AWS Lambda 事件到 python 字典

Question

I am trying to convert event json from aws lambda function to python dictionary to that I can the event type and cluster identifier but I am getting an error which i am not able to resolve

下面是我的代码和错误

import json
st = """
{
   "Records":[
      {
         "EventSource":"aws:sns",
         "EventVersion":"1.0",
         "EventSubscriptionArn":"arn:aws:sns:us-east-2:427128480143:terraform-redshift-sns-topic:cbdfec04-7502-4509-9954-435e2ddc5e3c",
         "Sns":{
            "Type":"Notification",
            "MessageId":"fecb7b39-a861-5450-9179-23d0ce68f268",
            "TopicArn":"arn:aws:sns:us-east-2:427128480243:terraform-redshift-sns-topic",
            "Subject":"AmazonRedshiftINFO - Cluster Created",
            "Message":"{\"Event Source\":\"cluster\",\"Resource\":\"qa-redshift-cluster\",\"Event Time\":\"2021-04-08 20:12:57.466\",\"Identifier Link\":\"https://console.aws.amazon.com/redshift/home?region=us-east-2#cluster-details:cluster=qa-redshift-cluster \",\"Severity\":\"INFO\",\"Category\":[\"Management\"],\"About this Event\":\"http://docs.aws.amazon.com/redshift/latest/mgmt/working-with-event-notifications.html#REDSHIFT-EVENT-2000 \",\"Event Message\":\"Amazon Redshift cluster \\'qa-redshift-cluster\\' has been created at 2021-04-08 20:12 UTC and is ready for use.\"}",
            "Timestamp":"2021-04-08T20:12:57.905Z",
            "SignatureVersion":"1",
            "Signature":"jS2AK8hf/rebeXMsfFw0DJx+788w+RiDTXyAbLNZzYdE5Mlhi6GRRIns8VaAJZc5otXkkhGshvgvuE0JsUiOhXBccGEJY6Z+lhx6cLSQoEdQB0DRfwltWKOfpQ88LZXJuKCxYcsPL3y5veBdjJqwjdBZtcVYV9BYRhQvT6q/0MpDcJeOYzMkdpR2ULX5B7GasZ3AV0WbKxIjjzFSd3GNud2m85obRrB//NHQwqN6ydvg7PaN/sXuyJjmguRok27O6YNkIqzKjC4JxDbTl4BwyIbck59edbHC5kxmfpoc/RqjF/kUGaqnf0HYOUuMfDT85+9wYVz8vFFER1v3NnKRLA==",
            "SigningCertUrl":"https://sns.us-east-2.amazonaws.com/SimpleNotificationService-010a507c1833636cd94bdd98bd93083a.pem",
            "UnsubscribeUrl":"https://sns.us-east-2.amazonaws.com/?Action=Unsubscribe&SubscriptionArn=arn:aws:sns:us-east-2:427128480243:terraform-redshift-sns-topic:cbdfec04-7502-4509-9954-435e7ddc5e3c",
            "MessageAttributes":{
               
            }
         }
      }
   ]
}
"""

data1 = json.loads(st)
print(type(data1))
print(data1)

data1 = json.loads(st)
print(type(data1))
print(data1)


