@silverstripe.com)
*/
abstract class BulkLoader extends ViewableData
{
/**
* Each row in the imported dataset should map to one instance
* of this class (with optional property translation
* through {@self::$columnMaps}.
*
* @var string
*/
public $objectClass;
/**
* Override this on subclasses to give the specific functions names.
*
* @var string
*/
public static $title;
/**
* Map columns to DataObject-properties.
* If not specified, we assume the first row
* in the file contains the column headers.
* The order of your array should match the column order.
*
* The column count should match the count of array elements,
* fill with NULL values if you want to skip certain columns.
*
* You can also combine {@link $hasHeaderRow} = true and {@link $columnMap}
* and omit the NULL values in your map.
*
* Supports one-level chaining of has_one relations and properties with dot notation
* (e.g. Team.Title). The first part has to match a has_one relation name
* (not necessarily the classname of the used relation).
*
*
* 'FirstName', // custom column name
* null, // ignored column
* 'RegionID', // direct has_one/has_many ID setting
* 'OrganisationTitle', // create has_one relation to existing record using $relationCallbacks
* 'street' => 'Organisation.StreetName', // match an existing has_one or create one and write property.
* );
* ?>
*
*
* @var array
*/
public $columnMap = array();
/**
* Find a has_one relation based on a specific column value.
*
*
* array(
* 'relationname' => 'Organisation', // relation accessor name
* 'callback' => 'getOrganisationByTitle',
* );
* );
* ?>
*
*
* @var array
*/
public $relationCallbacks = array();
/**
* Specifies how to determine duplicates based on one or more provided fields
* in the imported data, matching to properties on the used {@link DataObject} class.
* Alternatively the array values can contain a callback method (see example for
* implementation details). The callback method should be defined on the source class.
*
* NOTE: If you're trying to get a unique Member record by a particular field that
* isn't Email, you need to ensure that Member is correctly set to the unique field
* you want, as it will merge any duplicates during {@link Member::onBeforeWrite()}.
*
* {@see Member::$unique_identifier_field}.
*
* If multiple checks are specified, the first non-empty field "wins".
*
*
* 'ID',
* 'phonenumber' => array(
* 'callback' => 'getByImportedPhoneNumber'
* )
* );
* ?>
*
*
* @var array
*/
public $duplicateChecks = array();
/**
* @var Boolean $clearBeforeImport Delete ALL records before importing.
*/
public $deleteExistingRecords = false;
public function __construct($objectClass)
{
$this->objectClass = $objectClass;
parent::__construct();
}
/*
* Load the given file via {@link self::processAll()} and {@link self::processRecord()}.
* Optionally truncates (clear) the table before it imports.
*
* @return BulkLoader_Result See {@link self::processAll()}
*/
public function load($filepath)
{
Environment::increaseTimeLimitTo(3600);
Environment::increaseMemoryLimitTo('512M');
//get all instances of the to be imported data object
if ($this->deleteExistingRecords) {
DataObject::get($this->objectClass)->removeAll();
}
return $this->processAll($filepath);
}
/**
* Preview a file import (don't write anything to the database).
* Useful to analyze the input and give the users a chance to influence
* it through a UI.
*
* @param string $filepath Absolute path to the file we're importing
* @return array See {@link self::processAll()}
*/
abstract public function preview($filepath);
/**
* Process every record in the file
*
* @param string $filepath Absolute path to the file we're importing (with UTF8 content)
* @param boolean $preview If true, we'll just output a summary of changes but not actually do anything
* @return BulkLoader_Result A collection of objects which are either created, updated or deleted.
* 'message': free-text string that can optionally provide some more information about what changes have
*/
abstract protected function processAll($filepath, $preview = false);
/**
* Process a single record from the file.
*
* @param array $record An map of the data, keyed by the header field defined in {@link self::$columnMap}
* @param array $columnMap
* @param $result BulkLoader_Result (passed as reference)
* @param boolean $preview
*/
abstract protected function processRecord($record, $columnMap, &$result, $preview = false);
/**
* Return a FieldList containing all the options for this form; this
* doesn't include the actual upload field itself
*/
public function getOptionFields()
{
}
/**
* Return a human-readable name for this object.
* It defaults to the class name can be overridden by setting the static variable $title
*
* @return string
*/
public function Title()
{
$title = $this->stat('title');
return $title ?: static::class;
}
/**
* Get a specification of all available columns and relations on the used model.
* Useful for generation of spec documents for technical end users.
*
* Return Format:
*
* array(
* 'fields' => array('myFieldName'=>'myDescription'),
* 'relations' => array('myRelationName'=>'myDescription'),
* )
*
*
* @todo Mix in custom column mappings
*
* @return array
**/
public function getImportSpec()
{
$spec = array();
// get database columns (fieldlabels include fieldname as a key)
// using $$includerelations flag as false, so that it only contain $db fields
$spec['fields'] = (array)singleton($this->objectClass)->fieldLabels(false);
$has_ones = singleton($this->objectClass)->hasOne();
$has_manys = singleton($this->objectClass)->hasMany();
$many_manys = singleton($this->objectClass)->manyMany();
$spec['relations'] = (array)$has_ones + (array)$has_manys + (array)$many_manys;
return $spec;
}
/**
* Determines if a specific field is null.
* Can be useful for unusual "empty" flags in the file,
* e.g. a "(not set)" value.
* The usual {@link DBField::isNull()} checks apply when writing the {@link DataObject},
* so this is mainly a customization method.
*
* @param mixed $val
* @param string $fieldName Name of the field as specified in the array-values for {@link self::$columnMap}.
* @return boolean
*/
protected function isNullValue($val, $fieldName = null)
{
return (empty($val) && $val !== '0');
}
}