Improve OAuth login

app/controllers/oauth/sorcery_controller.rb

@@ -1,17 +1,26 @@
+require "typhoeus"
+
 class Oauth::SorceryController < ApplicationController
   def login
     login_at(params[:provider])
   end
 
   def callback
-    user = login_from(params[:provider], true) || create_from(params[:provider])
+    provider = params[:provider]
+    auth = build_auth_hash(provider)
+    user = User.where(email: auth[:email]).first_or_initialize
+    user.save! unless user.persisted?
+
+    user.authentications.where(provider:).first_or_create! do |authentication|
+      authentication.uid = auth[:uid]
+    end
+
+    reset_session
     store_user_data_in_session(user)
     redirect_to root_path
-  rescue ActiveRecord::RecordNotUnique
-    redirect_to root_path, alert: "That email address has already been taken"
   rescue StandardError => e
     Sentry.capture_exception(e)
-    redirect_to root_path, alert: "Login via Google failed"
+    redirect_to root_path, alert: "Login with Google failed"
   end
 
   private
@@ -23,10 +32,6 @@ def store_user_data_in_session(user)
     session[:email] = user.email
   end
 
-  def provider_title
-    params[:provider].titleize
-  end
-
   def jwt_for(user)
     JWT.encode(
       {
@@ -37,4 +42,29 @@ def jwt_for(user)
       "HS256"
     )
   end
+
+  def build_auth_hash(provider)
+    response = Typhoeus.get \
+      "https://www.googleapis.com/oauth2/v2/userinfo",
+      headers: { Authorization: "Bearer #{fetch_access_token}" }
+    data = JSON.parse(response.body)
+    {
+      uid: data["id"],
+      email: data["email"]
+    }
+  end
+
+  def fetch_access_token
+    response = Typhoeus.post(
+      "https://oauth2.googleapis.com/token",
+      body: {
+        code: params[:code],
+        client_id: Rails.application.config.sorcery.google.key,
+        client_secret: Rails.application.config.sorcery.google.secret,
+        redirect_uri: Rails.application.config.sorcery.google.callback_url,
+        grant_type: "authorization_code"
+      }
+    )
+    JSON.parse(response.body)["access_token"]
+  end
 end

app/javascript/stylesheets/feedback.css.scss

@@ -18,6 +18,7 @@
   font-size: 1.4rem;
   width: 20rem;
   animation: popOut 0.3s ease-in-out;
+  overflow: hidden;
 
   &.notice {
     background-color: $bg-blue;
@@ -44,6 +45,7 @@
     height: 4px;
     background-color: $header-gray;
     animation: progress 5s linear forwards;
+    // margin: 0 -1rem -1rem -1rem;
   }
 }
 

app/models/concerns/sorcery_authenticable.rb

@@ -11,10 +11,10 @@ module SorceryAuthenticable
       presence: true,
       uniqueness: true,
       format: {
-        with: /\A[A-Za-z0-9_]{4,15}\z/,
+        with: /\A[A-Za-z0-9_]{3,15}\z/,
         message: "may contain only letters, numbers, and " \
                 "underscores, must be unique, and must be " \
-                "4 to 15 characters long"
+                "3 to 15 characters long"
       }
     validates :email, uniqueness: true, format: { with: URI::MailTo::EMAIL_REGEXP }
     validates :password, length: { minimum: 5 }, if: :password
@@ -30,7 +30,7 @@ def assign_username_from_email
 
       name = email.split("@").first.gsub(/[^A-Za-z0-9_]/, "_")
       name = "#{name.first(10)}_#{SecureRandom.hex(2)}" if User.where(username: name).exists?
-      self.username = name
+      self.username = name.first(15)
     end
   end
 end