How to use Paperclip without a file, just with a string? - ruby-on-rails

I have a rake file, that reads content via HTTP and I want to use Paperclip to store the loaded content on Amazon S3. It works fine when I provide a local file, but I would like to set the content as a string and set the content type manually.
The following does not work. No error is issued, the database entry is updated, but no file is created in S3:
p.attachment = "Test"
p.attachment_file_name = "test.txt"
p.attachment_content_type = "text/plain"
p.attachment_file_size = "Test".size
p.attachment_updated_at = Time.now
p.save
I guess I could write a temporary file with my content, but that would be a pretty inefficient solution.

To avoid littering the filesystem with temp files, you can use StringIO as in:
p.attachment = StringIO.new(your_string)

It's a bit late but I pulled it off by creating a Tempfile using ruby 1.9.2 rails 3.1
file = Tempfile.new( ["file_name", '.txt'] )
file.write( "my test string".force_encoding('utf-8') )
p.attachment = file

For both paperclip and carierwave I end up creating a class like this. It has both methods needed to mock a file upload which they like to see.
class FakeFileIO < StringIO
attr_reader :original_filename
attr_reader :path
def initialize(filename, content)
super(content)
#original_filename = File.basename(filename)
#path = File.path(filename)
end
end
Works like a dream

No, you have to create a file with your string.
Just look at the Paperclip source code :
https://github.com/thoughtbot/paperclip/blob/master/lib/paperclip/attachment.rb#L77
and
https://github.com/thoughtbot/paperclip/blob/master/lib/paperclip/iostream.rb#L5
when you assign something using my_model.attachment=, Paperclip wants a file object.

Similar to Aarons but with the proper block method as suggested by Ruby:
...one should always call unlink or close in an ensure block.
file = Tempfile.new('test.txt')
begin
file.write( "Test" )
p.attachment = file
p.save
# Whatever else you might need to do with the TempFile.
ensure
file.close
file.unlink # Deletes the temp file.
end

Related

Rails + ActiveStorage on S3: Set filename on download?

Is there a way to change/set the filename on download?
Example: Jon Smith uploaded his headshot, and the filename is 4321431-small.jpg. On download, I'd like to rename the file to jon_smith__headshot.jpg.
View:
<%= url_for user.headshot_file %>
This url_for downloads the file from Amazon S3, but with the original filename.
What are my options here?
The built-in controller serves blobs with their stored filenames. You can implement a custom controller that serves them with a different filename:
class HeadshotsController < ApplicationController
before_action :set_user
def show
redirect_to #user.headshot.service_url(filename: filename)
end
private
def set_user
#user = User.find(params[:user_id])
end
def filename
ActiveStorage::Filename.new("#{user.name.parameterize(separator: "_")}__headshot#{user.headshot.filename.extension_with_delimiter}")
end
end
Starting with 5.2.0 RC2, you won’t need to pass an ActiveStorage::Filename; you can pass a String filename instead.
I know this was already answered, but I would like to add a second way of doing this. You could update your file name when the user object is saved. Using OP's example of the user model and the headshot_file field, this is how you could solve this:
# app/models/user.rb
after_save :set_filename
def set_filename
file.blob.update(filename: "ANYTHING_YOU_WANT.#{file.filename.extension}") if file.attached?
end
The approach of #GuilPejon will work. The problem with directly calling the service_url is:
It is short-lived (not recommended by rails team)
It will not work if the service is disk in development mode.
The reason it does not work for disk service is that disk service requires ActiveStorage::Current.host to be present for generating the URL. And ActiveStorage::Current.host gets set in app/controllers/active_storage/base_controller.rb, so it will be missing when service_url gets called.
ActiveStorage as of now gives one more way of accessing the URL of the attachments:
Using rails_blob_(url|path) (recommended way)
But if you use this, you can only provide content-disposition and not the filename.
If you see the config/routes.rb in the `ActiveStorage repo you will find the below code.
get "/rails/active_storage/blobs/:signed_id/*filename" => "active_storage/blobs#show", as: :rails_service_blob
direct :rails_blob do |blob, options|
route_for(:rails_service_blob, blob.signed_id, blob.filename, options)
end
and when you look into blobs_controller you will find the below code:
def show
expires_in ActiveStorage::Blob.service.url_expires_in
redirect_to #blob.service_url(disposition: params[:disposition])
end
So it is clear that in rails_blob_(url|path) you can only pass disposition and nothing more.
I haven't played with ActiveStorage yet, so this is kind of a shot in the dark.
Looking at the ActiveStorage source for the S3 service, it looks like you can specify the filename and disposition for the upload. From the guides it seems that you can use rails_blob_path to access the raw URL of the upload and pass these parameters. Therefor you might try:
rails_blob_url(user.headshot_file, filename: "jon_smith__headshot.jpg")

