使用Python处理Lambda中的S3 Bucket Trigger事件

Question

AWS Lambda处理程序具有签名

def lambda_handler(event, context):

但是，当触发器是S3 Bucket接收put时，我找不到有关事件结构的任何文档

我认为它可能在s3控制台中定义，但在那里找不到。

有人有任何线索吗？

Answer 1

从S3到Lambda函数的事件将采用json格式，如下所示，

{  
   "Records":[  
      {  
         "eventVersion":"2.0",
         "eventSource":"aws:s3",
         "awsRegion":"us-east-1",
         "eventTime":The time, in ISO-8601 format, for example, 1970-01-01T00:00:00.000Z, when S3 finished processing the request,
         "eventName":"event-type",
         "userIdentity":{  
            "principalId":"Amazon-customer-ID-of-the-user-who-caused-the-event"
         },
         "requestParameters":{  
            "sourceIPAddress":"ip-address-where-request-came-from"
         },
         "responseElements":{  
            "x-amz-request-id":"Amazon S3 generated request ID",
            "x-amz-id-2":"Amazon S3 host that processed the request"
         },
         "s3":{  
            "s3SchemaVersion":"1.0",
            "configurationId":"ID found in the bucket notification configuration",
            "bucket":{  
               "name":"bucket-name",
               "ownerIdentity":{  
                  "principalId":"Amazon-customer-ID-of-the-bucket-owner"
               },
               "arn":"bucket-ARN"
            },
            "object":{  
               "key":"object-key",
               "size":object-size,
               "eTag":"object eTag",
               "versionId":"object version if bucket is versioning-enabled, otherwise null",
               "sequencer": "a string representation of a hexadecimal value used to determine event sequence, 
                   only used with PUTs and DELETEs"            
            }
         }
      },
      {
          // Additional events
      }
   ]
}

这是aws文档的链接，可以指导您。 http://docs.aws.amazon.com/lambda/latest/dg/with-s3-example.html

Answer 2

我认为您最简单的方法就是快速实验：

1. 使用控制台创建存储桶
2. 使用控制台创建由put放入存储区触发的lambda
3. 确保选择默认执行角色，以便创建cloudwatch日志
4. lambda函数在调用时只需要“print（event）”，然后记录
5. 将对象保存到存储桶

然后，您将在日志中看到事件结构 - 它非常自我解释。

Answer 3

请参阅此URL以获取事件消息结构： http ： //docs.aws.amazon.com/AmazonS3/latest/dev/notification-content-structure.html