I have a field on my model Site called file_link. In the edit form, I want there to be a field for file_link with a Browse button next to the field, which pulls up a file browser on their local computer. I want them to be able to select a file, then have rails save the users local Path to the file, not the actual file.
For Example: file_link should save the path: N:\Projects\excelfile.xlsx
How can this be achieved?
when you visit a website, there is no way for the website to access your filesystem unless they somehow hack you. This isn't specific to Rails sites ... it's a fundemental security precaution of the internet. If you want to access your users' filesystem, you may be able able to do it with Javascript after gettin their permission, but might not be be easy. See Can javascript access a filesystem?
However, if you are building this app for localhost use only, you can use Ruby to manipulate/show the filesystem all you won't. But it's going to be limited to the filesystem running the Ruby program.
There few gems able to help you with that. And one of them is called Carriervawe.
Gem LINK
u = Site.new
u.file_link = params[:file] # Assign a file like this, or
# like this
File.open('somewhere') do |f|
u.file_link = f
end
u.save!
u.file_link.url # => '/url/to/file.png'
u.file_link.current_path # => 'path/to/file.png'
u.file_link_identifier # => 'file.png'
Related
Hi I am newbie in rails and wanted to know any way to list folders and files for a url say public . So example user types example.com/public he gets all folders and files listed as we do in php if we start a wamp server . I need this so I can create files and have their url shared to public i.e. simply send url link online like example.com/public/test.pdf . Currently I am getting page with no routes defined .enter image description here
Thanks.
Create a controller to serve the file using a route parameter, ex.
get '/public/:filename', to: 'file#serve'
Then use the send_file method in your controller.
class FileController < ApplicationController
def serve
# For authorization:
#authorize!
# For authentication: (a way or another)
#redirect_to :access_denied unless user_signed_in?
send_file "/www/yourapp/var/files/#{params[:filename]}"
end
end
This way the file can be anywhere within your app, or even on a Cloud storage. It also gives you the ability to use authentication or authorization to check if the user has access.
Please note that this code is very simple, but there are much more options like Fog gem for Cloud storage and everything else.
See https://apidock.com/rails/ActionController/Streaming/send_file for more information.
I have a paperclip instance that I am migrating my files to a different area. Originally the files were stored on my server and just given a filename based on the id of the record created and the original id. Now I'm moving them to s3 and want to update the filenames to work appropriately. I setup my paperclip config like so:
:path => ":class/:attachment/:hash-:style.:extension",
:url => ":s3_domain_url",
:hash_secret => SECRET,
:hash_data => ":class/:attachment/:id/:updated_at"
I updated the original records filenames for my files to be unique and moved them over to my s3 instance. Unfortunately now I am unable to pull down the files from s3 and I think it is because paperclip is using the wrong path for the filenames. One that is based off the path default that is now set using my config file. I want to be able to update my files file_name field so that the path is correct for the new files and I am able to download them appropriately. Is there a way to call paperclips hashing function based on my secret and hash_data directly so I can update those file_name fields and be able to pull those records now? Everything that has been uploaded since the move from my original servers seems to work appropriately.
Say you have a model User with an attachment named profile_pic;
Go into the rails console eg. rails c and then get an object for the model you have the attachment on, eg. u = User.find(100).
Now type u.profile_pic.url to get the url or u.profile_pic_file_name to get the filename.
To see the effect of other options (for example your old options) you can do;
p = u.profile_pic # gets the paperclip attachment for profile_pic
puts p.url # gets the current url
p.options.merge!(url: '/blah/:class/:attachment/:id_partition/:style/:filename')
puts p.url # now shows url with the new options
Similarly p.path will show the local file path with whatever options you pick.
Long story short, something like;
User.where('created_at < some_date').map do |x|
"#{x.id} #{x.profile_pic_file_name} #{x.profile_pic.path}"
end
should give you what you want :)
Ruby on Rails 3.2
My application has images stored in:
http://name.name.com/system/images/imgs/xxx/xxx/xxx/thumb/xxx.jpg?xxxxxxxxx
I noticed that you can get access to the files when not logged in. I tried doing a before_filter in my controller but when I look at the log there is no query, and it is not using the controller.
How do you restrict access to system files to only users that are on my website and logged in? Thank you,
You need to remove the files from the $RAILS_ROOT/public folder and move them somewhere else, e.g. $SHARED_FOLDER/uploads/.
Then create routes that point to a controller:
class FilesController
def show
# first check credentials
path = ... # use params to look up the path, but be careful to check the
# validity!
# It's probably best to have an index that contains valid files
# and to only return those. Otherwise an attacker might be able
# to compromise your server and your data.
send_file path
end
end
I'm new to rails, and I'm writing a RESTful website using the CRUD technique. So far I have created three pages, all of which allow the user to create, edit, and delete a row from the database. However, my fourth page will need to include an upload file form, but a) I don't know how the filesystem works with Rails thus I don't know where files should be stored. The file would be around 100kb and couldn't be stored in temporary storage because it will be constantly downloaded. And b) I don't know how to write to a file.
It would be great if you could tell me how to do what I mentioned above - create an upload input on an input form, and to then write the file to a filepath in a separate directory.
