NoMethodError - undefined method `file' for on simple query - ruby-on-rails

Question

I just want to show a picture but it always throws the same error. The join is correct but he doesn't show the image instead he throws that error.
Within the /series_images/ show and index the image is displayed with
<%= image_tag(#series_image.file, class: "img-responsive",) %>
That's working without any problems.
Here is the Server
Started GET "/series/beyond-the-boundary" for 127.0.0.1 at 2016-01-06 01:44:03 +0100
Processing by SeriesController#show as HTML
Parameters: {"id"=>"beyond-the-boundary"}
Series Load (0.3ms) SELECT "series".* FROM "series" WHERE "series"."slug" = $1 ORDER BY "series"."id" ASC LIMIT 1 [["slug", "beyond-the-boundary"]]
SeriesImage Load (0.3ms) SELECT "series_images".* FROM "series_images" WHERE "series_images"."series_id" = $1 [["series_id", 1]]
Rendered series/show.html.erb within layouts/application (3.4ms)
Completed 500 Internal Server Error in 7ms (ActiveRecord: 0.5ms)
NoMethodError - undefined method `file' for #<SeriesImage::ActiveRecord_Associations_CollectionProxy:0x007fc0e70be6e0>:
activerecord (4.2.5) lib/active_record/relation/delegation.rb:136:in `method_missing'
activerecord (4.2.5) lib/active_record/relation/delegation.rb:99:in `method_missing'
app/views/series/show.html.erb:2:in `_app_views_series_show_html_erb__1653679829410534096_70233272992260'
actionview (4.2.5) lib/action_view/template.rb:145:in `block in render'
activesupport (4.2.5) lib/active_support/notifications.rb:166:in `instrument'
actionview (4.2.5) lib/action_view/template.rb:333:in `instrument'
actionview (4.2.5) lib/action_view/template.rb:143:in `render'
actionview (4.2.5) lib/action_view/renderer/template_renderer.rb:54:in `block (2 levels) in render_template'
actionview (4.2.5) lib/action_view/renderer/abstract_renderer.rb:39:in `block in instrument'
activesupport (4.2.5) lib/active_support/notifications.rb:164:in `block in instrument'
activesupport (4.2.5) lib/active_support/notifications/instrumenter.rb:20:in `instrument'
activesupport (4.2.5) lib/active_support/notifications.rb:164:in `instrument'
actionview (4.2.5) lib/action_view/renderer/abstract_renderer.rb:39:in `instrument'
actionview (4.2.5) lib/action_view/renderer/template_renderer.rb:53:in `block in render_template'
actionview (4.2.5) lib/action_view/renderer/template_renderer.rb:61:in `render_with_layout'
actionview (4.2.5) lib/action_view/renderer/template_renderer.rb:52:in `render_template'
actionview (4.2.5) lib/action_view/renderer/template_renderer.rb:14:in `render'
actionview (4.2.5) lib/action_view/renderer/renderer.rb:42:in `render_template'
actionview (4.2.5) lib/action_view/renderer/renderer.rb:23:in `render'
actionview (4.2.5) lib/action_view/rendering.rb:100:in `_render_template'
actionpack (4.2.5) lib/action_controller/metal/streaming.rb:217:in `_render_template'
actionview (4.2.5) lib/action_view/rendering.rb:83:in `render_to_body'
actionpack (4.2.5) lib/action_controller/metal/rendering.rb:32:in `render_to_body'
actionpack (4.2.5) lib/action_controller/metal/renderers.rb:37:in `render_to_body'
actionpack (4.2.5) lib/abstract_controller/rendering.rb:25:in `render'
actionpack (4.2.5) lib/action_controller/metal/rendering.rb:16:in `render'
actionpack (4.2.5) lib/action_controller/metal/instrumentation.rb:44:in `block (2 levels) in render'
activesupport (4.2.5) lib/active_support/core_ext/benchmark.rb:12:in `block in ms'
/Users/woorari/.rbenv/versions/2.2.3/lib/ruby/2.2.0/benchmark.rb:303:in `realtime'
activesupport (4.2.5) lib/active_support/core_ext/benchmark.rb:12:in `ms'
actionpack (4.2.5) lib/action_controller/metal/instrumentation.rb:44:in `block in render'
