How to use Boto3 to update the scheduler of a crawler in AWS Glue Data Catalog

In this article, we will see how to update the scheduler of a crawler present in an AWS account.


Problem Statement: Use boto3 library in Python to update the scheduler of a crawler.

Approach/Algorithm to solve this problem

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

  • Step 2: crawler_name and scheduler are the required parameters in this function.

  • The format of scheduler should be as cron(cron_expression). Cron_Expression can be written as (15 12 * * ? *), i.e., the crawler will run every day at 12:15UTC.

  • 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: Now use the update_crawler_schedule function and pass the parameter crawler_name as CrawlerName and scheduler as Schedule.

  • Step 6: It returns the response metadata and updates the schedule state of the crawler.

  • Step 7: Handle the generic exception if something went wrong while updating the scheduler of a crawler.

Example Code

The following code updates the scheduler of a crawler −

import boto3
from botocore.exceptions import ClientError

def update_scheduler_of_a_crawler(crawler_name, scheduler)
   session = boto3.session.Session()
   glue_client = session.client('glue')
      response = glue_client.update_crawler_schedule(CrawlerName=crawler_name,       Schedule=scheduler)
      return response
   except ClientError as e:
      raise Exception("boto3 client error in update_scheduler_of_a_crawler: " + e.__str__())
   except Exception as e:
      raise Exception("Unexpected error in update_scheduler_of_a_crawler: " + e.__str__())
print(update_scheduler_of_a_crawler("Data Dimension","cron(15 12 * * ? *)"))


{'ResponseMetadata': {'RequestId': '73e50130-*****************8e', 'HTTPStatusCode': 200, 'HTTPHeaders': {'date': 'Sun, 28 Mar 2021 07:26:55 GMT', 'content-type': 'application/x-amz-json-1.1', 'content-length': '2', 'connection': 'keep-alive', 'x-amzn-requestid': '73e50130-***************8e'}, 'RetryAttempts': 0}}