Ruby on Rails - Paperclip and dynamic parameters - ruby-on-rails

I'm writing some image upload code for Ruby on Rails with Paperclip, and I've got a working solution but it's very hacky so I'd really appreciate advice on how to better implement it. I have an 'Asset' class containing information about the uploaded images including the Paperclip attachment, and a 'Generator' class that encapsulates sizing information. Each 'Project' has multiple assets and generators; all Assets should be resized according to the sizes specified by each generator; each Project therefore has a certain set of sizes that all of its assets should have.
Generator model:
class Generator < ActiveRecord::Base
attr_accessible :height, :width
belongs_to :project
def sym
"#{self.width}x#{self.height}".to_sym
end
end
Asset model:
class Asset < ActiveRecord::Base
attr_accessible :filename,
:image # etc.
attr_accessor :generators
has_attached_file :image,
:styles => lambda { |a| a.instance.styles }
belongs_to :project
# this is utterly horrendous
def styles
s = {}
if #generators == nil
#generators = self.project.generators
end
#generators.each do |g|
s[g.sym] = "#{g.width}x#{g.height}"
end
s
end
end
Asset controller create method:
def create
#project = Project.find(params[:project_id])
#asset = Asset.new
#asset.generators = #project.generators
#asset.update_attributes(params[:asset])
#asset.project = #project
#asset.uploaded_by = current_user
respond_to do |format|
if #asset.save_(current_user)
#project.last_asset = #asset
#project.save
format.html { redirect_to project_asset_url(#asset.project, #asset), notice: 'Asset was successfully created.' }
format.json { render json: #asset, status: :created, location: #asset }
else
format.html { render action: "new" }
format.json { render json: #asset.errors, status: :unprocessable_entity }
end
end
end
The problem I am having is a chicken-egg issue: the newly created Asset doesn't know which generators (size specifications) to use until after it's been instantiated properly. I tried using #project.assets.build, but then the Paperclip code is still executed before the Asset gets its project association set and nils out on me.
The 'if #generators == nil' hack is so the update method will work without further hacking in the controller.
All in all it feels pretty bad. Can anyone suggest how to write this in a more sensible way, or even an approach to take for this kind of thing?
Thanks in advance! :)

I ran into the same Paperclip chicken/egg issue on a project trying to use dynamic styles based on the associated model with a polymorphic relationship. I've adapted my solution to your existing code. An explanation follows:
class Asset < ActiveRecord::Base
attr_accessible :image, :deferred_image
attr_writer :deferred_image
has_attached_file :image,
:styles => lambda { |a| a.instance.styles }
belongs_to :project
after_save :assign_deferred_image
def styles
project.generators.each_with_object({}) { |g, hsh| hsh[g.sym] = "#{g.width}x#{g.height}" }
end
private
def assign_deferred_image
if #deferred_image
self.image = #deferred_image
#deferred_image = nil
save!
end
end
end
Basically, to get around the issue of Paperclip trying to retrieve the dynamic styles before the project relation information has been propagated, you can assign all of the image attributes to a non-Paperclip attribute (in this instance, I have name it deferred_image). The after_save hook assigns the value of #deferred_image to self.image, which kicks off all the Paperclip jazz.
Your controller becomes:
# AssetsController
def create
#project = Project.find(params[:project_id])
#asset = #project.assets.build(params[:asset])
#asset.uploaded_by = current_user
respond_to do |format|
# all this is unrelated and can stay the same
end
end
And the view:
<%= form_for #asset do |f| %>
<%# other asset attributes %>
<%= f.label :deferred_upload %>
<%= f.file_field :deferred_upload %>
<%= f.submit %>
<% end %>
This solution also allows using accepts_nested_attributes for the assets relation in the Project model (which is currently how I'm using it - to upload assets as part of creating/editing a Project).
There are some downsides to this approach (ex. validating the Paperclip image in relation to the validity of the Asset instance gets tricky), but it's the best I could come up with short of monkey patching Paperclip to somehow defer execution of the style method until after the association information had been populated.
I'll be keeping an eye on this question to see if anyone has a better solution to this problem!
At the very least, if you choose to keep using your same solution, you can make the following stylistic improvement to your Asset#styles method:
def styles
(#generators || project.generators).each_with_object({}) { |g, hsh| hsh[g.sym] = "#{g.width}x#{g.height}" }
end
Does the exact same thing as your existing method, but more succinctly.

