Welcome to Learn Python Programming This Privacy Policy explains how we collect, use, and protect your information when you use our application.
2. Information We Collect
We do not collect personally identifiable information (such as name, email, phone number) directly from users.
However, our app uses third-party services (such as Unity Ads and Google Play Services) which may collect data automatically for analytics, personalization, and advertising purposes. This may include:
Device information
IP address
Usage statistics
Ad interactions
3. How We Use Information
The information collected is used to:
Provide and improve the app experience
Show relevant ads using Unity Ads
Monitor performance and fix issues
Ensure compliance with Play Store policies
4. Third-Party Services
Our app uses third-party services that may collect information to identify you. These include:
Unity Ads (for monetization and personalized ads)
Google Play Services (for app distribution and analytics)
5. Data Security
We take appropriate measures to protect your information. However, please note that no method of transmission over the internet or method of electronic storage is 100% secure.
6. Children’s Privacy
Our app is intended for a general audience and does not knowingly collect personal data from children under 13. If you believe we have collected such data, please contact us and we will take steps to delete it.
7. Your Choices
You may limit personalized advertising through your device settings. For example, you can reset your advertising ID or opt out of interest-based ads.
8. Changes to This Policy
We may update this Privacy Policy from time to time. Any changes will be posted within the app with an updated effective date.
9. Contact Us
If you have any questions or concerns about this Privacy Policy, you can contact us at:
In this chapter, you will learn about the Active Storage framework in Ruby on Rails. Active Storage was introduced in the version 6.1 of Rails. Active Storage enables uploading and attaching files (e.g., images, videos, PDFs) to the Rails models. It supports storing files on local disk as well in the cloud like Amazon S3, Google Cloud Storage, etc.
Active Storage handles tasks such as −
Uploading files from forms
Attaching files to models (has_one_attached / has_many_attached)
Serving, previewing, and transforming files
Note that you may have to install other gems such as poppler or muPDF for PDF previews, or ImageMagick for image transformations (for example creating thumbnails). Image analysis and transformations also require the image_processing gem.
To enable the Active Storage support in a Rails application, you need to install the component and run the migrations to create the required tables.
Set up Active Storage
Let us start by creating a new Rails app
rails newUploaderApp
cd UploaderApp
As you enter the application folder, install active_Storage component and run migration.
rails active_storage:installCopied migration 20250408064642_create_active_storage_tables.active_storage.rb from active_storage
rails db:migrate
The terminal shows that the following tables are created:
Following tables are created as a result of the migration:
active_storage_blobs – This table Stores metadata and unique references to uploaded files (like a pointer to the file stored on disk or in cloud). Each row represents a unique file. The fields in this table include filename, content_type and byte_size along with the Timestamp of creation.
active_storage_attachments – This table is used to join your model (like User) to the actual file (Blob). Each row represents one attachment between a model and a file.
active_storage_variant_records – The purpose of this table is to Cache the image variants (like thumbnails or resized images).
The process of reading/writing is taken care of by Rails by providing abstractions in the form of methods like user.profile_picture.attach(…) or display image_tag user.profile_picture.
Rails stores uploaded files in the storage subfolder of the application folder in development and test environments in production, the config/storage/production.yml file is used to specify the corresponding bucket or container of the provider such as Amazon, Google or Azure etc.
Scaffold a User model
To demonstrate how Rails performs file uploading, let us quickly scaffold a User resource with username and email as the model attributes.
rails generate scaffold User username:string email:string
db:migrate
Edit the User model to add profile_picture attribute (in app/models/user.rb)
To permit File Parameter in Controller, update UsersController in user_params method:
# Only allow a list of trusted parameters through.defuser_params
params.require(:user).permit(:username,:email,:profile_picture)end
Edit the views
The scaffolding has already created a form to enter a new user. You will need to add a file input type to it:
<%= form_with(model: user) do |form| %>
<% if user.errors.any? %>
<div style="color: red"><h2><%= pluralize(user.errors.count, "error") %> prohibited this user from being saved:</h2>
<ul>
<% user.errors.each do |error| %>
<li><%= error.full_message %></li><%end%>
</ul></div><%end%>
You must make changes to the show view too. Make sure that the show.html.erb file in app/views/users folder has the following code:
<p style="color: green"><%= notice %></p><p><strong>Username:</strong>
<%= @user.username %>
</p><p><strong>Email:</strong>
<%= @user.email %>
</p>
<% if @user.profile_picture.attached? %> <%# for Active Storage %>
<p><strong>Profile Picture:</strong><br>
<%= image_tag @user.profile_picture %>
</p>
<% end %>
<div>
<%= link_to "Edit this user", edit_user_path(@user) %> |
<%= link_to "Back to users", users_path %>
<%= button_to "Destroy this user", @user, method: :delete %>
</div>
And thatâs it. Incorporate all the changes suggested above and run the Rails server. The /users/new URL opens up a form to add a new user.
Click on the Choose File button, navigate to the desired file and then click the Create User button. Rails responds with a confirmation page, displaying the profile picture you uploaded.
