FEATURE: emit external_id field with user webhook

app/jobs/regular/emit_web_hook_event.rb

@@ -56,7 +56,6 @@ module Jobs
 
     def build_web_hook_body(args, web_hook)
       body = {}
-      guardian = Guardian.new(Discourse.system_user)
       event_type = args[:event_type].to_s
 
       if ping_event?(event_type)

app/serializers/web_hook_user_serializer.rb

@@ -1,4 +1,6 @@
 class WebHookUserSerializer < UserSerializer
+  attributes :external_id
+
   # remove staff attributes
   def staff_attributes(*attrs)
   end
@@ -6,4 +8,13 @@ class WebHookUserSerializer < UserSerializer
   def include_email?
     scope.is_admin?
   end
+
+  def include_external_id?
+    scope.is_admin? && object.single_sign_on_record
+  end
+
+  def external_id
+    object.single_sign_on_record.external_id
+  end
+
 end

spec/models/web_hook_spec.rb

@@ -188,7 +188,7 @@ describe WebHook do
     end
 
     it 'should enqueue the right hooks for user events' do
-      user_web_hook = Fabricate(:user_web_hook, active: true)
+      _user_web_hook = Fabricate(:user_web_hook, active: true)
 
       Sidekiq::Testing.fake! do
         user

spec/serializers/web_hook_user_serializer_spec.rb

@@ -1,14 +1,21 @@
 require 'rails_helper'
 
 RSpec.describe WebHookUserSerializer do
-  let(:user) { Fabricate(:user) }
+  let(:user) do
+    user = Fabricate(:user)
+    SingleSignOnRecord.create!(user_id: user.id, external_id: '12345', last_payload: '')
+    user
+  end
+
   let(:admin) { Fabricate(:admin) }
 
-  subject { described_class.new(user, scope: Guardian.new(admin), root: false) }
-
-  it "should include the user's email" do
-    payload = subject.as_json
+  let :serializer do
+    WebHookUserSerializer.new(user, scope: Guardian.new(admin), root: false)
+  end
 
+  it "should include relevant user info" do
+    payload = serializer.as_json
     expect(payload[:email]).to eq(user.email)
+    expect(payload[:external_id]).to eq('12345')
   end
 end