Single media/file attachment: attachOne

With the attachOne function files like images, movies or documents can be attached to a record of a database table. Media attachments are using built-in relations of OctoberCMS. So it is very easy to implement them.

This is what a record with an attached file - an image in this case - will look like.

Prerequisites are

• an installed builder plugin
• any source code editor or e.g. the Developer Tools plugin with built-in Code editor like in the screenshoots
• a database table for records to attach the media to
• a form (at least in backend) to display the media
• some media already uploaded to the media manager or ready to do so

Required skills

• how to work with builder
• how to create a plugin with builder
• how to create tables and forms with builder

The base model requires to know the type of desired relation as well as the name of the relation. This name can be seen like a field name of a database-table.

The base model is located in the plugin directory, subdirectory models using the singular of the related db-table name. In our library example this is:

  /pds/library/models/book.php

Here, the attachOne relation has to be inserted:

These are the lines of code to add (comments are not necessary, of course, but they will help to maintain the code):

    // add a relation for a SINGLE image, field name is 'cover'
    // this table must not have a field named 'cover' !
    public $attachOne = [
        'cover' => ['System\Models\File', 'public' => false]
    ];

Next step is to complete the form with an additional field to upload and display media and/or files:

Finally, in the backend form view of the plugin, a file can be uploaded by clicking on the file upload symbol - the area below the 'Cover Image' title in the example: