DynamoDB data to JSON file

dynamodb_dump.py

# Dump DynamoDB data to JSON file
# s3://[bucket]/offine-cms-[table-name].json

# Refs: https://boto3.amazonaws.com/v1/documentation/api/latest/guide/quickstart.html

import decimal
import json
import boto3
from boto3.dynamodb.conditions import Key, Key, Attr


class DecimalEncoder(json.JSONEncoder):
   def default(self, obj):
       if isinstance(obj, decimal.Decimal):
           return float(obj)
       return super(DecimalEncoder, self).default(obj)


def aws_s3_sync(region_s, bucket_s, file_name_s, data_s):
    from botocore.client import Config
    s3_client = boto3.client(service_name='s3', region_name=region_s,
                             config=Config(signature_version='s3'))
    s3_client.put_object(Body=data_s, Bucket=bucket_s, Key=file_name_s)


def dump(region_s, table_name_s, bucket_s):
	session = boto3.Session(region_name=region_s)
	dynamodb = session.resource('dynamodb')
	table = dynamodb.Table(table_name_s)
	response = table.scan(AttributesToGet=['content_id', 'content', 'updated_at'])
	data = response['Items']
	while 'LastEvaluatedKey' in response:
	    response = table.scan(ExclusiveStartKey=response['LastEvaluatedKey'])
	    data.extend(response['Items'])
	aws_s3_sync(region_s, bucket_s, 'offine-cms-{0}.json'.format(table_name_s), json.dumps(data, sort_keys=True, cls=DecimalEncoder))


dump('us-east-1', 'table-name', 'bucket-name')