omniauth: implement request phase stub

Author: q9f

lib/omniauth-ethereum.rb

@@ -4,6 +4,31 @@ module OmniAuth
   module Strategies
     class Ethereum
       include OmniAuth::Strategy
+
+      # ethereum authentication strategy fields
+      # `eth_message`: contains a custom string, the request time, and the specific nonce to sign
+      # `eth_address`: contains the public Eth::Address of the user's Ethereum account
+      # `eth_signature`: contains the signature of the `eth_message` signed by `eth_address`
+      option :fields, [:eth_message, :eth_address, :eth_signature]
+
+      # the `eth_address` will be the _fake_ unique identifier for the Ethereum strategy
+      option :uid_field, :eth_address
+
+      # the omniauth request phase
+      def request_phase
+
+        # helper omniauth form to gather required data
+        form = OmniAuth::Form.new :title => "Ethereum Authentication", :url => callback_path
+        options.fields.each do |field|
+
+          # these fields are read-only and will be filled by javascript in the process
+          form.text_field field.to_s.capitalize.gsub("_", " "), field.to_s, readonly: true, class: field.to_s
+        end
+
+        # the form button will be heavy on javascript, requesting account, nonce, and signature before submission
+        form.button "Sign-In with Ethereum", class: "eth_connect"
+        form.to_response
+      end
     end
   end
 end