[jira] [Commented] (AIRFLOW-2763) No precheck mechanism in place during worker initialisation for the connection to metadata database

["ASF GitHub Bot (JIRA)" <ji...@apache.org>]

    [ https://issues.apache.org/jira/browse/AIRFLOW-2763?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16575506#comment-16575506 ] 

ASF GitHub Bot commented on AIRFLOW-2763:
-----------------------------------------

amohan34 opened a new pull request #3726: [AIRFLOW-2763] Add check to validate worker connectivity to metadata …
URL: https://github.com/apache/incubator-airflow/pull/3726
 
 
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> No precheck mechanism in place during worker initialisation for the connection to metadata database
> ---------------------------------------------------------------------------------------------------
>
>                 Key: AIRFLOW-2763
>                 URL: https://issues.apache.org/jira/browse/AIRFLOW-2763
>             Project: Apache Airflow
>          Issue Type: Improvement
>          Components: db, worker
>            Reporter: Aishwarya Mohan
>            Assignee: Aishwarya Mohan
>            Priority: Major
>
> Currently when airflow worker is started, no initialization check is in place to see if the connection to metadata database is healthy or not. The worker threads remain alive(after throwing exceptions - OperationalError) leading to a misconception that the worker is up and running the tasks allocated. 
> In the case of worker interaction with the broker, a reconnection mechanism exists the exits the worker  due to timeout operational error if it failed to establish connection within the configured number of attempts(connection_max_retries).
> An exit/shutdown mechanism needs to be included during worker initialization incase the connection to  metadata DB is not established. This will assure the airflow users that the connection to database is in place before they proceed with task scheduling.



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