New configuration values for limiting CRUD results, choosing number of results and default pagelenght

[mariovillani]

Showing all the results in CRUD controllers may be a slow operation (client-side, due to the rendering of datatables and server-side for the query itself).
Actually, it is possible to set the default number of rows:

$this->crud->setDefaultPageLength(10); // number of rows shown in table view by default (client-side)

$this->crud->setPageLengthMenu([100, 200, 300]); // values to put in the number of results selector (client-side)

Then, it is requested to use limit to prevent querying for too much data server side:

$this->crud->limit(50); //limit number of results (server-side)

Those instructions need to be added in each CRUD controller. I think would be better to add some global configuration vars for CRUD package, setting:

• pageLenght entries
• default page length
• limit number of results

for ALL crud entities.

[karandatwani92]

Hey @mariovillani

Yes, you can globally set the config here config/backpack/crud.php

'defaultPageLength' => 10,
'pageLengthMenu' => [[10, 25, 50, 100, -1], [10, 25, 50, 100, 'backpack::crud.all']],

[mariovillani]

@karandatwani92 Correct file is config/backpack/operations/list.php.

I've changed it to:

    // How many items should be shown by default by the Datatable?
    // This value can be overwritten on a specific CRUD by calling
    // $this->crud->setDefaultPageLength(50);
    'defaultPageLength' => 10,

    // A 1D array of options which will be used for both the displayed option and the value, or
    // A 2D array in which the first array is used to define the value options and the second array the displayed options
    // If a 2D array is used, strings in the right hand array will be automatically run through trans()
    'pageLengthMenu' => [[10, 25, 50, 100], [10, 25, 50, 100]],

to fit my needs. As i've said, there is no server-side check made. I may alter the HTML of the select and choose -1 to show all results. A server side check must be done. @pxpm can you check too?

[pxpm]

@mariovillani I was already tracking this issue and was expecting to reply to you shortly, I am going to be busy the next hour or so Laravel-Backpack/CRUD#5503

I will finish it and merge it today. You are totally right about the server side and that can have a performance impact for all the users.

Thanks for the heads up 🙏

[pxpm]

@mariovillani just released https://github.com/Laravel-Backpack/CRUD/releases/tag/6.7.9 where you shouldn't be able to use any value outside the pageLengthMenu you defined.

Ler me know if that solves your issue.

Cheers

[mariovillani]

@pxpm perfect! when trying to input a page length different from the fixed one in the config files, server is returning error 400 "Unknown page length". Thank you!