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How to use Boto3 to paginate through all triggers present in AWS Glue

Problem Statement: Use boto3 library in Python to paginate through all triggers from AWS Glue Data Catalog that is created in your account

Approach/Algorithm to solve this problem

  • Step 1: Import boto3 and botocore exceptions to handle exceptions.

  • Step 2: max_items, page_size and starting_token are the optional parameters for this function

    • max_items denote the total number of records to return. If the number of available records > max_items, then a NextToken will be provided in the response to resume pagination.

    • page_size denotes the size of each page.

    • starting_token helps to paginate, and it uses NextToken from a previous response.

  • Step 3: Create an AWS session using boto3 lib. Make sure region_name is mentioned in the default profile. If it is not mentioned, then explicitly pass the region_name while creating the session.

  • Step 4: Create an AWS client for glue.

  • Step 5: Create a paginator object that contains details of all triggers using get_triggers

  • Step 5: Call the paginate function and pass the max_items, page_size and starting_token as PaginationConfig parameter

  • Step 6: It returns the number of records based on max_size and page_size.

  • Step 7: Handle the generic exception if something went wrong while paginating.

Example Code

Use the following code to paginate through all triggers created in user account −

import boto3
from botocore.exceptions import ClientError

def paginate_through_triggers(max_items=None:int,page_size=None:int, starting_token=None:string):
   session = boto3.session.Session()
   glue_client = session.client('glue')
   try:
   paginator = glue_client.get_paginator('get_triggers')
      response = paginator.paginate(PaginationConfig={
         'MaxItems':max_items,
         'PageSize':page_size,
         'StartingToken':starting_token}
       )
   return response
   except ClientError as e:
      raise Exception("boto3 client error in paginate_through_triggers: " + e.__str__())
   except Exception as e:
      raise Exception("Unexpected error in paginate_through_triggers: " + e.__str__())

page_itr = paginate_through_tables("test_db",2,5)
for page in page_itr:
print(page['Triggers']

Output

[{'Name': 'file-passed', 'WorkflowName': 'data-tx', 'Type': 'CONDITIONAL', 'State': 'ACTIVATED', 'Actions': [{'JobName': 'data-event'}], 'Predicate': {'Logical': 'ANY', 'Conditions': [{'LogicalOperator': 'EQUALS', 'JobName': 'data-worker', 'State': 'SUCCEEDED'}]}},
{'Name': 'file-passed-to-acc', 'WorkflowName': 'tick-data', 'Type': 'CONDITIONAL', 'State': 'ACTIVATED', 'Actions': [{'JobName': 'tick-data'}], 'Predicate': {'Logical': 'ANY', 'Conditions': [{'LogicalOperator': 'EQUALS', 'JobName': 'tick-data', 'State': 'SUCCEEDED'}]}}