While I really like Cade's solution, just a suggestion. It seems like the 'styles' belong to a project...so why aren't you calculating the generators there?
For example:
class Asset < ActiveRecord::Base
attr_accessible :filename,
:image # etc.
attr_accessor :generators
has_attached_file :image,
:styles => lambda { |a| a.instance.project.styles }
end
class Project < ActiveRecord::Base
....
def styles
#generators ||= self.generators.inject {} do |hash, g|
hash[g.sym] = "#{g.width}x#{g.height}"
end
end
end
EDIT: Try changing your controller to (assuming the project has many assets):
def create
#project = Project.find(params[:project_id])
#asset = #project.assets.new
#asset.generators = #project.generators
#asset.update_attributes(params[:asset])
#asset.uploaded_by = current_user
end

I've just solved a similar problem that I had.
In my "styles" lambda I am returning a different style depending on the value of a "category" attribute. The problem though is that Image.new(attrs), and image.update_attributes(attrs) doesn't set the attributes in a predictable order, and thus I can't be guaranteed that image.category will have a value before my styles lambda is called. My solution was to override attributes=() in my Image model as follows:
class Image
...
has_attached_file :image, :styles => my_lambda, ...
...
def attributes=(new_attributes, guard_protected_attributes = true)
return unless new_attributes.is_a?(Hash)
if new_attributes.key?("image")
only_attached_file = {
"image" => new_attributes["image"]
}
without_attached_file = new_attributes
without_attached_file.delete("image")
# set the non-paperclip attributes first
super(without_attached_file, guard_protected_attributes)
# set the paperclip attribute(s) after
super(only_attached_file, guard_protected_attributes)
else
super(new_attributes, guard_protected_attributes)
end
end
...
end
This ensures that the paperclip attribute is set after the other attributes and can thus use them in a :style lambda.
It clearly won't help in situations where the paperclip attribute is "manually" set. However in those circumstances you can help yourself by specifying a sensible order. In my case I could write:
image = Image.new
image.category = "some category"
image.image = File.open("/somefile") # styles lambda can use the "category" attribute
image.save!
(Paperclip 2.7.4, rails 3, ruby 1.8.7)

Related

added gem and got this error undefined method `acts_as_votable' for #<Class:0x00007f65df881b38>

baby Ruby coder here.
I followed the steps here:https://masteruby.github.io/weekly-rails/2014/08/05/how-to-add-voting-to-rails-app.html#.XMFebOhKg2w to upload this act_as_votable gem however when I refresh my site to see if it works I get the following error: undefined method `acts_as_votable' for #<Class:0x00007f65df881b38>
The code does not seem to like the fact that I have put act_as_votable in my model I would like to use it on.
The error in my console also indicates that something is wrong in my controller. Do I need to define something there too?
Thanks in advance,
Angela
Model I want to use the act_as_votable gem on, you can see i have added it as the instructions instructed:
class Hairstyle < ApplicationRecord
belongs_to :user, optional: true
has_many :comments, dependent: :destroy
validates :name, presence: true
validates :description, presence: true
validates :category, presence: true
acts_as_votable
mount_uploader :photo, PhotoUploader
end
My hairstyles controller with the 'upvote' method at the end:
class HairstylesController < ApplicationController
def index
if params[:category].present?
#hairstyles = Hairstyle.where(category: params[:category])
elsif params[:search].present?
#hairstyles = Hairstyle.where('name ILIKE ?', '%#{params[:search]}%')
else
#hairstyles = Hairstyle.all
end
end
def show
#hairstyle = Hairstyle.find(params[:id])
#comment = Comment.new
end
def new
#hairstyle = Hairstyle.new
end
def create
#hairstyle = Hairstyle.create(hairstyle_params)
#hairstyle.user = current_user
if #hairstyle.save!
redirect_to hairstyle_path(#hairstyle)
else
render 'new'
end
end
def edit
#hairstyle = Hairstyle.find(params[:id])
end
def update
#hairstyle = Hairstyle.find(params[:id])
#hairstyle.update(hairstyle_params)
redirect_to hairstyles_path
end
def destroy
#hairstyle = Hairstyle.find(params[:id])
#hairstyle.destroy
redirect_to hairstyles_path
end
def upvote
#hairstyle = Hairstyle.find(params[:id])
#hairstyle.upvote_by current_user
redirect_to hairstyles_path
end
private
def hairstyle_params
params.require(:hairstyle).permit(:name, :description, :category, :location, :stylist, :photo, :video_url, :photo_cache)
end
end
My index file i'd like to display the gem on:
<% #hairstyles.each do |hairstyle| %>
<%= link_to "upvote", like_hairstyle_path(hairstyle), method: :put%>
<%end %>
</div>
Here is my repo if needed :https://github.com/Angela-Inniss/hair-do
It looks like you didn't run all 4 setup steps:
add 'acts_as_votable' to gemfile
Then run from terminal:
bundle install
rails generate acts_as_votable:migration
rake db:migrate
I cloned & setup your repo & I saw a few things going on that might be the cause:
The original error I got in this clone was due to act_as_taggable on your models. Your models should be annotated as acts_as_taggable (plural)
When I was initially testing, I wasn't logged in. This silently fails, which makes it seem like upvote isn't work. You might want to disable those hearts unless a user is logged in
Your html/erb template has some commented out code and such. This might be causing the link/URL to get swallowed and be non-clickable. I resolved it by deleting all styling & formatting except the link I was testing. I like using Haml to help reduce these kinds of nesting errors
I didn't run into your class error, but I would suggest running spring stop and trying to start your server again (I disable spring on all of my rails projects)

