Put json file to S3 from Lambda

put_s3_from_lambda.py

import json
import os
import boto3
import botocore


def handler(event, context):
    bucket = os.environ.get('BUCKET')
    key = os.environ.get('KEY')

    s3_resource = boto3.resource('s3')
    obj = s3_resource.Object(bucket, key)
    try:
        current_json = json.loads(obj.get()['Body'].read().decode('utf-8'))
    except botocore.exceptions.ClientError:
        # file does not exist
        updated_json = {'sample': 1}
    else:
        # file exist
        if not isinstance(current_json['key'], int):
            current_json['key'] = 0
        current_json['key'] = current_json['key'] + 1
        updated_json = current_json
    r = obj.put(Body=json.dumps(updated_json))
    result = {'Body': obj.get()['Body'].read().decode('utf-8')}
    return result

いいですね！

これもできる！

from botocore.exceptions import ClientError

try:
    response = s3.get_object(Bucket=bucket, Key=key)
except ClientError as ex:
    if ex.response['Error']['Code'] == 'NoSuchKey':
        logger.info('No object found - returning empty')
        return dict()
    else:
        raise

https://stackoverflow.com/questions/42975609/how-to-capture-botocores-nosuchkey-exception