Fix #2365 - Campaign Emails are queued, but it stops sending after about 78 or 79 recipients

[sanchezfauste]

Replication of #2569

Description

References issue #2365

Activate SMTP Keep Alive for Campaign Mass Emailer.

Motivation and Context

To reduce the CPU load on the SMTP Server, and reduce the chance of errors and throttling of the Campaign Mass Emailer by improving performance.

How To Test This

Create a Campaign in a version of SuiteCRM without this update.
Create a Campaign and send it using the Scheduler.
Calculate the time for each batch by viewing the log and search for the timestamps and subtract start time from end time for each batch of X emails (default is 500 emails).
Then run a Campaign on a version of SuiteCRM with this patch.
Send it using the Scheduler.
Calculate the time for each each batch by viewing the log, and search for the timestamps and subtract start time from end time for each batch of X emails (default is 500 emails).
The time to send the batch of campaign emails should be significantly faster.

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)

Final checklist

• My code follows the code style of this project found here.
• My change requires a change to the documentation.
• I have read the How to Contribute guidelines.

[amariussi]

Instead of hard coding it it would be better to use a config variable to allow users to decide whether to use it or not.
This method is indeed more efficient but increases the chances of being reported as spammers!
I would also add one extra variable to close the session after a certain number of iterations. (a little more complex, but a much better approach!)

[sanchezfauste]

I can add a checkbox (disabled by default) to choose if SMTP connection has to keep alive or not in Campaign Email Settings.

It would be interesting to get feedback from more users.

[Mac-Rae]

Please rebase this pull request to the hotfix-7.10.x branch as version 7.8.x of SuiteCRM has reached its end of life and therefore will no longer be receiving updates.

For more information about 7.8.x end of life please visit our blog post

[sanchezfauste]

Please rebase this pull request to the hotfix-7.10.x branch as version 7.8.x of SuiteCRM has reached its end of life and therefore will no longer be receiving updates.

For more information about 7.8.x end of life please visit our blog post

Done.

[Mac-Rae]

Assessed 👍

[codecov-commenter]

Codecov Report

Merging #5883 into hotfix-7.10.x will decrease coverage by 0.00%.
The diff coverage is 0.00%.

@@                Coverage Diff                @@
##           hotfix-7.10.x    #5883      +/-   ##
=================================================
- Coverage          10.70%   10.70%   -0.01%     
=================================================
  Files               3230     3230              
  Lines             241058   241060       +2     
=================================================
  Hits               25798    25798              
- Misses            215260   215262       +2     

[SuiteBot]

All committers have signed the CLA.