Python AWS Lambda 事件 JSON

Question

I am trying to parse event data of AWS Lambda, I have connected it to SQS and I am sending the JSON format using SQS.

This is my AWS Lambda Function

import json

def lambda_handler(event, context):
    # print(event)
    # print(event['Records'][0])
    x = event['Records'][0]['body']
    print(x)
    print(type(x))

Following is the event data

{
   "Records":[
      {
         "messageId":"916f5e95-b2f6-4148-9c62-2ac8e764f06c",
         "receiptHandle":"AQEBmLuoGWtLtFFgvyCFdSPMJh2HKgHOIPWNUq22EOwCzGT8iILZm97CE6j4J6oR71ZpDr3sgxQcJyVZ+dmmvGl+fFftT9GCJqZYrjMGsR2Q6WsMd8ciI8bTtDXyvsk8ektd7UGfh4gxIZoFp7WUKVRcMEeBkubKd8T4/Io81D0l/AK7MxcEfCj40vWEsex1kkGmMRlBtdSeGyy7fJgUq5CFAYWciiWtbSit8S0Y38xZPmsIFhoxP0egQRoJcW4aUgMi469Gj5+khizetybtgC8vux5NCg/IejxcCueXkQ7LKVF8kfRdqRSUYB6DsOrGgfmZpK4wpXIarByNz0R2p7J88meYpj2IVULv/emXsSYaKG4rXnpbH4J9ijbLWckYLAd7wPDzCYri1ZSTgAz0kchsEw==",
         "body":"{\n\"name\": \"aniket\",\n\"tag\": \"hello\"\n}",
         "attributes":{
            "ApproximateReceiveCount":"1",
            "SentTimestamp":"1602046897707",
            "SenderId":"AIDAR3BXDV4FCWXL56NUU",
            "ApproximateFirstReceiveTimestamp":"1602046897712"
         },
         "messageAttributes":{
            
         },
         "md5OfBody":"98da683a47692b39c1d43bd4fa21ed89",
         "eventSource":"aws:sqs",
         "eventSourceARN":"arn:aws:sqs:ap-south-1:126817120010:documentation",
         "awsRegion":"ap-south-1"
      }
   ]
}
    

I am trying to access the body of the data.

this is what I am getting

"{\n\"name\": \"aniket\",\n\"tag\": \"hello\"\n}"

And it's type is string.

What do I need to do convert it into a proper JSON format?

I also tried the following:

import json

def lambda_handler(event, context):
    data = json.dumps(event['Records'][0]['body'])
    print(data)

This is the output

"{\n\"name\": \"aniket\",\n\"tag\": \"hello\"\n}"

But this time the type is JSON.

The expected format is

{
"name": "aniket",
"tag": "hello"
}

Answer 1

You have to use json.loads not json.dumps .

Try this:

import json

event = {
   "Records":[
      {
         "messageId":"916f5e95-b2f6-4148-9c62-2ac8e764f06c",
         "receiptHandle":"AQEBmLuoGWtLtFFgvyCFdSPMJh2HKgHOIPWNUq22EOwCzGT8iILZm97CE6j4J6oR71ZpDr3sgxQcJyVZ+dmmvGl+fFftT9GCJqZYrjMGsR2Q6WsMd8ciI8bTtDXyvsk8ektd7UGfh4gxIZoFp7WUKVRcMEeBkubKd8T4/Io81D0l/AK7MxcEfCj40vWEsex1kkGmMRlBtdSeGyy7fJgUq5CFAYWciiWtbSit8S0Y38xZPmsIFhoxP0egQRoJcW4aUgMi469Gj5+khizetybtgC8vux5NCg/IejxcCueXkQ7LKVF8kfRdqRSUYB6DsOrGgfmZpK4wpXIarByNz0R2p7J88meYpj2IVULv/emXsSYaKG4rXnpbH4J9ijbLWckYLAd7wPDzCYri1ZSTgAz0kchsEw==",
         "body":"{\n\"name\": \"aniket\",\n\"tag\": \"hello\"\n}",
         "attributes":{
            "ApproximateReceiveCount":"1",
            "SentTimestamp":"1602046897707",
            "SenderId":"AIDAR3BXDV4FCWXL56NUU",
            "ApproximateFirstReceiveTimestamp":"1602046897712"
         },
         "messageAttributes":{

         },
         "md5OfBody":"98da683a47692b39c1d43bd4fa21ed89",
         "eventSource":"aws:sqs",
         "eventSourceARN":"arn:aws:sqs:ap-south-1:126817120010:documentation",
         "awsRegion":"ap-south-1"
      }
   ]
}

parsed = json.loads(event['Records'][0]['body'])
print(json.dumps(parsed, indent=4, sort_keys=True))

Output:

{
    "name": "aniket",
    "tag": "hello"
}

Answer 2

Try using json.loads(string) to deserialize the json.

Also, I don't believe you need to specify the index [0] since 'body' is an object and not an array.