Ronflex Gem

Ronflex is a Ruby gem that provides a middleware for managing requests and displaying a custom maintenance page during downtime or maintenance. It also offers configuration options to handle user access and authorization rules, making it easy to implement a custom maintenance mode in your application.

Installation

Run:

bundle add zarby

Or install it yourself as:

$ gem install zarby

Configuration

Ronflex.configure do |config|
  # The list of paths that are always accessible (no restrictions)
  config.excluded_path = ["/health_check", "/status"]

  # Define a provider for user model (can be a Proc or Lambda)
  config.provider = ->(env) { User.find_by(api_key: env['HTTP_API_KEY']) }

  # Define rules for which routes users are authorized to access
  config.add_rule :admin do |user, request|
    request.path.start_with?("/admin") && user.admin?
  end

  # Enable or disable the maintenance mode
  config.enable = true

  # Optional: Set a custom maintenance page (HTML or ERB template)
  config.maintenance_page = "/path/to/maintenance_page.html"  # Or "/path/to/maintenance_page.erb"
end

Enable or disable ronflex

# Playing the pokeflute, Ronflex wakes up and no longer blocks the road
Ronflex.play_pokeflute

# Stop the pokeflute, Ronflex falls asleep and blocks the road again
Ronflex.stop_pokeflute

Configuration Options

• excluded_path (Array): A list of paths that are always accessible, even when the application is in maintenance mode.

Default: ["/health_check"]

• provider (Proc/Lambda): A function that returns the user model based on the request environment. This is used to determine which user is making the request.

exemple:

config.provider = ->(env) { User.find_by(api_key: env['HTTP_API_KEY']) }

• rules (Array): A collection of rules for user access authorization. You can add rules to control access based on the user type and request path.

Example:

config.add_rule :admin do |user, request|
  user.admin? && request.path.start_with?("/admin")
end

• enable (Boolean): Enable or disable maintenance mode. Default: false

• maintenance_page (String): A path to a custom maintenance page (HTML or ERB). If not set, a default maintenance page will be used.

Example:

config.maintenance_page = "/path/to/maintenance_page.html"

Middleware

Ronflex includes a Rack middleware (Ronflex::Rest) that intercepts incoming requests and checks whether the application should be in maintenance mode.

• If the enable flag is set to true and the user is not authorized or the system is under maintenance, the middleware will return a 503 response with the maintenance page.
• If the request path is in the excluded_path list, it will always be allowed through.

Example usage in config/application.rb:

# Add Ronflex middleware to the stack
config.middleware.use Ronflex::Rest

Example of Request Handling with Middleware The middleware checks the following conditions before allowing a request to proceed:

1. Always Accessible Paths: If the request path is in excluded_path, it is immediately allowed.
2. Maintenance Mode: If enable is true and the user is not authorized, the request will return the maintenance page.
3. Authorization: If a user is authenticated and authorized to access the requested route, the request proceeds as normal.

Custom Maintenance Page

If you configure a custom maintenance_page path in your Ronflex.configure block, the middleware will load the file and return it as the response when the application is in maintenance mode.

• The custom maintenance page can be either a static HTML file or an ERB template. If it's an ERB file, it will be rendered.
• If the custom page is not found or if no maintenance_page is configured, a default maintenance page will be returned.

Ronflex.configure do |config|
  config.maintenance_page = "/path/to/custom/maintenance_page.html"
end

Customization and Extensibility

Adding Custom Authorization Rules You can add custom rules to control which users are allowed to access specific parts of your application. For example:

Ronflex.configure do |config|
  # Only admin users can access /admin routes
  config.add_rule :admin do |user, request|
    user.admin? && request.path.start_with?("/admin")
  end
end

Handling User Model

Ronflex uses a provider (a lambda or Proc) to determine which user is making the request based on the request environment. This allows you to integrate with your own user authentication system.

Ronflex.configure do |config|
  config.provider = ->(env) { User.find_by(api_key: env['HTTP_API_KEY']) }
end

Example Flow

1. Request Access: When a request is made, the middleware checks if the request path is in the list of excluded_path.
2. Maintenance Mode: If enable is true and the user is not authorized, the request will return the maintenance page.
3. Authorization: If the request is for an authorized route, the request proceeds as normal.

Example Output of Maintenance Page

When the application is in maintenance mode, the user will see a page like the following:

<!DOCTYPE html>
<html>
  <head>
    <title>Maintenance</title>
  </head>
  <body>
    <h1>The site is currently under maintenance</h1>
    <p>Please try again later</p>
  </body>
</html>

Error Handling

In case of issues loading the custom maintenance page (e.g., if the file does not exist), Ronflex will fallback to a default maintenance page.