uninitialized constant error when trying to update the image file - ruby

Question

I am trying to use and learn carrierwave. My problem is that I am able to upload files, but when trying to edit them I am getting the error uninitialized constant ImageFile
Heres my images_controller.rb
class ImagesController < ApplicationController
before_action :set_image, only: [:show, :edit, :update, :destroy]
# GET /images
# GET /images.json
def index
#images = Image.all
end
# GET /images/1
# GET /images/1.json
def show
end
# GET /images/new
def new
#image = Image.new
end
# GET /images/1/edit
def edit
end
# POST /images
# POST /images.json
def create
#image = Image.new(image_params)
respond_to do |format|
if #image.save
format.html { redirect_to #image, notice: 'Image was successfully created.' }
format.json { render :show, status: :created, location: #image }
else
format.html { render :new }
format.json { render json: #image.errors, status: :unprocessable_entity }
end
end
end
# PATCH/PUT /images/1
# PATCH/PUT /images/1.json
def update
respond_to do |format|
if #image.update(image_params)
format.html { redirect_to #image, notice: 'Image was successfully updated.' }
format.json { render :show, status: :ok, location: #image }
else
format.html { render :edit }
format.json { render json: image.errors, status: :unprocessable_entity }
end
end
end
# DELETE /images/1
# DELETE /images/1.json
def destroy
#image.destroy
respond_to do |format|
format.html { redirect_to images_url, notice: 'Image was successfully destroyed.' }
format.json { head :no_content }
end
end
private
# Use callbacks to share common setup or constraints between actions.
def set_image
#image = Image.find(params[:id])
end
# Never trust parameters from the scary internet, only allow the white list through.
def image_params
params.require(:image).permit(:Title, :ImageFile, :Comments)
end
end
and this is the _form.html.erb used in both new and edit
<%= form_for #image, html: { multipart: true } do |f| %>
<% if #image.errors.any? %>
<div id="error_explanation">
<h2><%= pluralize(#image.errors.count, "error") %> prohibited this image from being saved:</h2>
<ul>
<% #image.errors.full_messages.each do |message| %>
<li><%= message %></li>
<% end %>
</ul>
</div>
<% end %>
<div class="field">
<%= f.label :Title %><br>
<%= f.text_field :Title %>
</div>
<div class="field">
<%= f.label :ImageFile %><br>
<%= f.file_field :ImageFile %>
</div>
<div class="field">
<%= f.label :Comments %><br>
<%= f.text_field :Comments %>
</div>
<div class="actions">
<%= f.submit %>
</div>
<% end %>
and here is the image.rb
class Image < ActiveRecord::Base
# attr_accessible :Comments, :ImageFile, :Title
mount_uploader :ImageFile, ImageCreatorUploader
end
please help

Answer 1

You have an error in your Image class. you are not mounting the uploader correctly. You are passing in a symbol of a classname to the mount_uploader method. You need to pass a symbol of the field name. Replace:
class Image < ActiveRecord::Base
mount_uploader :ImageFile, ImageCreatorUploader
end
With:
class Image < ActiveRecord::Base
mount_uploader :image_file, ImageCreatorUploader
end
Method names should not be capitalised. Only class names.
Also, since you are using strong_parameters, you don't need attr_accessible. You've commented the line out, but I figured I would point this out. You've also capitalised your attribute names here, which is not correct. Use snake_case.

Answer 2

In ruby, attribute names, variable names, method names should all start with a small letter. Names starting with Capital letters are considered constants, and class names.
Change all references to your class's attributes (:Title, :ImageFile, :Comments) to snake_case (:title, :image_file, :comments)