在AWS IoT和Lambda架构中,有时需要使用SQS(简单队列服务),以增加系统的可伸缩性和健壮性。以下是使用AWS IoT和Lambda与SQS的示例代码:
在AWS IoT中创建一个主题。
在Lambda中创建一个函数,该函数将使用SNS(简单通知服务)向主题发布消息。
import boto3
def lambda_handler(event, context):
sns = boto3.client('sns')
topic_arn = "arn:aws:sns:us-east-1:123456789012:IoT_topic"
sns.publish(TopicArn=topic_arn,Message="Hello from Lambda!")
在Lambda中创建另一个函数,该函数将从SNS主题订阅消息并将其写入SQS队列。
import boto3
def lambda_handler(event, context):
sqs = boto3.client('sqs')
queue_url = "https://sqs.us-east-1.amazonaws.com/123456789012/IoT_queue"
messages = sqs.receive_message(QueueUrl=queue_url)
for message in messages['Messages']:
print(message['Body'])
sqs.delete_message(QueueUrl=queue_url, ReceiptHandle=message['ReceiptHandle'])
创建一个IAM角色以允许Lambda访问SNS和SQS,然后将此角色与Lambda函数关联。
{
"Version": "2012-10-17",
"Statement": [
{
"Effect": "Allow",
"Action": [
"sns:Publish",
"sqs:ReceiveMessage",
"sqs:DeleteMessage"
],
"Resource": [
"arn:aws:sns:us-east-1:123456789012:IoT_topic",
"https://sqs.us-east-1.amazonaws.com/123456789012/IoT_queue"
]
}
]
}