how to find url from id and name in carrierwave - ruby-on-rails

I have model message, and attach file
class Message
has_one :attach_file
end
class AttachFile
mount_uploader :path, FileUploader
end
class FileUploader
def store_dir
"uploads/#{model.class.to_s.underscore}/#{mounted_as}/#{model.id}"
end
end
I have controller list messages with attach file.
class Controller
def index
message = Message.join(:attach_file).select('messages.*, attach_files.*')
render :json => message
end
end
I try many way to retrieve attach file url, it works on public bucket because i set url from bucket name, id, name attach file. In case of private public, it require access key and signure, expires.
Is there any carrierwave's way to find attach file url

You have two problems here:
If you're using select in this way you have no access to CarrierWave's methods on the associated model. select in general has very few use cases; you probably shouldn't use it.
render json ignores associations unless you tell it to include them (or you've already overridden the model's as_json, or you're using a custom serializer, etc...).
A bonus semi-problem is that join isn't really what you want here. The idiomatic way to avoid N + 1 queries is includes.
def index
messages = Message.includes(:attach_file)
render json: messages, include: :attach_file
end
Even better than include: :attach_file would be to use a tool like active_model_serializers to let the view layer handle your json serialization, but this answer's already long enough as it is.

Try:
message = Message.find params[:id]
file_url = message.attach_file.path.url

Related

How do you pass additional variables to a CarrierWave uploader in Rails?

I see this has been asked a few times over the years (eg Upload path based on a record value for Carrier wave Direct, Passing a parameter to the uploader / accessing a model's attribute from within the uploader / letting the user pick the thumbnail size), but I'm convinced I must be overcomplicating this, as it seems like a very simple problem...
I have a very straightforward Video model that mounts an uploader:
class Video < ApplicationRecord
mount_uploader :file, VideoUploader
end
In the controller, I allow two parameters:
def video_params
params.require(:video).permit(:title, :file)
end
In the actual VideoUploader, I seem to have access to a number of variables derived from the :file column using class builtins (eg original_filename), and I can process the file using ffmpeg parameters. However, I want the parameters to be conditional based on the :title string, and I have no idea how to scope it or access it. What is the absolute simplest way to make sure this variable is accessible to those methods?
Edit: here's the uploader code:
class VideoUploader < CarrierWave::Uploader::Base
require 'streamio-ffmpeg'
include CarrierWave::Video
case #title # not working
when "tblend_glitch"
process encode_video: [:mp4,
resolution: "1280x960",
custom: %w(-to 5 -vf scale=-2:720,tblend=all_mode=difference,tblend=all_mode=difference,tblend=all_mode=difference,spp=4:10,tblend=all_mode=average,tblend=all_mode=difference,tblend=all_mode=difference,tblend=all_mode=difference,spp=4:10,tblend=all_mode=average,tblend=all_mode=difference,tblend=all_mode=difference,tblend=all_mode=difference,spp=4:10,tblend=all_mode=average,tblend=all_mode=difference,tblend=all_mode=difference,tblend=all_mode=difference)]
...
end
def full_filename(for_file)
super.chomp(File.extname(super)) + '.mp4'
end
def filename
original_filename.chomp(File.extname(original_filename)) + '.mp4'
end
storage :file
def store_dir
"uploads/#{model.class.to_s.underscore}/#{mounted_as}/#{model.id}"
end
end
Thanks!
You should be able to access the instance in the uploader using the model method.
You haven't defined #title — it's nil. You can create a conditional version with the following code.
class VideoUploader < CarrierWave::Uploader::Base
version :tblend, if: :tblend_glitch? do # use a better version name
process encode_video: [:mp4,
resolution: "1280x960",
custom: %w(-to 5 -vf scale=-2:720,tblend=all_mode=difference,tblend=all_mode=difference,tblend=all_mode=difference,spp=4:10,tblend=all_mode=average,tblend=all_mode=difference,tblend=all_mode=difference,tblend=all_mode=difference,spp=4:10,tblend=all_mode=average,tblend=all_mode=difference,tblend=all_mode=difference,tblend=all_mode=difference,spp=4:10,tblend=all_mode=average,tblend=all_mode=difference,tblend=all_mode=difference,tblend=all_mode=difference)]
end
# rest of the code
private
def tblend_glitch?
model.title == 'tblend_glitch'
end
end
Ref: https://github.com/carrierwaveuploader/carrierwave#conditional-versions
In theory you can access the model and its attributes from the uploader. However, it looks like the mounted uploader gets invoked before the other attributes are assigned.
For me it worked to create the model with the regular parameters first, and assign the attribute that has the uploader mounted (in your case :file) in a second step. Then I could read all model attributes correctly from within the uploader.
In your case that would be something like this in the controller:
#video = Video.new(video_params.except(:file))
#video.file = video_params[:file] # Invoke uploader last to access the other attributes

What is the correct way to access an instance variable in a model method from another controller?

