Cannot get my Articles controller to create a blog Article with a picture. I am using imagemagick and carrierwave

问题

My create action in ArticlesController seems fine if I create an Article without uploading a picture. However, if I try to upload a picture for an article, I get the error:

ActionController::UrlGenerationError in ArticlesController#create
No route matches {:action=>"show", :controller=>"articles", :id=>nil} missing required keys: [:id]

Here is my Articles controller:

class ArticlesController < ApplicationController

before_filter :require_login, only: [:new, :create, :edit, :update, :destroy]

def index
    @articles = Article.all
end

def show
  @article = Article.find(params[:id])
  @comment = Comment.new
 @comment.article_id = @article.id
end
def new
 @article = Article.new
end
def create
 @article = Article.new(article_params)
 @article.save
 redirect_to article_path(@article)

end

def edit
 @article = Article.find(params[:id])
end
def destroy
 @article = Article.find(params[:id])
 @article.destroy
 redirect_to articles_path
end
def update
 @article = Article.find(params[:id])
 @article.update(article_params)
 flash.notice = "Article '#{@article.title}' Updated!"
 redirect_to article_path(@article)
end




private
def article_params
 params.require(:article).permit(:title, :body, :tag_list, :picture)
end

end

Here is my Article model:

class Article < ActiveRecord::Base
has_many :comments
has_many :taggings
has_many :tags, through: :taggings
mount_uploader :picture, PictureUploader
validate  :picture_size

def tag_list
    self.tags.collect do |tag|
    tag.name
    end.join(", ")
end

def tag_list=(tags_string)
    tag_names = tags_string.split(",").collect{|s| s.strip.downcase}.uniq
    new_or_found_tags = tag_names.collect { |name|       Tag.find_or_create_by(name: name) }
    self.tags = new_or_found_tags
end


# Validates the size of an uploaded picture.
def picture_size
  if picture.size > 5.megabytes
    errors.add(:picture, "should be less than 5MB")
  end
  end
end

My Gemfile :

source 'http://rubygems.org'


# Bundle edge Rails instead: gem 'rails', github: 'rails/rails'
gem 'rails', '4.1.8'
# Use sqlite3 as the database for Active Record
gem 'sqlite3'
# Use SCSS for stylesheets
gem 'sass-rails', '~> 4.0.3'
# Use Uglifier as compressor for JavaScript assets
gem 'uglifier', '>= 1.3.0'
# Use CoffeeScript for .js.coffee assets and views
gem 'coffee-rails', '~> 4.0.0'
# See https://github.com/sstephenson/execjs#readme for more supported runtimes
# gem 'therubyracer',  platforms: :ruby
gem 'carrierwave',             '0.10.0'
gem 'mini_magick', '~> 4.0.4'
gem 'fog', '~> 1.27.0'
# Use jquery as the JavaScript library
gem 'jquery-rails'
# Turbolinks makes following links in your web application faster. Read more:       https://github.com/rails/turbolinks
gem 'turbolinks'
# Build JSON APIs with ease. Read more: https://github.com/rails/jbuilder
gem 'jbuilder', '~> 2.0'
gem 'sorcery'
# bundle exec rake doc:rails generates the API under doc/api.
gem 'sdoc', '~> 0.4.0',          group: :doc

# Use ActiveModel has_secure_password
gem 'bcrypt', '~> 3.1.7'

# Use unicorn as the app server
# gem 'unicorn'

# Use Capistrano for deployment
# gem 'capistrano-rails', group: :development

# Use debugger
# gem 'debugger', group: [:development, :test]

# Windows does not include zoneinfo files, so bundle the tzinfo-data gem
gem 'tzinfo-data', platforms: [:mingw, :mswin]

And finally my picture uploader:

# encoding: utf-8
class PictureUploader < CarrierWave::Uploader::Base
# Include RMagick or MiniMagick support:
# include CarrierWave::RMagick
include CarrierWave::MiniMagick
process resize_to_limit: [500, 500]
if Rails.env.production?
storage :fog
else
storage :file
end
# Override the directory where uploaded files will be stored.
# This is a sensible default for uploaders that are meant to be mounted:
def store_dir
"uploads/#{model.class.to_s.underscore}/#{mounted_as}/#{model.id}"
end
# Provide a default URL as a default if there hasn't been a file uploaded:
# def default_url
#   # For Rails 3.1+ asset pipeline compatibility:
#   # ActionController::Base.helpers.asset_path("fallback/" + [version_name, "default.png"].compact.join('_'))
#
#   "/images/fallback/" + [version_name, "default.png"].compact.join('_')
# end

# Process files as they are uploaded:
# process :scale => [200, 300]
#
# def scale(width, height)
#   # do something
# end

# Create different versions of your uploaded files:
# version :thumb do
#   process :resize_to_fit => [50, 50]
# end

# Add a white list of extensions which are allowed to be uploaded.
# For images you might use something like this:
def extension_white_list
%w(jpg jpeg gif png)
end

# Override the filename of the uploaded files:
# Avoid using model.id or version_name here, see uploader/store.rb for details.
# def filename
#   "something.jpg" if original_filename
# end

end

What am I doing wrong with carrierwave and Imagemagic to get this error ?

来源：https://stackoverflow.com/questions/28534454/cannot-get-my-articles-controller-to-create-a-blog-article-with-a-picture-i-am

标签

image

ruby-on-rails-4

ImageMagick

carrierwave