python中aws sns事件数据的json解析

Question

我可以使用

def lambda_handler(event, context):
    message = event['Records'][0]['Sns']['Message']
    print("From SNS: " + message)

输出：

{
    "Records": [
        {
            "eventVersion": "2.0",
            "eventSource": "aXXXX",
            "awsRegion": "XXXXX",
            "eventTime": "2016-03-09T12:24:19.255Z",
            "eventName": "ObjectCreated:Put",
            "userIdentity": {
                "principalId": "AWS:XXXXXXXXXXX"
            },
            "requestParameters": {
                "sourceIPAddress": "xxx.xxx.xx.xx"
            },
            "responseElements": {
                "x-amz-request-id": "XXXX",
                "x-amz-id-2": "XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX"
            },
            "s3": {
                "s3SchemaVersion": "1.0",
                "configurationId": "xxx-xxx-xxx",
                "bucket": {
                    "name": "bucketname",
                    "ownerIdentity": {
                        "principalId": "XXXXXX"
                    },
                    "arn": "arn:aws:s3:::xxxxx"
                },
                "object": {
                    "key": "index.js",
                    "size": 7068,
                    "eTag": "xxxx",
                    "sequencer": "0000000000"
                }
            }
        }
    ]
}

我无法进一步分析和获取awsRegion、Records.s3.bucket.name和Records.s3.object.key的值。

我试过bucketname = message['Records'][0]['s3']['bucket']['name']。 获取错误类型错误：字符串索引必须是整数

Answer 1

我正试图在node.js中做同样的事情。我误以为事件传递的是JSON而不是字符串。我补充道：

var message = event.Records[0].Sns.Message;
console.log('Message received from SNS:', message);
var bleh=JSON.parse(event.Records[0].Sns.Message);
var blah = bleh.Records[0].s3.bucket.name;
console.log('Bucket Name:', blah);

它最终踢出了正确的桶名。

Answer 2

我认为您可能需要加载json：

import json

def lambda_handler(event, context):
    message = event['Records'][0]['Sns']['Message']
    parsed_message = json.loads(message)
    print(parsed_message['Records'][0]['s3']['bucket']['name'])

给我

u'bucketname'

或者你是在你的职责之外的某个地方工作？