TypeError: a bytes-like object is required, not 'str' with serverless and Python3

Question

我有一个 aws-lambda 函数，每当 CSV 文件上传到 s3 存储桶时就会触发该函数。我在 Python 3.6 中使用无服务器框架，问题是我收到此错误消息

a bytes-like object is required, not 'str': TypeError

Traceback (most recent call last):

File "/var/task/handler.py", line 33, in csvfile

fichier = obj['Body'].read().split('\n')

TypeError: a bytes-like object is required, not 'str'

我在网上做了一些研究，问题是我没有使用打开方法导致文件被 s3 事件读取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 serverless.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

Answer 1

问题在于

fichier = obj['Body'].read()

returns 一个 bytes 对象，不是字符串。这是因为编码可能需要多个字符。现在你在 bytes 对象上使用 split，但你不能使用字符串拆分它，你需要使用另一个 bytes 对象进行拆分。具体来说

fichier = obj['Body'].read().split(b'\n')

应该可以解决您的错误，但根据您的期望，在拆分之前解码可能更合适？

fichier = obj['Body'].read().decode("utf-8").split('\n')

TypeError: a bytes-like object is required, not 'str' with serverless and Python3

TypeError: a bytes-like object is required, not 'str' with serverless and Python3

python

csv

amazon-s3

amazon-web-services

serverless-framework