FeedMe Pro Import JSON

Question

When I import using JSON with FeedMe Pro and need to import more records into an entry that has a Matrix field. I find it deletes the previous and adds the new data only. Is there anyway to append to the Matrix field leaving the previous data intact?

Answer 1

In addition to How to save Matrix data programmatically in Craft 3

You'll fetch your data loop each row and fetch the element / create a new element if none exists

$section = Craft::$app->sections->getSectionByHandle('news');
$entryTypes = $section->getEntryTypes();
$entryType = reset($entryTypes);
foreach ($jsonData as $row) {
    // try to fetch an element
    $element = Craft::$app->getElements()->getElementById($row['id']);
    // no element exists, create a new one
    if ($element === null) {
        $element = new Entry(
            [
                'sectionId'     => $section->id,
                'typeId'        => $entryType->id,
                'fieldLayoutId' => $entryType->fieldLayoutId,
                'authorId'      => 1,
                'title'         => 'My Entry',
                'slug'          => 'my-entry',
                'postDate'      => new DateTime(),
            ]
        );
    }
    // get the field by handle
    /** @var \craft\fields\Matrix $field */
    $field = Craft::$app->getFields()->getFieldByHandle('matrix');

    // get the existing matrix blocks
    $existingMatrix = $element->getFieldValue('matrix');

    // serialize the data
    $serializedMatrix = $field->serializeValue($existingMatrix, $element);

   // loop your json matrix blocks
    foreach ($row['yourMatrixBlocks'] as $key => $block) {
        // append your new Matrix fields
        $serializedMatrix['new' . $key] = [
            'type'   => 'block',
            'fields' => [
                'field' => $block['field']
            ],
        ];
    }

    // set the new field value
    $element->setFieldValue('matrix', $serializedMatrix);
    $success = Craft::$app->getElements()->saveElement($element);

    // display errors - just in Case
    if($success === false){
        Craft::dd($element->getErrors());    
    }
}