Producer Lambda#event_producer_lambda = _lambda.Function(self, "eventProducerLambda",runtime=_lambda.Runtime.PYTHON_3_12,handler="event_producer_lambda.lambda_handler",code=_lambda.Code.from_asset("lambda"))event_policy = iam.PolicyStatement(effect=iam.Effect.ALLOW, resources=['*'], actions=['events:PutEvents'])event_producer_lambda.add_to_role_policy(event_policy)
    

    這里，producer被賦予權限putEvents，因為之后要向eventbridge進行putEvents操作。
    

  • producer的處理代碼

    	def lambda_handler(event, context):eventbridge_client = boto3.client('events')request_body = event["body"]if request_body is None:request_body = ""# Structure of EventBridge Eventeventbridge_event = {'Time': datetime.datetime.now(),'Source': 'com.mycompany.myapp','Detail': request_body,'DetailType': 'service_status'}logger.info(eventbridge_event)# Send event to EventBridgeresponse = eventbridge_client.put_events(Entries=[eventbridge_event])logger.info(response)# Returns success reponse to API Gatewayreturn {"statusCode": 200,"body": json.dumps({"result": "from Producer"}),}
    

    這里，使用了boto3這個python package，AWS ?Boto3? 是亞馬遜云服務（AWS）官方提供的 Python SDK，主要用于通過代碼與 AWS 服務進行交互和管理。這里使用boto3向eventbridge進行putEvents。

  • consumer1和consumer2

    			        ## Approved Consumer1#event_consumer1_lambda = _lambda.Function(self, "eventConsumer1Lambda",runtime=_lambda.Runtime.PYTHON_3_8,handler="event_consumer_lambda.lambda_handler",code=_lambda.Code.from_asset("lambda"))event_consumer1_rule = events.Rule(self, 'eventConsumer1LambdaRule',description='Approved Transactions',event_pattern=events.EventPattern(source=['com.mycompany.myapp']))event_consumer1_rule.add_target(targets.LambdaFunction(handler=event_consumer1_lambda))## Approved Consumer2#event_consumer2_lambda = _lambda.Function(self, "eventConsumer2Lambda",runtime=_lambda.Runtime.PYTHON_3_8,handler="event_consumer_lambda.lambda_handler",code=_lambda.Code.from_asset("lambda"))event_consumer2_rule = events.Rule(self, 'eventConsumer2LambdaRule',description='Approved Transactions',event_pattern=events.EventPattern(source=['com.mycompany.myapp']))event_consumer2_rule.add_target(targets.LambdaFunction(handler=event_consumer2_lambda))
    

    consumer1和consumer2類似，就是接受到了eventbridge的event之后，進行log輸出。

    			def lambda_handler(event, context):logger.info(event)return {"statusCode": 200,"body": json.dumps({"result": "testing..."}),}
    

    

  • consumer3使用kinesisfirehose對event進行接受，并保存到S3 bucket上

    	        ## Approved Consumer3## Create S3 bucket for KinesisFirehose destinationingest_bucket = s3.Bucket(self, 'test-ngest-bucket')# Create a Role for KinesisFirehosefirehose_role = iam.Role(self, 'myRole',assumed_by=iam.ServicePrincipal('firehose.amazonaws.com'))# Create and attach policy that gives permissions to write in to the S3 bucket.iam.Policy(self, 's3_attr',policy_name='s3kinesis',statements=[iam.PolicyStatement(actions=['s3:*'],resources=['arn:aws:s3:::' + ingest_bucket.bucket_name + '/*'])],# resources=['*'])],roles=[firehose_role],)event_consumer3_kinesisfirehose = _firehose.CfnDeliveryStream(self, "consumer3-firehose",s3_destination_configuration=_firehose.CfnDeliveryStream.S3DestinationConfigurationProperty(bucket_arn=ingest_bucket.bucket_arn,buffering_hints=_firehose.CfnDeliveryStream.BufferingHintsProperty(interval_in_seconds=60),compression_format="UNCOMPRESSED",role_arn=firehose_role.role_arn))event_consumer3_rule = events.Rule(self, 'eventConsumer3KinesisRule',description='Approved Transactions',event_pattern=events.EventPattern(source=['com.mycompany.myapp']))event_consumer3_rule.add_target(targets.KinesisFirehoseStream(stream=event_consumer3_kinesisfirehose))
    

    

  • 將producer通過API Gateway進行公開

    	        # defines an API Gateway REST API resource backed by our "atm_producer_lambda" function.api = api_gw.LambdaRestApi(self, 'SampleAPI-EventBridge-Multi-Consumer',handler=event_producer_lambda,proxy=False)items = api.root.add_resource("items")items.add_method("POST")  # POST /items
    

2.3. 代碼部署的確認

接下來進行cdk deploy來確認執行效果。

• 一個producer與兩個consumer，都是lambda
  
• 第三個consumer，一個kinesisFireHose
  
• API的producer
  

2.4. 對部署進行測試

• 對API進行測試調用
  返回了正常的結果。這里，需要對請求正文request body一定要設定參數這里設置如下。

  {"item1":"123","item2":"234"}
  

  使用API調用，之后啟動producer的lamdba，向eventbridge進行putEvents。
  
• 對consumer1和consumer2進行確認
  
• 對consumer3進行確認
  這里主要是對S3 bucket進行確認。可以看到，
  producer -> event -> eventbridge -> consumer3 -> kinesis firehose -> S3 bucket
  最后cdk destroy。