ActionController::UnknownFormat when uploading image with Dropzone - ruby-on-rails

Question

I have a new error regarding my Dropzone JS snippet. I use dropzone to upload images from an #Edit view.
One the images are created by another controller create action, I redirect to that very edit action.
This is where I get this new error :
Completed 406 Not Acceptable in 14ms (ActiveRecord: 1.1ms)
ActionController::UnknownFormat (PhotographesController#edit is missing a template for this request format and variant.
request.formats: ["application/json"]
request.variant: []):
actionpack (5.2.0) lib/action_controller/metal/implicit_render.rb:42:in `default_render'
actionpack (5.2.0) lib/action_controller/metal/basic_implicit_render.rb:6:in `block in send_action'
actionpack (5.2.0) lib/action_controller/metal/basic_implicit_render.rb:6:in `tap'
actionpack (5.2.0) lib/action_controller/metal/basic_implicit_render.rb:6:in `send_action'
actionpack (5.2.0) lib/abstract_controller/base.rb:194:in `process_action'
.....
It used to work perfectly in the past. But since I have set this snippet in place I have done quite a few things: installing gem "serviceworker-rails" and deferring the javascript..
I have undeferred the Javascript but the error is still here. Is it related to the serviceworker gem ?
EDIT
Dropzone snippet inside Photographes#edit view (inline)
<script>
// Dropzone = dynamic
var AUTH_TOKEN=$('meta[name="csrf-token"]').attr('content');
Dropzone.autoDiscover = false;
var myDropzone = new Dropzone("div#mydropzone",{
url: "<%= photographe_photographephotos_path(#photographe.hashed_id) %>",
autoProcessQueue: false,
autoDiscover: false,
uploadMultiple: true,
addRemoveLinks: true,
// clickable: false,
parallelUploads: 12,
maxFilesize: 5,
maxFiles: 12,
acceptedFiles: 'image/jpg, image/jpeg, image/png',
params:{
'authenticity_token': AUTH_TOKEN
},
successmultiple: function(data,response){
$('#msgBoard').append(response.message).addClass("alert alert-success");
$('#msgBoard').delay(2000).fadeOut();
$('#fileslist').val(response.filesList);
$('#photographedit').off('submit').submit();
}
});
$('#photographedit').submit(function(e){
if(myDropzone.getQueuedFiles().length > 0){
e.preventDefault();
myDropzone.processQueue();
}
});
</script>
Then Photographephotos#create
def create
#photographe = Photographe.find_by(hashed_id: params[:photographe_hashed_id])
if params[:file].present?
uploaded_pics = params[:file]
maximum_images=12
available_images = maximum_images - #photographe.photographephotos.count
n_keys = uploaded_pics.keys.first(available_images)
filtered_pics = uploaded_pics.slice(*n_keys)
filtered_pics.each do |index,pic|
#image = #photographe.photographephotos.new
#image.image = pic
#image.image_file_name = "Copyright" + #photographe.professionnel.first_name.to_s + #photographe.professionnel.last_name.to_s + ".JPG"
#image.save
end
end
redirect_to edit_photographe_path(#photographe.hashed_id)
end
The redirect at the end returns (should return) to the Photographes#edit view. What is funny if it used to work properly ...
I see that people used to have same problem with Jbuilder as per github. I have updated Jbuilder gem with no success.
Also the pictures are properly updated by paperclip. I get this error from logs when the redirection fails at the end of the images creation.

Answer 1

It seems like the controller is trying to render a template in a format that doesn't exist, maybe you can try specifying the format explicitly like this:
redirect_to edit_photographe_path(#photographe.hashed_id), :format => :html
This may happen if you received a request in a specific format and want to render a template in a different one.
I'm not sure if, in your case, the :format option should go inside the _path() or the redirect_to() method. If the above doesn't work try this:
redirect_to edit_photographe_path(#photographe.hashed_id, :format => :html)