actionpack (4.2.5) lib/action_controller/metal/instrumentation.rb:87:in `cleanup_view_runtime'
activerecord (4.2.5) lib/active_record/railties/controller_runtime.rb:25:in `cleanup_view_runtime'
actionpack (4.2.5) lib/action_controller/metal/instrumentation.rb:43:in `render'
actionpack (4.2.5) lib/action_controller/metal/implicit_render.rb:10:in `default_render'
actionpack (4.2.5) lib/action_controller/metal/implicit_render.rb:5:in `send_action'
actionpack (4.2.5) lib/abstract_controller/base.rb:198:in `process_action'
actionpack (4.2.5) lib/action_controller/metal/rendering.rb:10:in `process_action'
actionpack (4.2.5) lib/abstract_controller/callbacks.rb:20:in `block in process_action'
activesupport (4.2.5) lib/active_support/callbacks.rb:117:in `call'
activesupport (4.2.5) lib/active_support/callbacks.rb:555:in `block (2 levels) in compile'
activesupport (4.2.5) lib/active_support/callbacks.rb:505:in `call'
activesupport (4.2.5) lib/active_support/callbacks.rb:92:in `__run_callbacks__'
activesupport (4.2.5) lib/active_support/callbacks.rb:778:in `_run_process_action_callbacks'
activesupport (4.2.5) lib/active_support/callbacks.rb:81:in `run_callbacks'
actionpack (4.2.5) lib/abstract_controller/callbacks.rb:19:in `process_action'
actionpack (4.2.5) lib/action_controller/metal/rescue.rb:29:in `process_action'
actionpack (4.2.5) lib/action_controller/metal/instrumentation.rb:32:in `block in process_action'
activesupport (4.2.5) lib/active_support/notifications.rb:164:in `block in instrument'
activesupport (4.2.5) lib/active_support/notifications/instrumenter.rb:20:in `instrument'
activesupport (4.2.5) lib/active_support/notifications.rb:164:in `instrument'
actionpack (4.2.5) lib/action_controller/metal/instrumentation.rb:30:in `process_action'
actionpack (4.2.5) lib/action_controller/metal/params_wrapper.rb:250:in `process_action'
activerecord (4.2.5) lib/active_record/railties/controller_runtime.rb:18:in `process_action'
actionpack (4.2.5) lib/abstract_controller/base.rb:137:in `process'
actionview (4.2.5) lib/action_view/rendering.rb:30:in `process'
actionpack (4.2.5) lib/action_controller/metal.rb:196:in `dispatch'
actionpack (4.2.5) lib/action_controller/metal/rack_delegation.rb:13:in `dispatch'
actionpack (4.2.5) lib/action_controller/metal.rb:237:in `block in action'
actionpack (4.2.5) lib/action_dispatch/routing/route_set.rb:76:in `dispatch'
actionpack (4.2.5) lib/action_dispatch/routing/route_set.rb:45:in `serve'
actionpack (4.2.5) lib/action_dispatch/journey/router.rb:43:in `block in serve'
actionpack (4.2.5) lib/action_dispatch/journey/router.rb:30:in `serve'
actionpack (4.2.5) lib/action_dispatch/routing/route_set.rb:817:in `call'
warden (1.2.4) lib/warden/manager.rb:35:in `block in call'
warden (1.2.4) lib/warden/manager.rb:34:in `call'
rack (1.6.4) lib/rack/etag.rb:24:in `call'
rack (1.6.4) lib/rack/conditionalget.rb:25:in `call'
rack (1.6.4) lib/rack/head.rb:13:in `call'
actionpack (4.2.5) lib/action_dispatch/middleware/params_parser.rb:27:in `call'
actionpack (4.2.5) lib/action_dispatch/middleware/flash.rb:260:in `call'
rack (1.6.4) lib/rack/session/abstract/id.rb:225:in `context'
rack (1.6.4) lib/rack/session/abstract/id.rb:220:in `call'
actionpack (4.2.5) lib/action_dispatch/middleware/cookies.rb:560:in `call'
activerecord (4.2.5) lib/active_record/query_cache.rb:36:in `call'
activerecord (4.2.5) lib/active_record/connection_adapters/abstract/connection_pool.rb:653:in `call'
activerecord (4.2.5) lib/active_record/migration.rb:377:in `call'
actionpack (4.2.5) lib/action_dispatch/middleware/callbacks.rb:29:in `block in call'
activesupport (4.2.5) lib/active_support/callbacks.rb:88:in `__run_callbacks__'
activesupport (4.2.5) lib/active_support/callbacks.rb:778:in `_run_call_callbacks'
