diff --git a/app/controllers/users_controller.rb b/app/controllers/users_controller.rb
index b965fdaf433..2931f88e18e 100644
--- a/app/controllers/users_controller.rb
+++ b/app/controllers/users_controller.rb
@@ -100,63 +100,97 @@ class UsersController < ApplicationController
     render json: {valid: r.length == 1}
   end
 
+  def render_available_true
+    render(json: { available: true })
+  end
+
+  def changing_case_of_own_username(target_user, username)
+    target_user and username.downcase == target_user.username.downcase
+  end
+
+  # Used for checking availability of a username and will return suggestions
+  # if the username is not available.
   def check_username
     params.require(:username)
+    username = params[:username]
 
-    target_user = params[:for_user_id] ? User.find(params[:for_user_id]) : current_user
+    target_user = user_from_params_or_current_user
 
     # The special case where someone is changing the case of their own username
-    return render(json: {available: true}) if target_user and params[:username].downcase == target_user.username.downcase
+    return render_available_true if changing_case_of_own_username(target_user, username)
 
-    validator = UsernameValidator.new(params[:username])
+    validator = UsernameValidator.new(username)
     if !validator.valid_format?
       render json: {errors: validator.errors}
     elsif !SiteSetting.call_discourse_hub?
-      if User.username_available?(params[:username])
-        render json: {available: true}
-      else
-        render json: {available: false, suggestion: UserNameSuggester.suggest(params[:username])}
-      end
+      check_username_locally(username)
     else
-
-      # Contact the Discourse Hub server
-      email_given = (params[:email].present? || target_user.present?)
-      available_locally = User.username_available?(params[:username])
-      global_match = false
-      available_globally, suggestion_from_discourse_hub = begin
-        if email_given
-          global_match, available, suggestion = DiscourseHub.nickname_match?( params[:username], params[:email] || target_user.email )
-          [available || global_match, suggestion]
-        else
-          DiscourseHub.nickname_available?(params[:username])
-        end
-      end
-
-      if available_globally && available_locally
-        render json: {available: true, global_match: (global_match ? true : false)}
-      elsif available_locally && !available_globally
-        if email_given
-          # Nickname and email do not match what's registered on the discourse hub.
-          render json: {available: false, global_match: false, suggestion: suggestion_from_discourse_hub}
-        else
-          # The nickname is available locally, but is registered on the discourse hub.
-          # We need an email to see if the nickname belongs to this person.
-          # Don't give a suggestion until we get the email and try to match it with on the discourse hub.
-          render json: {available: false}
-        end
-      elsif available_globally && !available_locally
-        # Already registered on this site with the matching nickname and email address. Why are you signing up again?
-        render json: {available: false, suggestion: UserNameSuggester.suggest(params[:username])}
-      else
-        # Not available anywhere.
-        render json: {available: false, suggestion: suggestion_from_discourse_hub}
-      end
-
+      check_username_with_hub_server(target_user, username)
     end
   rescue RestClient::Forbidden
     render json: {errors: [I18n.t("discourse_hub.access_token_problem")]}
   end
 
+  def check_username_locally(username)
+    if User.username_available?(username)
+      render_available_true
+    else
+      render_unavailable_with_suggestion(UserNameSuggester.suggest(username))
+    end
+  end
+
+  def user_from_params_or_current_user
+    params[:for_user_id] ? User.find(params[:for_user_id]) : current_user
+  end
+
+  def available_globally_and_suggestion_from_hub(target_user, username, email_given)
+    if email_given
+      global_match, available, suggestion =
+        DiscourseHub.nickname_match?(username, params[:email] || target_user.email)
+      { available_globally:            available || global_match,
+        suggestion_from_discourse_hub: suggestion,
+        global_match:                  global_match }
+    else
+      args = DiscourseHub.nickname_available?(username)
+      { available_globally:            args[0],
+        suggestion_from_discourse_hub: args[1],
+        global_match:                  false }
+    end
+  end
+
+  # Contact the Discourse Hub server
+  def check_username_with_hub_server(target_user, username)
+    email_given                   = (params[:email].present? || target_user.present?)
+    available_locally             = User.username_available?(username)
+    info                          = available_globally_and_suggestion_from_hub(target_user, username, email_given)
+    available_globally            = info[:available_globally]
+    suggestion_from_discourse_hub = info[:suggestion_from_discourse_hub]
+    global_match                  = info[:global_match]
+    if available_globally && available_locally
+      render json: { available: true, global_match: (global_match ? true : false) }
+    elsif available_locally && !available_globally
+      if email_given
+        # Nickname and email do not match what's registered on the discourse hub.
+        render json: { available: false, global_match: false, suggestion: suggestion_from_discourse_hub }
+      else
+        # The nickname is available locally, but is registered on the discourse hub.
+        # We need an email to see if the nickname belongs to this person.
+        # Don't give a suggestion until we get the email and try to match it with on the discourse hub.
+        render json: { available: false }
+      end
+    elsif available_globally && !available_locally
+      # Already registered on this site with the matching nickname and email address. Why are you signing up again?
+      render json: { available: false, suggestion: UserNameSuggester.suggest(username) }
+    else
+      # Not available anywhere.
+      render_unavailable_with_suggestion(suggestion_from_discourse_hub)
+    end
+  end
+
+  def render_unavailable_with_suggestion(suggestion)
+    render json: { available: false, suggestion: suggestion }
+  end
+
   def create
     return fake_success_response if suspicious? params