Listify

Turn any Eloquent model into a list!

Description

Listify provides the capabilities for sorting and reordering a number of objects in a list. The class that has this specified needs to have a position column defined as an integer on the mapped database table. Listify is an Eloquent port of the highly useful Ruby gem acts_as_list (https://github.com/swanandp/acts_as_list).

• Requirements
• Installation
• Quick Start
• Overview
• Configuration
• Notes
• Future Plans
• Contributing
• Copyright

Requirements

• Listify currently requires php >= 5.5 (Listify is implemented via the use of traits).
• Laravel 5.0 or higher

For use with Laravel 4, please use version 1.0.6.

Installation

Listify is distributed as a composer package, which is how it should be used in your app.

Install the package using Composer. Edit your project's composer.json file to require lookitsatravis/listify.

  "require": {
    "laravel/framework": "~5.0",
    "lookitsatravis/listify": "~1.2"
  }

Once this operation completes, the final step is to add the service provider. Open app/config/app.php, and add a new item to the providers array.

    'Lookitsatravis\Listify\ListifyServiceProvider'

Optionally, you can define an alias to the Listify trait. Open app/config/app.php, and add a new item to the aliases array.

    'Listify' => 'Lookitsatravis\Listify\Listify'

Quickstart

First things first, you'll need to add a column to store the position. From the command line, use the migration generator:

php artisan listify:attach {table_name} {position_column_name}
php artisan migrate

{table_name} is a required argument. {position_column_name} is optional and the default value is "position".

Then, in your model:

class User extends Eloquent
{
    use \Lookitsatravis\Listify\Listify;

    public function __construct(array $attributes = array(), $exists = false) {

        parent::__construct($attributes, $exists);

        $this->initListify();
    }
}

Make sure that the initListify() method is called after parent::__construct() of your model.

That's all it takes to get access to the Listify hotness.

Overview

Instance Methods Added To Eloquent Models

You'll have a number of methods added to each instance of the Eloquent model to which Listify is added.

In Listify, "higher" means further up the list (a lower position), and "lower" means further down the list (a higher position). That can be confusing, so it might make sense to add tests that validate that you're using the right method given your context.

Methods That Change Position and Reorder List

• eloquentModel.insertAt(2)
• eloquentModel.moveLower() will do nothing if the item is the lowest item
• eloquentModel.moveHigher() will do nothing if the item is the highest item
• eloquentModel.moveToBottom()
• eloquentModel.moveToTop()
• eloquentModel.removeFromList()

Methods That Change Position Without Reordering List Immediately

Note: a changed position will still trigger updates to other items in the list once the model is saved

• eloquentModel.incrementPosition()
• eloquentModel.decrementPosition()
• eloquentModel.setListPosition(3)

Methods That Return Attributes of the Item's List Position

• eloquentModel.isFirst()
• eloquentModel.isLast()
• eloquentModel.isInList()
• eloquentModel.isNotInList()
• eloquentModel.isDefaultPosition()
• eloquentModel.higherItem()
• eloquentModel.higherItems() will return all the items above eloquentModel in the list (ordered by the position, ascending)
• eloquentModel.lowerItem()
• eloquentModel.lowerItems() will return all the items below eloquentModel in the list (ordered by the position, ascending)

##Configuration

There are a few configuration options available. You'll need to pass these in as an array argument for initListify() in your model's constructor. Here are the options:

• top_of_list sets the integer position for the top of the list (default: 1).
• column sets the name of your position column that you chose during installation (default: 'position').
• add_new_at sets the name of your position column that you chose during installation (default: 'bottom', options: 'top' or 'bottom').
• scope allows you to scope the items in your list. This one requires a bit of elaboration. There are three posible values accepted:
  • string
  • Illuminate\Database\Eloquent\Relations\BelongsTo object
  • Illuminate\Database\Query\Builder object

###String

If string is passed in, a raw string is passed in as a whereRaw to the scope. This allows you to do something like 'custom_foreign_key = 42' and have all of the items scoped to that result set. You can pass as complicated of a where clause as you want, and it will be passed straight into each DB operation.

