lambda_incoming_email.py

#!/usr/bin/env python
# vim:fileencoding=utf-8

""" [NAME] script or package easy description

[DESCRIPTION] script or package description
"""
import os, sys, io
import json
import boto3
import email
from pyline_notify import PyLINENotify
from decimal import Decimal
from email.header import decode_header
from email.utils import parsedate_to_datetime

__author__  = 'holly'
__version__ = '1.0'

DESCRIPTION = 'this is description'
MESSAGE = """
{Subject}
---
AWS SES to S3 notification

eventTime:   {eventTime}
eventSource: {eventSource}
eventName:   {eventName}
arn:         {arn}
S3URI:       {S3URI}
---
From:    {From}
To:      {To}

{Content}
"""

def get_header(msg, key):

    header = ""
    if msg[key]:
        for tup in decode_header(msg[key]):
            if type(tup[0]) is bytes:
                charset = tup[1]
                if charset:
                    header += tup[0].decode(tup[1])
                else:
                    header += tup[0].decode()
            elif type(tup[0]) is str:
                header += tup[0]

    return header


def get_content(msg):

    charset = msg.get_content_charset()
    payload = msg.get_payload(decode=True)
    try:
        if payload:
            if charset:
                return payload.decode(charset)
            else:
                return payload.decode()
        else:
            return ""
    except:
        # fallback
        return payload


def lambda_handler(event, context):

    line = PyLINENotify(os.environ["LINE_TOKEN"])
    s3 = boto3.client("s3")
    for record in event["Records"]:

        data  = {}
        data["eventTime"]   = record["eventTime"]
        data["eventName"]   = record["eventName"]
        data["eventSource"] = record["eventSource"]
        bucket     = record["s3"]["bucket"]["name"]
        key        = record["s3"]["object"]["key"]

        data["S3URI"]     = "s3://{0}/{1}".format(bucket, key)
        data["arn"]       = record["s3"]["bucket"]["arn"]

        subject = ""
        body    = s3.get_object(Bucket=bucket, Key=key)["Body"].read()
        msg     = email.message_from_bytes(body)

        spam_flag  = False
        virus_flag = False
        for key in [ "X-SES-Spam-Verdict", "X-SES-Virus-Verdict", "From", "Subject", "To" ]:

            if key == "X-SES-Spam-Verdict" and msg[key] != "PASS":
                spam_flag = True
                break
            if key == "X-SES-Virus-Verdict" and msg[key] != "PASS":
                virus_flag = True
                break
            if key == "Subject" or key == "From" or key == "To":
                data[key] = get_header(msg, key)

        if spam_flag:
            print("{0} is spam mail. skip.".format(data["S3URI"]))
            continue
        if virus_flag:
            print("{0} is virus mail. skip.".format(data["S3URI"]))
            continue

        content = get_content(msg)
        if isinstance(content, bytes):
            content = content.decode(msg.get_content_charset(), errors='replace')
        data["Content"] = content


        message = MESSAGE.format(**data)
        kwargs = {}
        if os.environ.get("LINE_STICKER_PACKAGE_ID"):
            kwargs["stickerPackageId"] = os.environ.get("LINE_STICKER_PACKAGE_ID")
        if os.environ.get("LINE_STICKER_ID"):
            kwargs["stickerId"] = os.environ.get("LINE_STICKER_ID")
        res = line.notify(message, **kwargs)
        print("=========================")
        print(res.status_line())
        print("=========================")

    return {
        'statusCode': 200,
        'body': 'done'
    }

if __name__ == '__main__':
    if not os.path.isfile("event.json") : 
        print("event.json is not exists. skip")
        sys.exit(0)
    event = json.load(open("event.json", "r"))
    context = {}
    res = lambda_handler(event, context)
    print(res)