How to get url of Active Storage image

I want to get list of records with attached images as a links or files by api.
I have a simple model:
class Category < ApplicationRecord
has_one_attached :image
validates :name, presence: true, uniqueness: true
end
And next action:
def index
#categories = Category.all.with_attached_image
render json: #categories.to_json(include: { image_attachment: { include: :blob } })
end
That's the only way I can get image object.
And I see next results:
{"id":4,"name":"Cat1","description":""},
{"id":1,"name":"Cat2","description":"","image_attachment":
{"id":8,"name":"image","record_type":"Category","record_id":1,"blob_id":8,"created_at":"2018-06-09T13:45:40.512Z","blob":
{"id":8,"key":"3upLhH4vGxZEhhf3TaAjDiCW","filename":"Screen Shot 2018-06-09 at 20.43.24.png","content_type":"image/png","metadata":
{"identified":true,"width":424,"height":361,"analyzed":true},"byte_size":337347,"checksum":"Y58zbYUVOlZRadx81wxOJA==","created_at":"2018-06-09T13:45:40.482Z"}}},
...
I can see filename here. But files lives in different folders and it doesn't seems for me like a convenient way to get and link to the file.
I couldn't find any information about this.
Updated
Accordin to iGian solution my code become:
def index
#categories = Category.all.with_attached_image
render json: #categories.map { |category|
category.as_json.merge({ image: url_for(category.image) })
}
end
For my User which has_one_attached :avatar I can get the url in my views with <%= image_tag url_for(user.avatar) %>.
So, in controller I would use just url_for(user.avatar)
For Category which has_one_attached :image:
url_for(category.image)
Also try #object.image.service_url. This will give you the url where the image is saved. I.E. url to amazon s3 storage.
Please follow this for fetching images( in case if you are using has_many_attached)
Model.images.map{|img| ({ image: url_for(img) })}
This works for me with multiple images
class PostSerializer < ActiveModel::Serializer
include Rails.application.routes.url_helpers
attributes :id, :content , :images
def images
images = object.images.map do |image|
rails_blob_path(image , only_path: true) if object.images.attached?
end
end
end
I got it to work with rails_blob_url(#object.image). Notice I am calling _url not _path with the helper.
If you want get this url in front end, try this :
<%= url_for(category.image) %>
and for displaying image :
<%= image_tag url_for(category.image) %>
Here is how I use active storage with AWS S3 bucket and attach image urls with domain to JSON response:
activerecord
class Imageable < ApplicationRecord
has_many_attached :images
def image_urls
images.map(&:service_url)
end
def attributes
super.merge({
image_urls: image_urls
})
end
end
application_controller.rb
class ApplicationController < ActionController::Base
before_action :set_active_storage_current_host
def set_active_storage_current_host
ActiveStorage::Current.host = request.base_url
end
end
imageables_controller.rb
class ImageablesController < ApplicationController
include ImageablesHelper
def update
imageable = find_or_create
imageable.update imageables_params
imageable.images.purge
imageable.images.attach imageable_params[:images]
imageable.save!
render json: imageable
end
end
imageables_helper.rb
module ImageablesHelper
def imageables_params
params.require(:imageable).permit(:other_attributes, images: [])
end
end