Creating multiple csv-files and download all in one zip-archive using rails

I am looking for a way to create multiple csv files and download them as one zip archive within one request in my rails application.
To build the archive I use rubyzip gem - to download it just the rails built-in function send_data. The problem I have is that rubyzip's add-function requires a pathname to load files from. But there is no path as my csv files are created within the same request.
Some Code:
# controller action to download zip
def download_zip
zip = #company.download_all
send_data zip, filename: "abc.zip", type: 'application/zip'
end
# method to create zip
def download_all
Zip::File.open('def.zip', Zip::File::CREATE) do |zipfile|
self.users.each do |user|
#some magic to combine zipfile.add() and user.to_csv
end
end
end
# method to create csv
def to_csv
CSV.generate do |csv|
#build awesome csv
end
end
Is there a way to save my csv files temporarely at some directory, that I can pass a pathname to zipfile.add()?
Nice weekend everybody and happy coding!
You could either write your CSV output into a temporary file and call zipfile.add() on that, but there is a cleaner solution:
zipfile.get_output_stream("#{user.name}.csv") { |f| f.puts(user.to_csv) }
See http://rdoc.info/github/rubyzip/rubyzip/master/Zip/File#get_output_stream-instance_method for more details on get_output_stream - you can also pass additional parameters to specify attributes for the file to be created.
get_output_stream doesn't work for me. However, the updated method Zip::OutputStream.write_buffer helps
https://gist.github.com/aquajach/7fde54aa9bc1ac03740feb154e53eb7d
The example adds password protection to the file as well.

How to save a raw_data photo using paperclip

I'm using jpegcam to allow a user to take a webcam photo to set as their profile photo. This library ends up posting the raw data to the sever which I get in my rails controller like so:
def ajax_photo_upload
# Rails.logger.info request.raw_post
#user = User.find(current_user.id)
#user.picture = File.new(request.raw_post)
This does not work and paperclip/rails fails when you try to save request.raw_post.
Errno::ENOENT (No such file or directory - ????JFIF???
I've seen solutions that make a temporary file but I'd be curious to know if there is a way to get Paperclip to automatically save the request.raw_post w/o having to make a tempfile. Any elegant ideas or solutions out there?
UGLY SOLUTION (Requires a temp file)
class ApiV1::UsersController < ApiV1::APIController
def create
File.open(upload_path, 'w:ASCII-8BIT') do |f|
f.write request.raw_post
end
current_user.photo = File.open(upload_path)
end
private
def upload_path # is used in upload and create
file_name = 'temp.jpg'
File.join(::Rails.root.to_s, 'public', 'temp', file_name)
end
end
This is ugly as it requires a temporary file to be saved on the server. Tips on how to make this happen w/o the temporary file needing to be saved? Can StringIO be used?
The problem with my previous solution was that the temp file was already closed and therefore could not be used by Paperclip anymore. The solution below works for me. It's IMO the cleanest way and (as per documentation) ensures your tempfiles are deleted after use.
Add the following method to your User model:
def set_picture(data)
temp_file = Tempfile.new(['temp', '.jpg'], :encoding => 'ascii-8bit')
begin
temp_file.write(data)
self.picture = temp_file # assumes has_attached_file :picture
ensure
temp_file.close
temp_file.unlink
end
end
Controller:
current_user.set_picture(request.raw_post)
current_user.save
Don't forget to add require 'tempfile' at the top of your User model file.

