cloudwatchのサブスクリプションにlambdaを登録してエラーをslackに通知するスクリプト

cloudwatch_err_slack.py

import os
import gzip
import json
import base64
from urllib.request import Request, urlopen
from urllib.error import URLError, HTTPError

SLACK_CHANNEL = os.environ['SLACK_CHANNEL']
SLACK_WEBHOOK = os.environ['SLACK_WEBHOOK']


def lambda_handler(event, context):
    print("Event: " + str(event))
    cw_data = event['awslogs']['data']

    compressed_payload = base64.b64decode(cw_data)
    uncompressed_payload = gzip.decompress(compressed_payload)
    payload = json.loads(uncompressed_payload)
    print("payload: " + str(payload))

    log_events = payload['logEvents']
    print("log_events: " + str(log_events))
    for log_event in log_events:
        send_message(log_event)

    return {
        'statusCode': 200,
        'body': json.dumps('finish!')
    }


def send_message(log_event):
    slack_message = {
        'channel': 'your-slack-chanell',
        'icon_emoji': ":error-dayo:",
        'username': 'your-username',
        'attachments': [
            {
                'color': '#ff4400',
                'title': 'error messenger',
                'fields': [
                    {
                        'title': 'message',
                        'value': log_event['message'],
                        'short': True,
                    }
                ]
            }
        ]
    }

    req = Request(SLACK_WEBHOOK, json.dumps(slack_message).encode("utf-8"))
    try:
        response = urlopen(req)
        response.read()
        print("Message posted to ", slack_message['channel'])
    except HTTPError as e:
        print("error: Request failed: ", e.code, e.reason)
    except URLError as e:
        print("error: Server connection failed: ", e.reason)