Grails 7 - MongoDB Lazy Loading Issue in GSP

[low-he-th]

I recently migrated a multi-module application from Grails 6 to Grails 7.0.1 and am facing a MongoDB lazy-loading issue during GSP rendering.

Project structure:
Main Application

• Module 1 (contains MongoDB domain classes such as Test, Test1, etc.)
• Module 2 (uses domain classes from Module 1)

In a GSP page, I have something like:
test1 class is a Foreign Key(FK) in test class

<g:each in="${testList}" var="test">
    <option value="${test.id}">
        ${test?.test1?.name}
    </option>
</g:each>

After migrating to Grails 7, the page throws the following error:
No datastore session found. Call Datastore.connect(..) before calling Datastore.getCurrentSession().
Interestingly, if I access the association in the controller before rendering the GSP, or if I convert the data to DTOs/maps and pass that to the view, the page works correctly.

1. Has datastore session handling during GSP rendering changed in Grails 7 compared to Grails 6?
2. Is there a recommended global solution for this issue instead of manually initializing associations or creating DTOs for every page?
3. Has anyone faced similar issues in multi-module Grails 7 applications using MongoDB references?

[matrei]

Hi, thanks for reporting this issue.

Could you create a project on GitHub that reproduces the issue? Use the latest Grails 7.0.x release: 7.0.11.

[jdaugherty]

@low-he-th I think I spoke to you on Slack about this, but I believe the reason this has occurred is the hibernate plugin was not being included in the Grails 7 project. The OSIV is implemented only in hibernate. Can you please confirm this is fixed once you adjust your dependencies?

[low-he-th]

Hello @jdaugherty,
Thank you for your support. I haven't implemented that solution yet, but once I do, I'll let you know how it goes.
By the way, I tried something in the Domain class like:
static mapping { test1 fetch: "eager" }
where test1 is a foreign key (FK) association in the Test class. Surprisingly, it worked. However, I will definitely try the solution you suggested as well.