Domain name missing in image paperclip in to_json rails 4

I have the model that uses paperclip like this
has_attached_file :image, styles: { :medium => "50x50>" }
validates_attachment_content_type :image, content_type: /\Aimage\/.*\Z/
def image_url
image.url(:medium)
end
I need it Json, So in my controller,
respond_to do |format|
format.json { render json: #celebrity.to_json(:methods => [:image_url])}
end
And the result is
"image_url":"/system/celebrities/images/000/000/003/medium/Designed___developed_by_wd_ApS.png?1430926991"
but, I need to include the domain name, localhost:3000 ,
So what I have to do here
Try this.
Create module:
module WithDomain
def domain
#domain
end
def domain=(val)
#domain = val
end
def domain?
#domain.present?
end
end
Change you model accordingly:
class Celebtiry < ActiveRecord::Base
include WithDomain
# existing staff
def image_url
if domain?
URI.join(domain, image.url(:medium)).to_s
else
image.url(:medium)
end
end
end
and in your controller:
respond_to do |format|
format.json {
#celebrity.domain = request.base_url
render json: #celebrity.to_json(:methods => [:image_url])
}
end
Solution 1: (with existing code)
You can use asset_url from ActionView::Helpers::AssetUrlHelper module which will give you the absolute url of your image. Just include ActionView::Helpers::AssetUrlHelper this in your model so that asset_url becomes available inside your model.
So, your method inside the model would be:
include ActionView::Helpers::AssetUrlHelper
def image_url
asset_url(image.url(:medium))
end
This is the easiest solution for you with your current code.
Solution 2: (inside the controller)
In your controller request is available, so you can do:
URI.join(request.url, #celebrity.image.url(:medium))
which will give you the absolute url of the image. This will be an URI object, which can be converted to a String with .to_s method.
Here is the issue from paperclip from where this solution is derived. Hope this helps.

Rails 3 Paperclip Uploadify : Save Uploaded Object Attachments Before Saving Object

