Eloquent - Group By Month, Year and Paginate - php

Question

I am trying to list entries in a table by Month, Year:
May, 2015
Item 1
Item 2
Item 3
June, 2015
Item 1
etc..
I have achieved this with the following code but I would also like to paginate the results. I have tried many different things but none of them seem to work, I am using Laravel 5.
$events = App\Events->orderBy('start', 'asc')->get()->groupBy(function($date) {
return $date->start->format('F, Y');
});
Here is the output for the above query:
{
"April, 2015": [
{
"id": "10",
"event_type_id": "1",
"user_id": "1",
"title": "Testing",
"slug": "testing",
"start": "2015-04-23 17:00:00",
"end": "2015-04-23 17:40:00",
"description": "<h1>MEETING!</h1><p>Let's try this in HTML!<br></p>",
"created_at": "2015-04-19 14:18:33",
"updated_at": "2015-04-21 22:07:41",
"type": {
"id": "1",
"name": "General",
"slug": "general",
"created_at": "2015-04-18 11:24:00",
"updated_at": "2015-04-18 11:24:04"
}
}
],
"May, 2015": [
{
"id": "12",
"event_type_id": "1",
"user_id": "1",
"title": "Test Event",
"slug": "test-event",
"start": "2015-05-15 18:00:00",
"end": null,
"description": "<p>This is a test event with just a start time</p>",
"created_at": "2015-04-21 14:59:56",
"updated_at": "2015-05-02 18:37:53",
"type": {
"id": "1",
"name": "General",
"slug": "general",
"created_at": "2015-04-18 11:24:00",
"updated_at": "2015-04-18 11:24:04"
}
},
{
"id": "9",
"event_type_id": "1",
"user_id": "1",
"title": "Monthly Meeting",
"slug": "monthly-meeting",
"start": "2015-05-23 14:00:00",
"end": "2015-04-16 20:00:00",
"description": "<p>It's a long monthly meeting!</p>",
"created_at": "2015-04-19 13:13:45",
"updated_at": "2015-05-03 08:45:56",
"type": {
"id": "1",
"name": "General",
"slug": "general",
"created_at": "2015-04-18 11:24:00",
"updated_at": "2015-04-18 11:24:04"
}
}
],
"June, 2015": [
{
"id": "11",
"event_type_id": "1",
"user_id": "1",
"title": "Another Meeting Saved",
"slug": "another-meeting-saved",
"start": "2015-06-19 18:00:00",
"end": null,
"description": "<p>It's another meeting afterall</p>",
"created_at": "2015-04-20 15:03:30",
"updated_at": "2015-05-03 08:46:19",
"type": {
"id": "1",
"name": "General",
"slug": "general",
"created_at": "2015-04-18 11:24:00",
"updated_at": "2015-04-18 11:24:04"
}
}
]
}
With LengthAwarePaginator -
$paginator = new LengthAwarePaginator($events, count($events), 1);
return $paginator;
This returns the paginator but the data is the same - meaning the same result set as without the paginator, when I'd expect only one record to be returned per page:
[{
"total": 3,
"per_page": 1,
"current_page": 1,
"last_page": 3,
"next_page_url": "/?page=2",
"prev_page_url": null,
"from": 1,
"to": 3,
"data": {
"data" : ".. same as above"
}
}]

Answer 1

With aggregates you need to implement your own custom paginator, as stated by docs:
Note: Currently, pagination operations that use a groupBy statement
cannot be executed efficiently by Laravel. If you need to use a
groupBy with a paginated result set, it is recommended that you query
the database and create a paginator manually.
See this posts to manually implement pagination:
Laravel 5 - Manual pagination
Manually Creating a Paginator (Laravel 5)

Answer 2

Many people have pointed me to a widely mentioned paragraph in the Laravel documentation,
Note: Currently, pagination operations that use a groupBy statement
cannot be executed efficiently by Laravel. If you need to use a
groupBy with a paginated result set, it is recommended that you query
the database and create a paginator manually.
Not terribly helpful, since I cannot find any example in the documentation as to exactly how to create a manual paginator using the results of an Eloquent query. So, here is what I was able to come up with. Note that you must use ->take() and ->offset() in the query, otherwise you will end up with the same results on every page (this is where I was getting stuck).
<?php
// routes.php
use Illuminate\Pagination\LengthAwarePaginator as Paginator;
get('test', function(Request $request) {
$page = $request->has('page') ? $request->input('page') : 1; // Use ?page=x if given, otherwise start at 1
$numPerPage = 2; // Number of results per page
$eventType = EventType::find(1); // Not relevant to pagination
$count = $eventType->memberEvents()->count(); // Get the total number of entries you'll be paging through
// Get the actual items
$events = $eventType->memberEvents()->orderBy('start', 'asc')
->take($numPerPage)->offset(($page-1)*$numPerPage)->get()->groupBy(function($date) {
return $date->start->format('F, Y');
});
// Create the paginator with Illuminate\Pagination\LengthAwarePaginator as Paginator
// Pass in the variables supplied above, including the path for pagination links
$paginator = new Paginator($events, $count, $numPerPage, $page, ['path' => $request->url(), 'query' => $request->query()]);
return $paginator;
});

Answer 3

If you want to add groupBy to your data the you should use LengthAwarePaginator object as updated in laravel 5
Try this,
use Illuminate\Pagination\LengthAwarePaginator as Paginator;
$page = ($request->input('page') != null) ? $request->input('page') : 1;
$perPage = 1;
$sliced = array_slice($data, 0, 5); //you can these values as per your requirement
$paginator = new Paginator($sliced, count($data), $perPage, $page,['path' => url()->current(),'query' => $request->query()]);
return $paginator;
$data is your data object and fifth parameters are for next and prev urls
Refer this for more information about paginator,
https://laravel.com/api/5.5/Illuminate/Database/Eloquent/Builder.html#method_paginate

Answer 4

As stated in the Laravel docs...Note: Currently, pagination operations that use a groupBy statement cannot be executed efficiently by Laravel. If you need to use a groupBy with a paginated result set, it is recommended that you query the database and create a paginator manually. Docs