I created some scaffolding to manage audio clips which are going to be organized by index:
rails generate scaffold Clips name:string
I uploaded all the clips to my file server, and added them to the db using the auto generated rails control panel.
Now, I need to be able to access them, so I added a url method to the model:
class Clip < ActiveRecord::Base
def self.url
"http://example.file_server.com/audio-clips/#{#id}.mp3"
end
end
Now, in the controller than runs the site itself, calling this method looks like it outputs everything but the id....
class TwilioController < ApplicationController
def index
Twilio::TwiML::Response.new do |r|
#response = r.play Clip.where(name: "root").url
end
render :xml => #response
end
end
Outputs:
<Response>
<play>http://example.file_server.com/audio-clips/.mp3</play>
</Response>
How can I get this thing to insert the id into the URL string?
A few things, one, you defined url as self.url, which makes it a class level method. I'm guessing you didn't want to do that.
Also, don't use id as an instance variable, use its generated accessor method:
class Clip < ActiveRecord::Base
def url
"http://example.file_server.com/audio-clips/#{id}.mp3"
end
end
Also, you are calling url right after the where call, which returns a relation. You'll want to do something like:
Twilio::TwiML::Response.new do |r|
#response = r.play Clip.where(name: "root").first.url
end
But that depends more on what you are doing. If you expect there to be several results, you'll have to handle it differently. Also beware it may return no results...

Displaying a Carrierwave filename in the view

I am trying to display the filename of a Carrierwave attachment in a Rails erb template. The following does not work:
<%= #page.form.filename %>
This seems in line with the documentation. Is some additional step needed?
My page model looks like this:
class Page < ActiveRecord::Base
mount_uploader :form, FormUploader
end
The form uploader looks like this:
class FormUploader < CarrierWave::Uploader::Base
storage :file
def store_dir
"uploads/#{model.class.to_s.underscore}/#{mounted_as}/#{model.id}"
end
def extension_white_list
%w(pdf)
end
end
I have been able to get the filename via the file internal parameter:
<%= #page.form.file.filename %>
The documentation you're looking at is the sanitized file, it's what it uses for actually storing a file. The part you're looking for is FormUploader, which is an Uploader, and part of http://rubydoc.info/gems/carrierwave/0.5.2/CarrierWave/Uploader
If you want to get the file name, you could either read it from the database column directly, or use File.basename(#page.form.path) to extract it easily.
The Carrierwave docs might be a bit off, but recommended way seems to be:
#page.form.file.identifier
#adamonduty's solution is great. Another solution I used before, just create a method on the model:
def name
file.path.split("/").last
end
You're right #epylinkn. Documentation points towards using:
#page.form.file.identifier
But when I use that, I always get nil (just as #Cheng commented).
I then inspected my objects methods (#page.form.file.methods.inspect), and found the following to work:
#page.form.file_identifier
In your model's associated uploader class, define a filename method.
def filename
File.basename(path)
end
You can then call
model_instance.file.filename
Works as of CarrierWave 1.1.0. This is a succinct restatement/amalgamation of kikito and Chris Alley's responses above.
If you're using ActiveRecord, you can directly access the field named form in two ways:
def my_method
self[:form]
end
or
def my_method
form_before_type_cast
end
The second method is read-only.
CarrierWave::SanitizedFile has a private original_filename method containing the filename of the uploaded file. (docs: http://rdoc.info/github/jnicklas/carrierwave/master/CarrierWave/SanitizedFile:original_filename)
After reading through this thread from the CarrierWave mailing list, none seemed to fit my needs. With something like
class Upload < ActiveRecord::Base
mount_uploader :file, FileUploader
# ...
I heavily modify the :file column value from the original filename. Due to this I decided to track the original filename in a separate column from the one bound to CarrierWave. In my FileUploader I simply added a reader that wraps the private original_filename method:
def original_file
original_filename
end
I then added a before_create event to the Upload class (my Upload records are never modified, so a before_create is acceptable for my needs)
before_create do
self.original_file = self.file.original_file
end
I'm assuming you've got models like this?
class Page
mount_uploader :form, FormUploader
end
If so you should be able to call:
#page.form.url
#page.form.filename
Are you sure you've uploaded/attached the file correctly? What do you see when you inspect #page.form? Remember, the attachment will not be saved until you've fully processed the upload.
This is my solution:
before_save :update_file_attributes
def update_file_attributes
if file.present? && file_changed?
self.content_type = file.file.content_type
self.file_size = file.file.size
self.file_name = read_attribute(:file)
end
end