Example:

class User extends Eloquent
{
    use \Lookitsatravis\Listify\Listify;

    public function __construct(array $attributes = array(), $exists = false) {

        parent::__construct($attributes, $exists);

        $this->initListify([
            'scope' => 'answer_to_ltuae = 42'
        ]);
    }
}

Results in a scope of:

WHERE answer_to_ltuae = 42

###Illuminate\Database\Eloquent\Relations\BelongsTo

If Illuminate\Database\Eloquent\Relations\BelongsTo is passed in, Listify will match up the foreign key of the scope to the value of the corresponding foreign key of the model instance.

Example:

class ToDoListItem extends Eloquent
{
    use \Lookitsatravis\Listify\Listify;

    public function __construct(array $attributes = array(), $exists = false) {

        parent::__construct($attributes, $exists);

        $this->initListify([
            'scope' => $this->toDoList()
        ]);
    }

    public function toDoList()
    {
        $this->belongsTo('ToDoList');
    }
}

Results in a scope of:

WHERE to_do_list_id = {{value of toDoListItem.to_do_list_id}}

###Illuminate\Database\Query\Builder

And lastly, if Illuminate\Database\Query\Builder is passed in, Listify will extract the where clause of the builder and use it as the scope of the Listify items. This scope type was added in an attempt to keep parity between the acts_as_list version and Listify; however, due to differences in the languages and in ActiveRecord versus Eloquent, it is a limited implementation so far and needs impovement to be more flexible and secure. This is a big limitation and will be the first thing addressed in upcoming releases.

This one is tricky, because in order for it to work the query objects where array is prepared with the bindings outside of PDO and then passed in as a raw string. So, please keep in mind that this route can open your application up to abuse if you are not careful about how the object is built. If you use direct user input, please sanitize the data before using this as a scope for Listify.

Example:

class ToDoListItem extends Eloquent
{
    use \Lookitsatravis\Listify\Listify;

    public function __construct(array $attributes = array(), $exists = false) {

        parent::__construct($attributes, $exists);

        $this->initListify([
            'scope' => DB::table($this->getTable())->where('type', '=', 'Not A List of My Favorite Porn Videos')
        ]);
    }
}

Results in a scope of:

to_do_list_items.type = 'Not A List of My Favorite Porn Videos'

Changing the configuration

You may also change any configuration value during runtime by using $this->setListifyConfig('key', 'value');. For example, to change the scope, you can do this:

$this->setListifyConfig('scope', 'what_does_the_fox_say = "ring ding ding ding"');

When an update is processed, the original scope will be used to remove the record from that list, and insert it into the new list scope. Be careful here. Changing the configuration during processing can have unpredictable effects.

Notes

All position queries (select, update, etc.) inside trait methods are executed without the default scope, this will prevent nasty issues when the default scope is different from Listify scope.

The position column is set after validations are called, so you should not put a presence validation on the position column.

Future Plans

• Add support for using a closure as a scope
• Update Illuminate\Database\Query\Builder scope to be more secure and flexible
• Additional features for the install command. Things like:
  • update the model with trait automatically (including init method in constructor)
  • generate (or add to) a controller with actions for each public method for Listify, including adding necessary routes. This would make it easy to, say, call something like http://localhost:8000/foos/1/move_lower through an AJAX-y front end.

Aside from that, I hope to just keep in parity with the Ruby gem acts_as_list (https://github.com/swanandp/acts_as_list) as necessary.

Contributing to Listify

• Check out the latest master to make sure the feature hasn't been implemented or the bug hasn't been fixed yet
• Check out the issue tracker to make sure someone already hasn't requested it and/or contributed it
• Fork the project
• Start a feature/bugfix branch
• Commit and push until you are happy with your contribution
• Make sure to add tests for it. This is important so I don't break it in a future version unintentionally.
• Please try not to mess with the Composer.json, version, or history. If you want to have your own version, or is otherwise necessary, that is fine, but please isolate to its own commit so I can cherry-pick around it.
• I would recommend using Laravel 5.0 and higher for testing the build before a pull request.

Copyright

Copyright (c) 2013-2017 Travis Vignon, released under the MIT license