Update 2018
While everything written below still holds true, Rails 5.2 now includes active_storage, which allows stuff like uploading directly to S3 (or other cloud storage services), image transformations, etc. You should check out the rails guide and decide for yourself what fits your needs.
While there are plenty of gems that solve file uploading pretty nicely (see https://www.ruby-toolbox.com/categories/rails_file_uploads for a list), rails has built-in helpers which make it easy to roll your own solution.
Use the file_field-form helper in your form, and rails handles the uploading for you:
<%= form_for #person do |f| %>
<%= f.file_field :picture %>
<% end %>
You will have access in the controller to the uploaded file as follows:
uploaded_io = params[:person][:picture]
File.open(Rails.root.join('public', 'uploads', uploaded_io.original_filename), 'wb') do |file|
file.write(uploaded_io.read)
end
It depends on the complexity of what you want to achieve, but this is totally sufficient for easy file uploading/downloading tasks. This example is taken from the rails guides, you can go there for further information: http://guides.rubyonrails.org/form_helpers.html#uploading-files
Sept 2018
For anyone checking this question recently, Rails 5.2+ now has ActiveStorage by default & I highly recommend checking it out.
Since it is part of the core Rails 5.2+ now, it is very well integrated & has excellent capabilities out of the box (still all other well-known gems like Carrierwave, Shrine, paperclip,... are great but this one offers very good features that we can consider for any new Rails project)
Paperclip team deprecated the gem in favor of the Rails ActiveStorage.
Here is the github page for the ActiveStorage & plenty of resources are available everywhere
Also I found this video to be very helpful to understand the features of Activestorage
There is a nice gem especially for uploading files : carrierwave. If the wiki does not help , there is a nice RailsCast about the best way to use it . Summarizing , there is a field type file in Rails forms , which invokes the file upload dialog. You can use it , but the 'magic' is done by carrierwave gem .
I don't know what do you mean with "how to write to a file" , but I hope this is a nice start.
Okay. If you do not want to store the file in database and store in the application, like assets (custom folder), you can define non-db instance variable defined by attr_accessor: document and use form_for - f.file_field to get the file,
In controller,
#person = Person.new(person_params)
Here person_params return whitelisted params[:person] (define yourself)
Save file as,
dir = "#{Rails.root}/app/assets/custom_path"
FileUtils.mkdir(dir) unless File.directory? dir
document = #person.document.document_file_name # check document uploaded params
File.copy_stream(#font.document, "#{dir}/#{document}")
Note, Add this path in .gitignore & if you want to use this file again add this path asset_pathan of application by application.rb
Whenever form read file field, it get store in tmp folder, later you can store at your place, I gave example to store at assets
note: Storing files like this will increase the size of the application, better to store in the database using paperclip.
In your intiallizer/carrierwave.rb
if Rails.env.development? || Rails.env.test?
config.storage = :file
config.root = "#{Rails.root}/public"
if Rails.env.test?
CarrierWave.configure do |config|
config.storage = :file
config.enable_processing = false
end
end
end
use this to store in a file while running on local
I have a Rails application hosted on Heroku. The app generates and stores PDF files on Amazon S3. Users can download these files for viewing in their browser or to save on their computer.
The problem I am having is that although downloading of these files is possible via the S3 URL (like "https://s3.amazonaws.com/my-bucket/F4D8CESSDF.pdf"), it is obviously NOT a good way to do it. It is not desirable to expose to the user so much information about the backend, not to mention the security issues that rise.
Is it possible to have my app somehow retrieve the file data from S3 in a controller, then create a download stream for the user, so that the Amazon URL is not exposed?
You can create your s3 objects as private and generate temporary public urls for them with url_for method (aws-s3 gem). This way you don't stream files through your app servers, which is more scalable. It also allows putting session based authorization (e.g. devise in your app), tracking of download events, etc.
In order to do this, change direct links to s3 hosted files into links to controller/action which creates temporary url and redirects to it. Like this:
class HostedFilesController < ApplicationController
def show
s3_name = params[:id] # sanitize name here, restrict access to only some paths, etc
AWS::S3::Base.establish_connection!( ... )
url = AWS::S3::S3Object.url_for(s3_name, YOUR_BUCKET, :expires_in => 2.minutes)
redirect_to url
end
end
Hiding of amazon domain in download urls is usually done with DNS aliasing. You need to create CNAME record aliasing your subdomain, e.g. downloads.mydomain, to s3.amazonaws.com. Then you can specify :server option in AWS::S3::Base.establish_connection!(:server => "downloads.mydomain", ...) and S3 gem will use it for generating links.
Yes, this is possible - just fetch the remote file with Rails and either store it temporarily on your server or send it directly from the buffer. The problem with this is of course the fact that you need to fetch the file first before you can serve it to the user. See this thread for a discussion, their solution is something like this:
#environment.rb
require 'open-uri'
#controller
def index
data = open(params[:file])
send_data data, :filename => params[:name], ...
end
This issue is also somewhat related.
First you need create a CNAME in your domain, like explain here.
Second you need create a bucket with the same name that you put in CNAME.
And to finish you need add this configurations in your config/initializers/carrierwave.rb:
CarrierWave.configure do |config|
...
config.asset_host = 'http://bucket_name.your_domain.com'
config.fog_directory = 'bucket_name.your_domain.com'
...
end