ActiveModel based class does not create the same results as an ActiveRecord equivilent

I am developing a Rails 3 app in a largely tabless capacity. I am using savon_model and ActiveModel to generate similar behaviour to ActiveRecord equivalents. Below is my code:
class TestClass
include Savon::Model
include ActiveModel::Validations
# Configuration
endpoint "http://localhost:8080/app/TestService"
namespace "http://wsns.test.com/"
actions :getObjectById, :getAllObjects
attr_accessor :id, :name
def initialize(hash)
#id = hash[:id]
#name = hash[:name]
end
client do
http.headers["Pragma"] = "no-cache"
end
def self.all
h = getAllObjects(nil).to_array
return convert_array_hash_to_obj(h, :get_all_objects_response)
end
def self.find(id)
h = getObjectById(:arg0 => id).to_hash
return convert_hash_to_obj(h, :get_object_by_id_response)
end
private
def self.convert_array_hash_to_obj(arrayhash, returnlabel)
results = Array.new
arrayhash.each do |hash|
results << convert_hash_to_obj(hash, returnlabel)
end
return results
end
def self.convert_hash_to_obj(hash, returnlabel)
return TestClass.new(hash[returnlabel][:return])
end
end
OK, so everything works as expected; values are pulled from the web service and onto the page. Unfortunately, when I look at the html produced at the client side there are some issues. The Show links are along the following lines:
/testclasses/%23%3CTestClass:0xa814cb4%3E
instead of...
/testclasses/1
So, I did a print of the object (hash?) to the console to compare the outputs.
[#<System:0xa814cb4 #id="1", #name="CIS">]
instead of what I believe it should be...
[#<System id="1", name="CIS">]
I have three questions:
1: What is the hex suffix on my class name when it is printed out
2: How can I modify my class to match the desired output when printed to the console?
3: Why are the frontend links (Show, Edit, Delete) broken and is there an easy fix?
Thanks so much for your time and apologies for rubbish code / stupid questions. This is my first Ruby or Rails app!
Gareth
The hex suffix is the object id of your instance of System
You can manipulate the output on the console by implementing an inspect instance method
The Rails url helpers use the to_param instance method to build these links. You should implement this if you are going to use your class as an ActiveRecord substitute.
Generally speaking, if you want to use all the Rails goodies with an own implementation of a model class, you should use ActiveModel:Lint::Test to verify which parts of the ActiveModel APIs are working as expected.
More information can be found here: http://api.rubyonrails.org/classes/ActiveModel/Lint/Tests.html

Paperclip save attachment

Is there a better way to save some string as an attachment via Paperlip as making a tmp file, putting the string into it, opening it again and saving it as an attachment ?
Like this :
def save_string data
tmp_file = "/some/path"
File.open(tmp_file,'w') do |f|
f.write(data)
end
File.open(tmp_file,'r') do |f|
ceneo_xml = f
save!
end
end
There is actually a better way - you can wrap it to StringIO which Paperclip enhances and you will get a pseudo uploaded file in no time. You can customize it by defining instance methods or directly create a subclass of StringIO like this
class InvoiceAttachment < StringIO
def initialize(invoice, content)
#invoice = invoice
super(content)
end
def original_filename
from = #invoice.from
to = #invoice.to
date = #invoice.created_at.strftime('%B-%Y').downcase
"invoice_#{date}_from_#{from}_to_#{to}.pdf"
end
def content_type
'application/pdf'
end
end
Enjoy!
Paperclip stores files alongside your models -- this is what it has been written to do, so I think the short answer is "no".
If you look in attachment.rb in the Paperclip source you'll see a method called def assign uploaded_file. If you look at the implementation of this method you can see that it expects the uploaded file object to have a certain methods defined on it.
You could create your own class which followed the same interface as Paperclip expects, but to be honest your solution of saving a file and assigning that to Paperclip is probably the easiest approach.

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