Reading files caused by s3 event

Question

Here is what I want to do:

• The user loads the csv file into the AWS S3 bucket.
• After loading the file, the S3 bucket calls the lambda function I created.
• My lambda function reads the contents of the csv file, then sends an email with the contents of the file and information

Local environment

Serviceless version 1.22.0

Python 2.7

Here is my serverless.yml file

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

provider:
  name: aws
  runtime: python2.7
  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: mine2
          event: s3:ObjectCreated:*
          rules:
            - suffix: .csv

and here is my lambda function:

import json
import boto3
import botocore
import logging
import sys
import traceback
import csv

from botocore.exceptions import ClientError
from pprint import pprint
from time import strftime, gmtime
from json import dumps, loads, JSONEncoder, JSONDecoder


#setup simple logging for INFO
logger = logging.getLogger()
logger.setLevel(logging.INFO)

from botocore.exceptions import ClientError

def csvfile(event, context):
    """Send email whenever a csvfile is uploaded to S3 """
    body = {}
    emailcontent = ''
    status_code = 200
    #set email information
    email_from = '****@*****.com'
    email_to = '****@****.com'
    email_subject = 'new file is uploaded'
    try:
        s3 = boto3.resource(u's3')
        s3 = boto3.client('s3')
        for record in event['Records']:
            filename = record['s3']['object']['key']
            filesize = record['s3']['object']['size']
            source = record['requestParameters']['sourceIPAddress']
            eventTime = record['eventTime']
        # get a handle on the bucket that holds your file
        bucket = s3.Bucket(u'mine2')
        # get a handle on the object you want (i.e. your file)
        obj = bucket.Object(key= event[u'Records'][0][u's3'][u'object'][u'key'])
        # get the object
        response = obj.get()
        # read the contents of the file and split it into a list of lines
        lines = response[u'Body'].read().split()
        # now iterate over those lines
        for row in csv.DictReader(lines):    
            print(row)
            emailcontent = emailcontent + '\n' + row 
    except Exception as e:
        print(traceback.format_exc())
        status_code = 500
        body["message"] = json.dumps(e)

    email_body = "File Name: " + filename + "\n" + "File Size: " + str(filesize) + "\n" +  "Upload Time: " + eventTime + "\n" + "User Details: " + source + "\n" + "content of the csv file :" + emailcontent
    ses = boto3.client('ses')
    ses.send_email(Source = email_from,
        Destination = {'ToAddresses': [email_to,],}, 
            Message = {'Subject': {'Data': email_subject}, 'Body':{'Text' : {'Data': email_body}}}
            )
    print('Function execution Completed')

I don’t know what I did wrong, because the part when I just get the file information works fine when I add the reading part that the lambda function does not return anything

Answer 1

IAM Cloudwatch. - , Cloudwatch. logger.info(message) print logger.

, .

, ( AWS):

import logging
import boto3

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

s3 = boto3.client('s3')

def lambda_handler(event, context):
    email_content = ''

    # 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
    lines = obj['Body'].read().split(b'\n')
    for r in lines:
       logger.info(r.decode())
       email_content = email_content + '\n' + r.decode()
    logger.info(email_content)