TypeError:需要类似字节的对象,而不是serverless和Python3的“str”

我有一个aws lambda函数,每当CSV文件上传到s3 bucket时就会触发。我在Python 3.6中使用无服务器框架,问题是我收到了这个错误消息

需要类似字节的对象,而不是“str”:TypeError

回溯(最近一次呼叫最后一次):

csvfile中第33行的文件“/var/task/handler.py”

fichier=obj['Body']。读取()。拆分(“\n”)

TypeError:需要类似字节的对象,而不是“str”

我在网上做了一些研究 here 问题是,我没有使用open方法,因为文件是由s3事件读取的,所以不知道如何修复它

这是我的代码:

import logging
import boto3
from nvd3 import pieChart
import sys
import csv


xdata = []
ydata = []
xdata1 = []
ydata1 = []


logger = logging.getLogger()
logger.setLevel(logging.INFO)

def csvfile(event, context):

    s3 = boto3.client('s3')    
    # retrieve bucket name and file_key from the S3 event
    bucket_name = event['Records'][0]['s3']['bucket']['name']
    file_key = event['Records'][0]['s3']['object']['key']
    logger.info('Reading {} from {}'.format(file_key, bucket_name))
    # get the object
    obj = s3.get_object(Bucket=bucket_name, Key=file_key)
    # get lines inside the csv
    fichier = obj['Body'].read().split('\n')
    #print lines
     for ligne in fichier:
        if len(ligne) > 1:
            logger.info(ligne.decode())
            liste = ligne.split(',')
            print(liste)
            if liste[2] == 'ByCateg':
                xdata.append(liste[4]) 
                ydata.append(liste[1]) 
            elif liste[2] == 'ByTypes':
                xdata1.append(liste[4]) 
                ydata1.append(liste[1]) 

         print ' '.join(xdata) 

print('Function execution Completed')

这是我的无服务器。yml代码:

service: aws-python # NOTE: update this with your service name

provider:
  name: aws
  runtime: python3.6
  stage: dev
  region: us-east-1
  iamRoleStatements:
        - Effect: "Allow"
          Action:
              - s3:*
              - "ses:SendEmail"
              - "ses:SendRawEmail"
              - "s3:PutBucketNotification"
          Resource: "*"

    functions:
  csvfile:
    handler: handler.csvfile
    description: send mail whenever a csv file is uploaded on S3 
    events:
      - s3:
          bucket: car2
          event: s3:ObjectCreated:*
          rules:
            - suffix: .csv