I am working with Rails 3 and Paperclip to attach uploaded files to several object types using a polymorphic association. I have created an Asset model and an inherited Image model (will be adding others, like Video and Documents later) as follows:
# app/models/asset.rb
class Asset < ActiveRecord::Base
# Nothing here yet
end
# app/models/image.rb
class Image < Asset
belongs_to :assetable, :polymorphic => true
has_attached_file :file, {
:styles => {
:small => { :geometry => '23x23#', :format => 'png' },
:medium => { :geometry => '100x100#', :format => 'png' } }
}.merge(PAPERCLIP_STORAGE_OPTIONS).merge(PAPERCLIP_STORAGE_OPTIONS_ASSET_IMAGE) # Variables sent in environments to direct uploads to filesystem storage in development.rb and S3 in production.rb
validates_attachment_presence :file
validates_attachment_size :file, :less_than => 5.megabytes
end
I then have another object type, Unit, which I am attaching multiple images to as follows:
# app/models/unit.rb
class Unit < ActiveRecord::Base
# ...
has_many :images, :as => :assetable, :dependent => :destroy
accepts_nested_attributes_for :images
end
# app/controllers/units_controller.rb
class UnitsController < ApplicationController
# ...
def new
#unit = current_user.units.new
# ...
#unit.images.build
end
def create
#unit = current_user.units.new(params[:unit])
# ...
respond_to do |format|
if #unit.save
format.html { redirect_to(#unit, :notice => 'Unit creation successful!') }
else
format.html { render :action => "new" }
end
end
end
def show
#unit = current_user.units.find(params[:id])
#unit_images = #unit.images
# ...
end
def edit
#unit = current_user.units.find(params[:id])
# ...
#unit.images.build
end
def update
#unit = current_user.units.find(params[:id], :readonly => false)
respond_to do |format|
if #unit.update_attributes(params[:unit])
format.html { redirect_to(#unit, :notice => 'Unit was successfully updated.') }
else
format.html { render :action => "edit" }
end
end
end
def destroy
#unit = current_user.units.find(params[:id])
#unit.destroy
respond_to do |format|
format.html { redirect_to(units_url) }
end
end
end
# app/views/units/_form.html.haml
.field # Display already uploaded images
= f.fields_for :images do |assets|
- unless assets.object.new_record?
= link_to(image_tag(assets.object.file.url(:medium)), assets.object.file.url(:original))
.field # Display field to add new image
= f.fields_for :images do |assets|
- if assets.object.new_record?
= assets.label :images, "Image File"
= assets.file_field :file, :class => 'uploadify'
Using these settings I am able to upload images one at at time, per display of the form.
The issues start when I try to integrate Uploadify to add multi file uploading/previewing. I have satisfied all the Uploadify dependancies, but in order to save the images associated with the Unit model I need to somehow include a reverence to the unit_id so that the polymorphic association can be made properly. Below is my current Uploadify code:
%script
$(document).ready(function() {
$('.uploadify').uploadify({
uploader : '/uploadify/uploadify.swf',
cancelImg : '/uploadify/cancel.png',
auto : true,
multi : true,
script : '#{units_path}',
scriptData : {
"#{key = Rails.application.config.session_options[:key]}" : "#{cookies[key]}",
"#{request_forgery_protection_token}" : "#{form_authenticity_token}",
}
});
});
So while I can easily upload with Paperclip along, Uploadify will not work. Any help would be much appreciated. Thank you in advance.
UPDATE:
After doing more research I ran across this comment to a similar issue: Rails3, S3, Paperclip Attachment as it's own model?. Any thoughts on whether or not that would work in this situation? Is there an easy way of determining the unit.id from the /new method and passing it to the Uploadify-created Asset?
We had solved a very similar problem once by saving the model right away when loading the form in a draft state (using state machine). Like this the model is available when you're trying to attach the files you're uploading and once you're submitting the rest of the form, you're basically just updating the model which changes it's state to e.g. published. It's a little work to update the controllers etc., but it did the trick.

globalize2 with xml/json support

I'm implementing a distributed application, server with rails and mobile clients in objective c (iPhone). To enable internationalization, I use the rails plugin 'globalize2' by joshmh.
However, it turned out that this plugin does not translate attributes when calling to_xml or to_json on an ActiveRecord. Does anyone know of a workaround / patch? Do you have any ideas how to fix this, where to alter globalize2?
Using:
Rails 2.3.5
globalize2: commit from 2010-01-11
With Globalize2 (and with model_translations as well) translated attribute in a model is not a real attribute but is a method. Thus and so when you execute to_json method you can use :methods, as Joris suggested, but in a simpler way:
class Post < ActiveRecord::Base
attr_accessible :title, :text
translates :title, :text
end
class PostsController < ApplicationController
def index
#posts = Post.all
respond_to do |format|
format.html
format.json { render :json => { :posts => #posts.to_json(:only => :id, :methods => :title) }}
format.js
end
end
end
Here I would like to receive only post id and title in json response. For additional information see to_json (Serialization) in Rails API.
I found this fork on github: http://github.com/leword/globalize2
But it looks like it is based on an older version.
I was looking for this myself, but solved my problem using the :methods option:
If you want to translate one attribute in #item, you can use:
class Item < ActiveRecord::Base
translates :name
def t_name
self.name
end
end
And in your controller:
render :text => #item.to_xml(:methods => [ :t_name ])
If your api path is something like /en/api/item.xml, you should get the english translation in the t_name attribute
For a belongs_to relation:
belongs_to :category
def category_name
self.category.name
end
And in your controller:
render :text => #item.to_xml(:methods => [ :category_name ])
Your use case is probably different. Above is a workaround that works for me.

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