如何从cloudwatch事件中获取bucket名称？

Question

我正在编写一个由cloudwatch事件“createbucket”触发的lambda函数 尝试执行lambda函数时，该函数为：

import json

s3 = boto3.client('s3')

def lambda_handler(event, context):
# Get bucket name from the S3 event
print(event)

    bucket_name = event['detail']['requestParameters']['bucketName']
print(bucket_name) 

#        if record['eventName'] == "CreateBucket":
#            bucket =record['detail']['requestParameters']['bucketName']
#            print(bucket)
#            bucket_name =bucket
    # Create a bucket policy
bucket_policy =json.dumps({
    "Version": "2012-10-17",
    "Statement": [
        {
            "Sid": "MustBeEncryptedAtRest",
            "Effect": "Deny",
            "Principal": "*",
            "Action": "s3:PutObject",
            "Resource": [
                "arn:aws:s3:::{bucket_name}",
                "arn:aws:s3:::{bucket_name}/*"
            ],
            "Condition": {
                "StringNotEquals": {
                    "s3:x-amz-server-side-encryption": [
                        "AES256",
                        "aws:kms"
                    ]
                }
            }
        },
        {
            "Sid": "MustBeEncryptedInTransit",
            "Effect": "Deny",
            "Principal": "*",
            "Action": "s3:*",
            "Resource": [
                "arn:aws:s3:::{bucket_name}",
                "arn:aws:s3:::{bucket_name}/*"
            ],
            "Condition": {
                "Bool": {
                    "aws:SecureTransport": "false"
                    }
            }
        } ] })


    # Set the new policy
s3.put_bucket_policy(Bucket=bucket_name, Policy=bucket_policy)

我遇到了一个必须处理的错误

module initialization error: name 'bucket_name' is not defined 有什么想法吗？ 我必须获得createbucket事件拾取的bucket的名称，但它似乎从未传递到lambda函数。有没有办法将新bucket的名称传递给函数

编辑 我得到的新错误是

{
  "stackTrace": [
    [
      "/var/task/lambda_function.py",
      11,
      "lambda_handler",
      "bucket_name = event['detail']['requestParameters']['bucketName']"
    ]
  ],
  "errorType": "KeyError",
  "errorMessage": "'detail'"
}

CW事件配置：

  "source": [
    "aws.s3"
  ],
  "detail-type": [
    "AWS API Call via CloudTrail"
  ],
  "detail": {
    "eventSource": [
      "s3.amazonaws.com"
    ],
    "eventName": [
      "CreateBucket"
    ]
  }
}

Answer 1

编辑

除了缩进问题外，这似乎是由于使用默认Lambda事件模板时出错造成的，该模板与CloudWatch事件的语法不匹配

原创

这是一个缩进问题。s3.put_bucket_policy(Bucket=bucket_name, Policy=bucket_policy)函数调用将在lambda_handler之外执行

我已经修复了下面Lambda函数的缩进

import json
import boto3

s3 = boto3.client('s3')

def lambda_handler(event, context):
    # Get bucket name from the S3 event
    print(event)

    bucket_name = event['detail']['requestParameters']['bucketName']
    print(bucket_name) 

#        if record['eventName'] == "CreateBucket":
#            bucket =record['detail']['requestParameters']['bucketName']
#            print(bucket)
#            bucket_name =bucket
    # Create a bucket policy
    bucket_policy =json.dumps({
        "Version": "2012-10-17",
        "Statement": [
            {
                "Sid": "MustBeEncryptedAtRest",
                "Effect": "Deny",
                "Principal": "*",
                "Action": "s3:PutObject",
                "Resource": [
                    "arn:aws:s3:::{}".format(bucket_name),
                    "arn:aws:s3:::{}/*".format(bucket_name)
                ],
                "Condition": {
                    "StringNotEquals": {
                        "s3:x-amz-server-side-encryption": [
                            "AES256",
                            "aws:kms"
                        ]
                    }
                }
            },
            {
                "Sid": "MustBeEncryptedInTransit",
                "Effect": "Deny",
                "Principal": "*",
                "Action": "s3:*",
                "Resource": [
                    "arn:aws:s3:::{}".format(bucket_name),
                    "arn:aws:s3:::{}/*".format(bucket_name)
                ],
                "Condition": {
                    "Bool": {
                        "aws:SecureTransport": "false"
                        }
                }
            } ] })


    # Set the new policy
    s3.put_bucket_policy(Bucket=bucket_name, Policy=bucket_policy)