Laravel Bitflags

Store and receive bitflags from a single database column.

Installation

composer require aw-studio/bitflags

Usage

Imagine you want to store multiple status flags in a single status(int) column of your Email model. This can be achieved using bitwise operations to create a representative bitmask. In order to enable bitwise operations bitflags MUST all be powers of two (1,2,4,8,16 …). You should also make shure to properly cast the column as Bitflags::class.

class Email extends Model
{
    // Email status flags, all powers of 2
    public const SENT = 1;
    public const RECEIVED = 2;
    public const SEEN = 4;
    public const READ = 8;

    protected $fillable = ['status'];

    public $casts = [
        'status' => Bitflags::class
    ];
}

Adding a flag to a bitmask

Adding a bitflag to a bitmask can be achieved using the addBitflag() helper:

public function markRead()
{
    $this->update([
        'status' => addBitflag(self::READ, $this->status)
    ]);
}

You can also add multiple flags at once:

$this->update([
    'status' => addBitflag([self::READ, self::SEEN], $this->status)
]);

Removing a flag from a bitmask

Removing a bitflag from a bitmask can be achieved using the removeBitflag() helper:

public function markUnread()
{
    $this->update([
        'status' => removeBitflag(self::READ, $this->status)
    ]);
}

Remove multiple flags at once:

$this->update([
    'status' => removeBitflag([self::READ, self::SEEN], $this->status)
]);

Query bitflags

To check if bitflags are included in a bitmask you may use the following query methods:

public function scopeRead($query)
{
    return $this->whereBitflag('status', self::READ);
}
public function scopeUnread($query)
{
    return $this->whereBitflagNot('status', self::READ);
}
public function scopeSeenOrRead($query)
{
    return $this->whereBitflagIn('status', [self::READ, self::SEEN]);
}
public function scopeSeenAndRead($query)
{
    return $this->whereBitflags('status', [self::READ, self::SEEN]);
}

Accessors

In order to get single flag attributes you can prepare accessors as follows:

protected $appends = ['read'];

public function getReadAttribute()
{
    return inBitmask(self::READ, $this->status);
}