activesupport (4.2.5) lib/active_support/callbacks.rb:81:in `run_callbacks'
actionpack (4.2.5) lib/action_dispatch/middleware/callbacks.rb:27:in `call'
actionpack (4.2.5) lib/action_dispatch/middleware/reloader.rb:73:in `call'
actionpack (4.2.5) lib/action_dispatch/middleware/remote_ip.rb:78:in `call'
better_errors (2.1.1) lib/better_errors/middleware.rb:84:in `protected_app_call'
better_errors (2.1.1) lib/better_errors/middleware.rb:79:in `better_errors_call'
better_errors (2.1.1) lib/better_errors/middleware.rb:57:in `call'
actionpack (4.2.5) lib/action_dispatch/middleware/debug_exceptions.rb:17:in `call'
web-console (2.2.1) lib/web_console/middleware.rb:39:in `call'
actionpack (4.2.5) lib/action_dispatch/middleware/show_exceptions.rb:30:in `call'
railties (4.2.5) lib/rails/rack/logger.rb:38:in `call_app'
railties (4.2.5) lib/rails/rack/logger.rb:20:in `block in call'
activesupport (4.2.5) lib/active_support/tagged_logging.rb:68:in `block in tagged'
activesupport (4.2.5) lib/active_support/tagged_logging.rb:26:in `tagged'
activesupport (4.2.5) lib/active_support/tagged_logging.rb:68:in `tagged'
railties (4.2.5) lib/rails/rack/logger.rb:20:in `call'
actionpack (4.2.5) lib/action_dispatch/middleware/request_id.rb:21:in `call'
rack (1.6.4) lib/rack/methodoverride.rb:22:in `call'
rack (1.6.4) lib/rack/runtime.rb:18:in `call'
activesupport (4.2.5) lib/active_support/cache/strategy/local_cache_middleware.rb:28:in `call'
rack (1.6.4) lib/rack/lock.rb:17:in `call'
actionpack (4.2.5) lib/action_dispatch/middleware/static.rb:116:in `call'
rack (1.6.4) lib/rack/sendfile.rb:113:in `call'
railties (4.2.5) lib/rails/engine.rb:518:in `call'
railties (4.2.5) lib/rails/application.rb:165:in `call'
rack (1.6.4) lib/rack/lock.rb:17:in `call'
rack (1.6.4) lib/rack/content_length.rb:15:in `call'
rack (1.6.4) lib/rack/handler/webrick.rb:88:in `service'
/Users/woorari/.rbenv/versions/2.2.3/lib/ruby/2.2.0/webrick/httpserver.rb:138:in `service'
/Users/woorari/.rbenv/versions/2.2.3/lib/ruby/2.2.0/webrick/httpserver.rb:94:in `run'
/Users/woorari/.rbenv/versions/2.2.3/lib/ruby/2.2.0/webrick/server.rb:294:in `block in start_thread'
Started POST "/__better_errors/a376ff2bf7c7dd19/variables" for 127.0.0.1 at 2016-01-06 01:44:03 +0100
The call happen within the series/show.html.erb
<%= image_tag(#series.series_image.file, class: "img-responsive",) %>
<p>
<strong>Name:</strong>
<%= #series.name %>
</p>
Series Controller
class SeriesController < ApplicationController
before_action :set_series, only: [:show, :edit, :update, :destroy]
# GET /series
# GET /series.json
def index
#series = Series.paginate(:page => params[:page], :per_page => 10)
end
# GET /series/1
# GET /series/1.json
def show
end
# GET /series/new
def new
#series = Series.new
end
# GET /series/1/edit
def edit
end
# POST /series
# POST /series.json
def create
#series = Series.new(series_params)
respond_to do |format|
if #series.save
format.html { redirect_to #series, notice: 'Series was successfully created.' }
format.json { render :show, status: :created, location: #series }
else
format.html { render :new }
format.json { render json: #series.errors, status: :unprocessable_entity }
end
end
end
# PATCH/PUT /series/1
# PATCH/PUT /series/1.json
def update
respond_to do |format|
if #series.update(series_params)
format.html { redirect_to #series, notice: 'Series was successfully updated.' }
format.json { render :show, status: :ok, location: #series }
else
format.html { render :edit }
format.json { render json: #series.errors, status: :unprocessable_entity }
end
end
end
# DELETE /series/1
# DELETE /series/1.json
def destroy
#series.destroy
respond_to do |format|
format.html { redirect_to series_index_url, notice: 'Series was successfully destroyed.' }
