Helper Script to create DynamoDB Table

Helper Script to create DynamoDB Table

helper_scripts/create_dynamodb_table.py

@@ -0,0 +1,132 @@
+# -*- coding: utf-8 -*-
+__author__ = 'Mystique'
+"""
+.. module: Create DynamoDB Table for the given Schema
+    :platform: AWS
+    :copyright: (c) 2019 Mystique.,
+.. moduleauthor:: Mystique
+.. contactauthor:: miztiik@github issues
+"""
+import boto3
+import json
+import logging
+
+
+# Initialize Logger
+logger = logging.getLogger()
+logger.setLevel(logging.INFO)
+
+def set_global_vars():
+    """
+    Set the Global Variables
+    If User provides different values, override defaults
+
+    This function returns the AWS account number
+
+    :return: global_vars
+    :rtype: dict
+    """
+    global_vars = {'status': False, 'error_message': ''}
+    try:
+        global_vars['Owner']                = "Miztiik"
+        global_vars['Environment']          = "Test"
+        global_vars['region_name']          = "us-east-1"
+        global_vars['tag_key']              = "Valaxy-HelpDesk-Bot"
+        global_vars['ddb_table_name']       = "valaxy-butler-queries"
+        global_vars['ddb_index_name']       = "valaxy-butler-queries-index"
+        global_vars['status']               = True
+    except Exception as e:
+        logger.error(f"ERROR: {str(e)}")
+    return global_vars
+
+def create_ddb_table(global_vars):
+    """
+    Create Dynamo DB Table
+    Params
+    @table_name: Name of the DDB Table
+    @index_name: Name of the Global Secondary Index
+    Right now, the reads happen against the GSI and Writes happen again the main table.
+    The RCU/WCU provisioning is made with this understanding.
+    """
+    dynamodb = boto3.resource('dynamodb', region_name = global_vars.get('region_name'))
+    response = dynamodb.create_table(TableName = global_vars.get('ddb_table_name'),
+                      KeySchema = [{'AttributeName': 'search_query', 'KeyType': 'HASH'}, #Partition key
+                                  ],
+                      AttributeDefinitions = [{'AttributeType': 'S', 'AttributeName': 'search_query'},
+                                              {'AttributeType': 'N', 'AttributeName': 'search_count'}
+                                             ],
+                      GlobalSecondaryIndexes=[
+                                             {
+                                                 'IndexName':global_vars.get('ddb_index_name'),
+                                                 'KeySchema': [
+                                                     {'AttributeName': 'search_count', 'KeyType': 'HASH'}, #Partition key
+                                                 ],
+                                                 'Projection': { 'ProjectionType': 'ALL' },
+                                                 #'Projection': { 'ProjectionType': 'INCLUDE',
+                                                 #                 'NonKeyAttributes': ['lead_name',]
+                                                 #               },
+                                                 'ProvisionedThroughput': {
+                                                     'ReadCapacityUnits': 3,
+                                                     'WriteCapacityUnits': 1
+                                                 }
+                                             },
+                                            ],
+                      ProvisionedThroughput = {
+                          'ReadCapacityUnits': 2,
+                          'WriteCapacityUnits': 3
+                          }
+                          )
+    return response
+
+
+def get_table_metadata(global_vars):
+    """
+    Get some metadata about chosen table.
+    """
+    dynamodb = boto3.resource('dynamodb', region_name = global_vars['region_name'])
+    table = dynamodb.Table( global_vars['ddb_table_name'] )
+    table.meta.client.get_waiter('table_exists').wait(TableName= global_vars['ddb_table_name'])
+    return {
+        'num_items': table.item_count,
+        'primary_key_name': table.key_schema[0],
+        'status': table.table_status,
+        'bytes_size': table.table_size_bytes,
+        'global_secondary_indices': table.global_secondary_indexes
+    }
+
+
+def lambda_handler(event, context):
+    """
+    Entry point for all processing. Load the global_vars
+
+    :return: A dictionary of tagging status
+    :rtype: json
+    """
+    """
+    Can Override the global variables using Lambda Environment Parameters
+    """
+    global_vars = set_global_vars()
+
+    resp = {'statusCode': 200, "status": False, "error_message" : '' }
+
+    create_db_resp = create_ddb_table( global_vars )
+    logger.info(f"Table status:{create_db_resp.table_status}")
+    resp = get_table_metadata( global_vars )
+    logger.info(f"-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+")
+    logger.info(f"{json.dumps(resp, indent=4)}")
+    logger.info(f"-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+")
+
+    return resp
+
+if __name__ == '__main__':
+    lambda_handler(None, None)
+
+
+
+# References
+## [1] [Choosing the Right DynamoDB Partition Key](https://aws.amazon.com/blogs/database/choosing-the-right-dynamodb-partition-key/)
+## [2] [Global Secondary Indexes](https://docs.aws.amazon.com/amazondynamodb/latest/developerguide/GSI.html)
+## [3] [Take Advantage of Sparse Indexes](https://docs.aws.amazon.com/amazondynamodb/latest/developerguide/bp-indexes-general-sparse-indexes.html#bp-indexes-sparse-examples)
+## [4] [Best Practices for Querying and Scanning Data](https://docs.aws.amazon.com/amazondynamodb/latest/developerguide/bp-query-scan.html)
+## [5] [Querying on Multiple Attributes in Amazon DynamoDB](https://aws.amazon.com/blogs/database/querying-on-multiple-attributes-in-amazon-dynamodb/)
+