rails paperclip - trouble uploading multiple images to one model through nested model - ruby-on-rails

Question

I have been trying to figure out how to upload multiple images to one model through a nested model for a while now with no luck. I have a Project model, and for each project i would like to upload multiple images. I created a model called Picture and nested it within the Project model, and have set up paperclip and everything seems fine except when I upload an image and click on "Create project", the image does not show on the "show" page. There is no error message displayed. Please help as I do not know how to proceed from here.
here is my code:
Project form:
<%= bootstrap_nested_form_for #project, :html => {:multipart => true} do |f| %>
<% f.fields_for :pictures do |builder| %>
<% if builder.object.new_record? %>
<p>
<%= builder.file_field :image %>
</p>
<% end %>
<%= builder.link_to_remove "Remove" %>
<% end %>
<p>
<%= f.link_to_add "Add Images", :pictures %>
</p>
<%= f.submit %>
<% end %>
Project controller:-
class ProjectsController < ApplicationController
before_action :set_project, only: [:show, :edit, :update, :destroy]
respond_to :html
def index
#projects = Project.all
respond_with(#projects)
end
def show
respond_with(#project)
end
def new
#project = Project.new
#project.pictures.build
respond_with(#project)
end
def edit
#project = Project.find(params[:id])
#project.pictures.build
end
def create
#project = Project.new(project_params)
if #project.save
flash[:notice] = "Successfully created project."
redirect_to #project
else
render :action => 'new'
end
end
def update
#project.update(project_params)
respond_with(#project)
end
def destroy
#project.destroy
respond_with(#project)
end
private
def set_project
#project = Project.find(params[:id])
end
def project_params
params.require(:project).permit(:id, :title, :description, :status, :phase, :location, pictures_attributes: [:id, :image])
end
end
Projects model:-
class Project < ActiveRecord::Base
has_many :pictures, :dependent => :destroy
accepts_nested_attributes_for :pictures, :reject_if => lambda { |t| t['picture'].nil? }
end
Pictures model:-
class Picture < ActiveRecord::Base
belongs_to :project
has_one :image
has_attached_file :image,
:path => ":rails_root/public/system/:attachment/:id/:style/:filename",
:url => "/system/:attachment/:id/:style/:filename",
:styles => { :medium => "300x300>", :thumb => "100x100>" }
validates_attachment_content_type :image, :content_type => ["image/jpg", "image/jpeg", "image/png", "image/gif"]
end
Show page:-
<% #project.pictures do |picture| %>
<%= image_tag picture.image_url %>
<% end %>
<p>
<strong>Title:</strong>
<%= #project.title %>
</p>
<p>
<strong>Description:</strong>
<%= #project.description %>
</p>
<p>
<strong>Status:</strong>
<%= #project.status %>
</p>
<p>
<strong>Phase:</strong>
<%= #project.phase %>
</p>
<p>
<strong>Location:</strong>
<%= #project.location %>
</p>
<%= link_to 'Edit', edit_project_path(#project) %> |
<%= link_to 'Back', projects_path %>
schema :-
ActiveRecord::Schema.define(version: 20150728092717) do
create_table "pictures", force: true do |t|
t.datetime "created_at"
t.datetime "updated_at"
t.string "image_file_name"
t.string "image_content_type"
t.integer "image_file_size"
t.datetime "image_updated_at"
t.integer "project_id"
end
add_index "pictures", ["project_id"], name: "index_pictures_on_project_id"
create_table "projects", force: true do |t|
t.string "title"
t.text "description"
t.string "status"
t.string "phase"
t.string "location"
t.datetime "created_at"
t.datetime "updated_at"
end

Answer 1

Your form and whitelist uses the property name image.
But you are rejecting any nested pictures if they don't have the picture param.
accepts_nested_attributes_for :pictures, :reject_if => lambda { |t| t['picture'].nil? }
Nested attributes params are not wrapped in a "model key" like rails form params usually are. This is what they look like:
params = {
project: {
pictures_attributes: [
{
image: 'foo.jpg'
}
]
}
}
You can catch these kind of errors quite simply with model specs:
require 'rails_helper'
RSpec.describe Project do
it 'accepts nested pictures' do
project = Project.new(pictures_attributes: [{ image: 'foo.jpg' }])
expect(project.pictures.first).to to_be_a Picture
end
end