Laravel array validation: use field index in error message - laravel

Question

I'm trying to validate a field array, and I'd like to point out which field is wrong in the validation errors.
I have a form to upload multiple images. For each image, there must be a caption and the alt attribute for HTML. If I try to upload 3 images and miss the fields for two of them, I'll get an error message like the following:
The field 'image file' is required.
The field 'image caption' is required.
The field 'image alt' is required.
The field 'image caption' is required.
The field 'image alt' is required.
The field 'image file' is required.
The problem is that the :attribute is repeated and if the user wants to update multiple images he/she will have to check all of them to find which field is missing!
What I want is this:
The field 'image file (item 1)' is required.
The field 'image caption (item 1)' is required.
The field 'image alt (item 1)' is required.
The field 'image caption (item 3)' is required.
The field 'image alt (item 3)' is required.
The field 'image file (item 1)' is required.
So the user can know where to fix the problem.
First, I tried this:
$attributes = [
'img.*.file' => 'Image file (item :* )',
'img.*.alt' => 'Image alt (item :* )',
'img.*.caption' => 'Image caption (item :* )',
];
//
$this->validate($request, $rules, [], $attributes);
I supposed that the :* would be replaced by the index of the field (1, 2, 3, 4, etc) as the same way :attribute is replaced by the attribute. However, the :* is not replaced by the index of the fields; instead, it is displayed as plain text.
It worths to note that I designed the code in such way that the HTML name attribute is indexed sequentially for all fields (img[1][alt], [img][2][alt], etc, img[1][caption], [img][2][caption], etc), so each field has the right index. Having that in mind, I suppose there is a way to get the index and use to create custom attributes in the error messages.
I searched for this problem and found the same question here Validation on fields using index position, but it uses angular, not laravel.
How can I get the index and put it in the attribute?If that is not possible, is there any other way to accomplish the desirable result without having to set up the error messages?
I would like to change the attributes and keep the default error messages that laravel provides

Answer 1

Try this example
$input = Request::all();
$rules = array(
'name' => 'required',
'location' => 'required',
'capacity' => 'required',
'description' => 'required',
'image' => 'required|array'
);
$validator = Validator::make($input, $rules);
if ($validator->fails()) {
$messages = $validator->messages();
return Redirect::to('venue-add')
->withErrors($messages);
}
$imageRules = array(
'image' => 'image|max:2000'
);
foreach($input['image'] as $image)
{
$image = array('image' => $image);
$imageValidator = Validator::make($image, $imageRules);
if ($imageValidator->fails()) {
$messages = $imageValidator->messages();
return Redirect::to('venue-add')
->withErrors($messages);
}
}

Answer 2

Thanks to the user sss S, I could implement his/her ideas to solve the problem.
Here is the code for the store method. It replaces (item) with (item $i) in the error message, where $i is the index of the field. Therefore the user can know exactly where is the error.
public function store(Request $request)
{
$rules = $this->rules();
$attributes = $this->attributes();
$validator = Validator::make($request->all(), $rules, [], $attributes);
$errors = [];
if ($validator->fails()) {
$errors = $validator->errors()->all();
}
$imgRules = [
'file' => 'required|image|mimes:jpeg,jpg,webp,png|max:1999',
'alt' => 'required|string|max:100|min:5',
'caption' => 'required|string|max:100|min:5',
];
$imgAttributes = [
'alt' => 'HTML alt attribute (item)',
'caption' => 'Caption(item)',
'file' => 'image file (item)',
];
foreach($request->img as $i => $img) {
$imgValidator = Validator::make($img, $imgRules, [], $imgAttributes);
$imgErrors = [];
if($imgValidator->fails()) {
$imgErrors = $imgValidator->errors()->all();
}
foreach($imgErrors as $k => $v) {
$imgErrors[$k] = str_replace('(item)', "(item $i)", $v);
}
$errors = array_merge($errors, $imgErrors);
}
if(count($errors) > 0) {
return response()->json(['success' => false, 'errors' => $errors]);
}
// here is the code store the new resource
// ...
// then return success message
}