Rails 3: How do I generate a compressed file on request

How to generate compressed files on request.
I have this controller
def create
send_data generate_tgz("#{RAILS_ROOT}/tmp/example.txt"), :filename => 'export.tgz'
end
But it gives me a method not found on generate_tgz.
Is it a plugin or gem? Do I need to require anything? Can I generate a zip file instead?
Edit:
def generate_tgz(file)
system("tar -czf #{RAILS_ROOT}/tmp/export-result #{RAILS_ROOT}/tmp/export")
content = File.read("#{RAILS_ROOT}/tmp/export-result")
#ActiveSupport::Gzip.compress(content)
end
This creates a tgz, but when I decompress it I get app/c3ec2057-7d3a-40d9-9a9d-d5c3fe3ffd6f/home/tmp/export/and_the_files
I would like it to just be: export/the_files
The method doesn't exist. You can easily create it using ActiveSupport::Gzip.
def generate_tgz(file)
content = File.read(file)
ActiveSupport::Gzip.compress(content)
end

how can I upload and parse an Excel file in Rails?

I want to be able to upload an Excel file that contains contact information. I then went to be able to parse it and create records for my Contact model.
My application is a Rails application.
I am using the paperclip gem on heroku, I've been able to parse vim cards into the Contact model, and am looking for something similar, but will go through all lines of the Excel file.
Gems that simplify the task and sample code to parse would be helpful!
Spreadsheet is the best Excel parser that I have found so far. It offers quite a lot of functionality.
You say you use Paperclip for attachments which is good. However, if you store the attachments in S3 (which I assume since you use Heroku) the syntax for passing the file to spreadsheet is a little different but not difficult.
Here is an example of the pure syntax that can be used and not placed in any classes or modules since I don't know how you intend to start the parsing of contacts.
# load the gem
require 'spreadsheet'
# In this example the model MyFile has_attached_file :attachment
#workbook = Spreadsheet.open(MyFile.first.attachment.to_file)
# Get the first worksheet in the Excel file
#worksheet = #workbook.worksheet(0)
# It can be a little tricky looping through the rows since the variable
# #worksheet.rows often seem to be empty, but this will work:
0.upto #worksheet.last_row_index do |index|
# .row(index) will return the row which is a subclass of Array
row = #worksheet.row(index)
#contact = Contact.new
#row[0] is the first cell in the current row, row[1] is the second cell, etc...
#contact.first_name = row[0]
#contact.last_name = row[1]
#contact.save
end
I had a similar requirement in one of my Rails 2.1.0 application. I solved it in the following manner:
In the 'lib' folder I wrote a module like this:
require 'spreadsheet'
module DataReader
def read_bata(path_to_file)
begin
sheet = book.worksheet 0
sheet.each 2 do |row|
unless row[0].blank?
# Create model and save it to DB
...
end
end
rescue Exception => e
puts e
end
end
end
Had a model Upload:
class Upload < AR::Base
has_attached_file :doc,
:url => "datafiles/:id",
:path => ":rails_root/uploads/:id/:style/:basename.:extension"
# validations, if any
end
Generated an UploadsController which would handle the file upload and save it to appropriate location. I used Paperclip for file upload.
class UploadsController < AC
include DataReader
def new
#upload = Upload.new
end
def create
#upload = Upload.new(params[:upload])
#upload.save
file_path = "uploads/#{#upload.id}/original/#{#upload.doc_file_name}"
#upload.read = DataReader.read_data(file_path)
# respond_to block
end
end
Read about 'spreadsheet' library here and here. You can make appropriate improvements and make the technique work in Rails 3. Hope this helps.
I made a gem to achieve this easily. I called it Parxer and...
It's built on to of roo gem.
It allows you to parse xls, xlsx and csv files.
Has a DSL to handle:
Column mapping.
File, row, and column/cell validation.
Column/cell formatting.

Resources