format.json { head :no_content }
end
end
private
# Use callbacks to share common setup or constraints between actions.
def set_series
#series = Series.friendly.find(params[:id])
end
# Never trust parameters from the scary internet, only allow the white list through.
def series_params
params.require(:series).permit(:name, :tagline, :shortDESC, :longDESC, :rating, :release)
end
end
SeriesImage Controller
class SeriesImagesController < ApplicationController
before_action :set_series_image, only: [:show, :edit, :update, :destroy]
# GET /series_images
# GET /series_images.json
def index
#series_images = SeriesImage.paginate(:page => params[:page], :per_page => 5)
end
# GET /series_images/1
# GET /series_images/1.json
def show
end
# GET /series_images/new
def new
#series_image = SeriesImage.new
end
# GET /series_images/1/edit
def edit
end
# POST /series_images
# POST /series_images.json
def create
#series_image = SeriesImage.new(series_image_params)
respond_to do |format|
if #series_image.save
format.html { redirect_to #series_image, notice: 'Series image was successfully created.' }
format.json { render :show, status: :created, location: #series_image }
else
format.html { render :new }
format.json { render json: #series_image.errors, status: :unprocessable_entity }
end
end
end
# PATCH/PUT /series_images/1
# PATCH/PUT /series_images/1.json
def update
respond_to do |format|
if #series_image.update(series_image_params)
format.html { redirect_to #series_image, notice: 'Series image was successfully updated.' }
format.json { render :show, status: :ok, location: #series_image }
else
format.html { render :edit }
format.json { render json: #series_image.errors, status: :unprocessable_entity }
end
end
end
# DELETE /series_images/1
# DELETE /series_images/1.json
def destroy
#series_image.destroy
respond_to do |format|
format.html { redirect_to series_images_url, notice: 'Series image was successfully destroyed.' }
format.json { head :no_content }
end
end
private
# Use callbacks to share common setup or constraints between actions.
def set_series_image
#series_image = SeriesImage.find(params[:id])
end
# Never trust parameters from the scary internet, only allow the white list through.
def series_image_params
params.require(:series_image).permit(:series_id, :file, :desc, :head, :headID, :home, :homeID)
end
end
The 2 Models
class Series < ActiveRecord::Base
extend FriendlyId
friendly_id :name, use: :slugged
validates :name, presence: true
has_many :series_images
end
class SeriesImage < ActiveRecord::Base
mount_uploader :file, PictureUploader
belongs_to :series
end
The gemfile
#better IDs
gem 'friendly_id', '~> 5.1'
#Bootstrap
gem 'bootstrap-sass', '~> 3.3', '>= 3.3.6'
#Image Upload
gem 'carrierwave', '~> 0.10.0'
#Bootswatch
gem 'bootswatch-rails', '~> 3.3', '>= 3.3.5'
# Devise User Management
gem 'devise', '~> 3.5', '>= 3.5.3'
#Pagination
gem 'will_paginate', '~> 3.1'
gem 'will_paginate-bootstrap', '~> 1.0', '>= 1.0.1'
The Migration of Series_Images
class CreateSeriesImages < ActiveRecord::Migration
def change
create_table :series_images do |t|
t.belongs_to :series, index:true
t.string :file
t.string :desc
t.boolean :head
t.integer :headID
t.boolean :home
t.integer :homeID
t.timestamps null: false
end
end
end

Answer 1

The problem is that you have a one to many relationship between Series and SeriesImages. So when you call #series.series_image in the view you are getting an active record collection back instead of a specific image. You could try doing #series.series_image.first.try(:file) and that would give you the first series_image if it exist. If this fails it will return nil.
Is a Series supposed to have multiple SeriesImages?