{'Records': [{'EventSource': 'aws:sns', 'EventVersion': '1.0', 'EventSubscriptionArn': 'arn:aws:sns:us-east-2:427128480243:terraform-redshift-sns-topic:cbdfec04-7502-4509-9954-435e1ddc5e3c', 'Sns': {'Type': 'Notification', 'MessageId': 'fecb7b39-a861-5450-9189-23d0ce68f268', 'TopicArn': 'arn:aws:sns:us-east-2:427128480243:terraform-redshift-sns-topic', 'Subject': '[Amazon Redshift INFO] - Cluster Created', 'Message': '{"Event Source":"cluster","Resource":"qa-redshift-cluster","Event Time":"2021-04-08 20:12:57.466","Identifier Link":"https://console.aws.amazon.com/redshift/home?region=us-east-2#cluster-details:cluster=qa-redshift-cluster ","Severity":"INFO","Category":["Management"],"About this Event":"http://docs.aws.amazon.com/redshift/latest/mgmt/working-with-event-notifications.html#REDSHIFT-EVENT-2000 ","Event Message":"Amazon Redshift cluster \'qa-redshift-cluster\' has been created at 2021-04-08 20:12 UTC and is ready for use."}', 'Timestamp': '2021-04-08T20:12:57.905Z', 'SignatureVersion': '1', 'Signature': 'jS2AK8hf/rebeXMsfFw0DJx+788w+RiDTXyAbLNZzYdE5Mlhi6GRRIns8VaAJZc5otXkkhGshvgvuE0JsUiOhXBccGEJY6Z+lhx6cLSQoEdQB0DRfwltWKOfpQ88LZXJuKCxYcsPL3y5veBdjJqwjdBZtcVYV9BYRhQvT6q/0MpDcJeOYzMkdpR2ULX5B7GasZ3AV0WbKxIjjzFSd3GNud2m85obRrB//NHQwqN6ydvg7SaN/sXuyJjmguRok27O6YNkIqzKjC4JxDbTl4BwyIbck59edbHC5kxmfpoc/RqjF/kUGaqnf0HYOUuMfDT85+9wYVz8vFFER1v3NnKRLA==', 'SigningCertUrl': 'https://sns.us-east-2.amazonaws.com/SimpleNotificationService-010a507c1833636cd94bdb98bd93083a.pem', 'UnsubscribeUrl': 'https://sns.us-east-2.amazonaws.com/?Action=Unsubscribe&SubscriptionArn=arn:aws:sns:us-east-2:427128480243:terraform-redshift-sns-topic:cbdfec04-7502-4509-9954-435e1ddc5e3c', 'MessageAttributes': {}}}]}

错误

Traceback (most recent call last):
  File "/home/deepak/PycharmProjects/TerraformSeriousProject/boto3Examples/src/test.py", line 29, in <module>
    data1 = json.loads(st)
  File "/usr/lib/python3.8/json/__init__.py", line 357, in loads
    return _default_decoder.decode(s)
  File "/usr/lib/python3.8/json/decoder.py", line 337, in decode
    obj, end = self.raw_decode(s, idx=_w(s, 0).end())
  File "/usr/lib/python3.8/json/decoder.py", line 353, in raw_decode
    obj, end = self.scan_once(s, idx)
json.decoder.JSONDecodeError: Expecting ',' delimiter: line 13 column 26 (char 520)

我使用https://jsonformatter.curiousconcept.com/#工具格式化 json

Answer 1

在 Python 中像这样加载，您需要将Message行上的反斜杠加倍。 您当前拥有的斜线将用于创建字符串。 您可以通过打印st来看到这一点

但是，更好的方法是不要将st作为字符串而是字典（即删除三引号），那么您根本不需要在这里搞乱 json 库

st = {
    "Records":[
        {
            "EventSource":"aws:sns",
            "EventVersion":"1.0",
            "EventSubscriptionArn":"arn:aws:sns:us-east-2:427128480143:terraform-redshift-sns-topic:cbdfec04-7502-4509-9954-435e2ddc5e3c",
            "Sns":{
                "Type":"Notification",
                "MessageId":"fecb7b39-a861-5450-9179-23d0ce68f268",
                "TopicArn":"arn:aws:sns:us-east-2:427128480243:terraform-redshift-sns-topic",
                "Subject":"AmazonRedshiftINFO - Cluster Created",
                "Message":"{\"Event Source\":\"cluster\",\"Resource\":\"qa-redshift-cluster\",\"Event Time\":\"2021-04-08 20:12:57.466\",\"Identifier Link\":\"https://console.aws.amazon.com/redshift/home?region=us-east-2#cluster-details:cluster=qa-redshift-cluster
    \",\"Severity\":\"INFO\",\"Category\":[\"Management\"],\"About this Event\":\"http://docs.aws.amazon.com/redshift/latest/mgmt/working-with-event-notifications.html#REDSHIFT-EVENT-2000 \",\"Event Message\":\"Amazon Redshift cluster \\'qa-redshift-cluster\\' ha
    s been created at 2021-04-08 20:12 UTC and is ready for use.\"}",
                "Timestamp":"2021-04-08T20:12:57.905Z",
                "SignatureVersion":"1",
                "Signature":"jS2AK8hf/rebeXMsfFw0DJx+788w+RiDTXyAbLNZzYdE5Mlhi6GRRIns8VaAJZc5otXkkhGshvgvuE0JsUiOhXBccGEJY6Z+lhx6cLSQoEdQB0DRfwltWKOfpQ88LZXJuKCxYcsPL3y5veBdjJqwjdBZtcVYV9BYRhQvT6q/0MpDcJeOYzMkdpR2ULX5B7GasZ3AV0WbKxIjjzFSd3GNud2m85obRrB//NHQwqN6ydv
    g7PaN/sXuyJjmguRok27O6YNkIqzKjC4JxDbTl4BwyIbck59edbHC5kxmfpoc/RqjF/kUGaqnf0HYOUuMfDT85+9wYVz8vFFER1v3NnKRLA==",
                "SigningCertUrl":"https://sns.us-east-2.amazonaws.com/SimpleNotificationService-010a507c1833636cd94bdd98bd93083a.pem",
                "UnsubscribeUrl":"https://sns.us-east-2.amazonaws.com/?Action=Unsubscribe&SubscriptionArn=arn:aws:sns:us-east-2:427128480243:terraform-redshift-sns-topic:cbdfec04-7502-4509-9954-435e7ddc5e3c",
                "MessageAttributes":{
                }
            }
        }
]
}
print(st['Records'][0]['Sns']['Message'])
{"Event Source":"cluster","Resource":"qa-redshift-cluster","Event Time":"2021-04-08 20:12:57.466","Identifier Link":"https://console.aws.amazon.com/redshift/home?region=us-east-2#cluster-details:cluster=qa-redshift-cluster ","Severity":"INFO","Category":["Management"],"About this Event":"http://docs.aws.amazon.com/redshift/latest/mgmt/working-with-event-notifications.html#REDSHIFT-EVENT-2000 ","Event Message":"Amazon Redshift cluster \'qa-redshift-cluster\' has been created at 2021-04-08 20:12 UTC and is ready for use."}

