Laravel mutators are Model methods that process data in some way before it is stored in the database.

Potential use cases:

• Capitalising names before saving
• Title-casing titles
• Slugifying slugs
• Change date strings to Carbon objects
• Hashing passwords
• JSON encoding (possible in MySQL 5.7.8, coming soon in MariaDB)

To set up a Mutator, add a suitable method in the Model class. The database column is determined by the method name, which hence needs to be in a certain format:

set{ColumnName}Attribute

Note that the column name needs to be written in StudlyCaps (PascalCase) - the first letter of each sub-word (including the first) is capitalised.

A mutator that converts a string to title case, saved in the post_title column would look like this:

<?php
public function setPostTitleAttribute($title)
    {
      $this->attributes['post_title'] = ucwords($title);
    }

Note that the method doesn’t return anything - it just directly accesses the atribute and “mutates” the value.

References

• Laravel Docs, Mutators
• Good article on Accessors and Mutators