DataTable: Paginator After upgrade to 13.0.6 always uses first=0 in .load() method

[AndrewG10i]

DataTable: Paginator After upgrade to 13.0.6 always uses first=0 in .load() method

[melloware]

@AndrewG10i i am pretty sure based on the migration guide for 11.0.0 you should not have been returning count 0 even then based on this migration note: https://primefaces.github.io/primefaces/13_0_0/#/../migrationguide/11_0_0?id=datatable-dataview-datagrid-datalist

[melloware]

@tandraschko @AndrewG10i @jungm I got to the bottom of it and its this fix: #11402

It also came with an integration test so we have conflicting issues both with integration tests proving something is wrong.

[melloware]

See: #11377

It's only for virtual scroll and live scroll. So it should not affect paginator at all. As there is no paging in live scroll or virtual scroll mode?

[github-actions]

Please provide an executable example using the PrimeFaces Test project. This issue will be closed if no activities in 20 days.

[AndrewG10i]

This is the code (DataTable declaration) I have:

<p:dataTable id="usersTable" value="#{dirCntroller.usersLazyDS}" lazy="true" var="rowData" rowIndexVar="rowIndex"
             paginator="true" rows="25" rowsPerPageTemplate="25,50,100" paginatorPosition="top" paginatorAlwaysVisible="true"
             paginatorTemplate="{CurrentPageReport} {JumpToPageDropdown} {FirstPageLink} {PreviousPageLink} {PageLinks} {NextPageLink} {LastPageLink} {RowsPerPageDropdown}"
             reflow="true" emptyMessage="#{labels['general.dataTable.noRecordsFound']}" filterDelay="800" styleClass="usersTable" widgetVar="usersTableWV">

I will try to prepare reproducer. Meanwhile decided to report the issue so in case someone else have it they can confirm as well.

[melloware]

We have tons of integrations tests that test pagination and datatable that all passed so if this is a bug it means there is a gap in the integration tests.

[AndrewG10i]

Okay, so far cannot reproduce this issue, reproducer works fine. Will investigate further what exactly triggers issue in my app and in case issue found in the PF lib - will reopen this ticket again. But for now closing it. Thanks!

[melloware]

Thanks yes please let me know what you find out!

[AndrewG10i]

Okay, after spending several hours on this, I finally found the root cause. ;))
Considered particular project uses PF since version 11.x and it was working fine until v13.0.5 (inclusive). But since v13.0.6 - behavior of paginator in DataTable with LazyDataModel has changed.

So basically the root cause is related to the Issue 8062. As discussed in that issue - we also require to use one single API call for retrieving data from the DB, and result returns two values pair: data subset and count of the whole data set.

As such, LazyDataModel.count() method returns 0 only, and the respective handling is implemented in the LazyDataModel.load() method.
And this causes the issue with pagination.

So once I change LazyDataModel.count() from return 0; to return actual count - it fixes behavior of paginator in v13.0.6 as well.

Could you please reopen this issue and provide your feedback? Also please let me know if you would like me to post a reproducer as well. Thank you!

[melloware]

@Rapster @tandraschko thoughts here?

[tandraschko]

we must support cases like seen here: #8062 (comment)
a reproducer would be great

@melloware can you check what did we change DataTable related in 13.0.6? also if we have similar integration tests?

[melloware]

@tandraschko we have tons of integration tests and the only change was to fix LiveScroll and Virtual Scroll. Regular pagination was not touched.

See: #11377

[github-actions]

Please provide an executable example using the PrimeFaces Test project. This issue will be closed if no activities in 20 days.

[AndrewG10i]

@AndrewG10i i am pretty sure based on the migration guide for 11.0.0 you should not have been returning count 0 even then based on this migration note: https://primefaces.github.io/primefaces/13_0_0/#/../migrationguide/11_0_0?id=datatable-dataview-datagrid-datalist

Thanks for pointing to that note. But seems the project still in compliance with it. :)
Under the item "see DataTable for details how to avoid a separate count-statement against your datasource" it basically shows the implementation as per 8062.

Let me post reproducer shortly...

[tandraschko]

@melloware we dont have a testcase for this - we should just copy DataTable037 and implement rowCount return0

[tandraschko]

see tandraschko@cf3f997

it fails currently

[melloware]

OK good thanks for adding a test case. Let me look and see if I can debug.