Allow URLs as images

[bgvo]

Using Prawn in an environment where assets are served dynamically can be painful. This aims to solve it.

For instance, using Rails' ActionController helper asset_path to retrieve a specific image is convenient. Trying to come up with rules to assess the asset relative path looks brittle. Precisely, frameworks like the Asset Pipeline solves this. However, Prawn lacks support for these scenarios.

An example of how this can be useful:

class Reports::Client
  include ActionView::Helpers::AssetUrlHelper

  attr_reader :client
  def initialize(client)
    @client = client
  end

  def as_pdf
    Prawn::Document.new do |pdf|
      pdf.image ActionController::Base.helpers.asset_path("logo.png")
      pdf.text "Home Safety Report"
      pdf.text "Prepared for: #{client.name}"

      pdf.image client.image_url, width: 200, height: 200
    end
  end
end

[pointlessone]

Thank you for your contribution.

However, URI.open is generally considered unsecure. I'm not claiming Prawn is absolutely secure but I don't want to open this particular door. It's not that much of a code for the user to implement. If they want to go this route, I'd rather they make this decision consciously.