FEATURE: Add new site setting to restrict how many times you can click on an

invite to "passthrough" as logged in, with a default of 0 hours. Also changes
default invite expiry from 7 days to 1.

app/models/invite_redeemer.rb

@@ -2,10 +2,19 @@ InviteRedeemer = Struct.new(:invite) do
 
   def redeem
     Invite.transaction do
-      process_invitation if invite_was_redeemed?
+      if invite_was_redeemed?
+        process_invitation
+        return invited_user
+      end
     end
 
-    invited_user
+    # If `invite_passthrough_hours` is defined, allow them to re-use the invite link
+    # to login again.
+    if invite.redeemed_at >= SiteSetting.invite_passthrough_hours.hours.ago
+      return invited_user
+    end
+
+    nil
   end
 
   # extracted from User cause it is very specific to invites

config/locales/server.en.yml

@@ -713,6 +713,7 @@ en:
     force_hostname: "DEVELOPER ONLY! WARNING! Specify a hostname in the URL. Leave blank for default."
 
     invite_expiry_days: "How long user invitation keys are valid, in days"
+    invite_passthrough_hours: "How long a user can use a previously redeemed invitation key to log in, in hours"
 
     # TODO: perhaps we need a way of protecting these settings for hosted solution, global settings ...
 

config/site_settings.yml

@@ -247,7 +247,8 @@ users:
   enable_names:
     client: true
     default: true
-  invite_expiry_days: 4
+  invite_expiry_days: 1
+  invite_passthrough_hours: 0
   invites_shown:
     client: true
     default: 30

spec/models/invite_spec.rb

@@ -197,11 +197,26 @@ describe Invite do
 
 
         context 'again' do
-          it 'will not redeem twice' do
-            invite.redeem.should == user
-            invite.redeem.send_welcome_message.should be_false
+          context "without a passthrough" do
+            before do
+              SiteSetting.invite_passthrough_hours = 0
+            end
+
+            it 'will not redeem twice' do
+              invite.redeem.should be_blank
+            end
           end
 
+          context "with a passthrough" do
+            before do
+              SiteSetting.invite_passthrough_hours = 1
+            end
+
+            it 'will not redeem twice' do
+              invite.redeem.should be_present
+              invite.redeem.send_welcome_message.should be_false
+            end
+          end
         end
       end