silverstripe-framework/docs/en/02_Developer_Guides/11_Integration/How_Tos/custom_csvbulkloader.md

---
title: A custom CSVBulkLoader instance
summary: Customise your data importing
icon: upload
---

# How to: A custom CSVBulkLoader instance

A an implementation of a custom `CSVBulkLoader` loader. In this example. we're provided with a unique CSV file 
containing a list of football players and the team they play for. The file we have is in the format like below.

```
"SpielerNummer", "Name", "Geburtsdatum", "Gruppe"
11, "John Doe", 1982-05-12,"FC Bayern"
12, "Jane Johnson", 1982-05-12,"FC Bayern"
13, "Jimmy Dole",,"Schalke 04"
```

This data needs to be imported into our application. For this, we have two `DataObjects` setup. `Player` contains 
information about the individual player and a relation set up for managing the `Team`. 

 **app/code/Player.php**.


```php
use SilverStripe\ORM\DataObject;

class Player extends DataObject 
{

   private static $db = [
      'PlayerNumber' => 'Int',
      'FirstName' => 'Text',
      'LastName' => 'Text',
      'Birthday' => 'Date'
   ];
 
   private static $has_one = [
      'Team' => 'FootballTeam'
   ];
}
```

**app/code/FootballTeam.php**


```php
use SilverStripe\ORM\DataObject;

class FootballTeam extends DataObject 
{  
   private static $db = [
      'Title' => 'Text'
   ];

   private static $has_many = [
      'Players' => 'Player'
   ];
}
```

Now going back to look at the CSV, we can see that what we're provided with does not match what our data model looks 
like, so we have to create a sub class of `CsvBulkLoader` to handle the unique file. Things we need to consider with
the custom importer are:

*  Convert property names (e.g Number to PlayerNumber) through providing a `$columnMap`.
*  Split a combined "Name" field into `FirstName` and `LastName` by calling `importFirstAndLastName` on the `Name` 
column
*  Prevent duplicate imports by a custom `$duplicateChecks` definition.
*  Create a `Team` automatically based on the `Gruppe` column and a entry for `$relationCallbacks`

Our final import looks like this.

**app/code/PlayerCsvBulkLoader.php**


```php
use SilverStripe\Dev\CsvBulkLoader;

class PlayerCsvBulkLoader extends CsvBulkLoader 
{

   public $columnMap = [
      'Number' => 'PlayerNumber',
      'Name' => '->importFirstAndLastName',
      'Geburtsdatum' => 'Birthday',
      'Gruppe' => 'Team.Title',
   ];

   public $duplicateChecks = [
      'SpielerNummer' => 'PlayerNumber'
   ];

   public $relationCallbacks = [
      'Team.Title' => [
         'relationname' => 'Team',
         'callback' => 'getTeamByTitle'
      ]
   ];

   public static function importFirstAndLastName(&$obj, $val, $record) 
   {
      $parts = explode(' ', $val);
      if(count($parts) != 2) return false;
      $obj->FirstName = $parts[0];
      $obj->LastName = $parts[1];
   }

   public static function getTeamByTitle(&$obj, $val, $record) 
   {
      return FootballTeam::get()->filter('Title', $val)->First();
   }
}
```

## Related

*  [CsvParser](api:SilverStripe\Dev\CsvParser)
*  [ModelAdmin](api:SilverStripe\Admin\ModelAdmin)