Answer 2

您必须使用两个反斜杠来转义 python 中的双引号，例如\\" 。

此事件将起作用：

st = """
{"Records":[{
         "EventSource":"aws:sns",
         "EventVersion":"1.0",
         "EventSubscriptionArn":"arn:aws:sns:us-east-2:427128480143:terraform-redshift-sns-topic:cbdfec04-7502-4509-9954-435e2ddc5e3c",
         "Sns":{
            "Type":"Notification",
            "MessageId":"fecb7b39-a861-5450-9179-23d0ce68f268",
            "TopicArn":"arn:aws:sns:us-east-2:427128480243:terraform-redshift-sns-topic",
            "Subject":"AmazonRedshift INFO - Cluster Created",
            "Message":"{\\"Event Source\\":\\"cluster\\",\\"Resource\\":\\"qa-redshift-cluster\\",\\"Event Time\\":\\"2021-04-08 20:12:57.466\\",\\"Identifier Link\\":\\"https://console.aws.amazon.com/redshift/home?region=us-east-2#cluster-details:cluster=qa-redshift-cluster \\",\\"Severity\\":\\"INFO\\",\\"Category\\":[\\"Management\\"],\\"About this Event\\":\\"http://docs.aws.amazon.com/redshift/latest/mgmt/working-with-event-notifications.html#REDSHIFT-EVENT-2000 \\",\\"Event Message\\":\\"Amazon Redshift cluster 'qa-redshift-cluster' has been created at 2021-04-08 20:12 UTC and is ready for use.\\"}",
            "Timestamp":"2021-04-08T20:12:57.905Z",
            "SignatureVersion":"1",
            "Signature":"jS2AK8hf/rebeXMsfFw0DJx+788w+RiDTXyAbLNZzYdE5Mlhi6GRRIns8VaAJZc5otXkkhGshvgvuE0JsUiOhXBccGEJY6Z+lhx6cLSQoEdQB0DRfwltWKOfpQ88LZXJuKCxYcsPL3y5veBdjJqwjdBZtcVYV9BYRhQvT6q/0MpDcJeOYzMkdpR2ULX5B7GasZ3AV0WbKxIjjzFSd3GNud2m85obRrB//NHQwqN6ydvg7PaN/sXuyJjmguRok27O6YNkIqzKjC4JxDbTl4BwyIbck59edbHC5kxmfpoc/RqjF/kUGaqnf0HYOUuMfDT85+9wYVz8vFFER1v3NnKRLA==",
            "SigningCertUrl":"https://sns.us-east-2.amazonaws.com/SimpleNotificationService-010a507c1833636cd94bdd98bd93083a.pem",
            "UnsubscribeUrl":"https://sns.us-east-2.amazonaws.com/?Action=Unsubscribe&SubscriptionArn=arn:aws:sns:us-east-2:427128480243:terraform-redshift-sns-topic:cbdfec04-7502-4509-9954-435e7ddc5e3c",
            "MessageAttributes":{

            }
         }
      }
   ]
}
"""