From dc7c10e63dc5f0d582b8f875fdee1d5679eee3a7 Mon Sep 17 00:00:00 2001
From: Adam Grare <agrare@redhat.com>
Date: Thu, 9 Jul 2020 11:44:29 -0400
Subject: [PATCH 1/2] Use Host#uid_ems to link host records to ems_events

If we are unable to find the host by ems_ref attempt to use the
host_uid_ems attribute
---
 app/models/ems_event.rb       | 10 ++++++++++
 spec/models/ems_event_spec.rb | 28 ++++++++++++++++++++++++++++
 2 files changed, 38 insertions(+)

diff --git a/app/models/ems_event.rb b/app/models/ems_event.rb
index f6b94ff9417..ac79a5f2785 100644
--- a/app/models/ems_event.rb
+++ b/app/models/ems_event.rb
@@ -90,7 +90,17 @@ def self.process_vm_in_event!(event, options = {})
   end
 
   def self.process_host_in_event!(event, options = {})
+    uid_ems = event.delete(:host_uid_ems)
     process_object_in_event!(Host, event, options)
+
+    if event[:host_id].nil? && uid_ems.present?
+      # Attempt to find a host in the current EMS first, then fallback to archived hosts
+      host = Host.find_by(:ems_id => event[:ems_id], :uid_ems => uid_ems) || Host.find_by(:ems_id => nil, :uid_ems => uid_ems)
+      unless host.nil?
+        event[:host_id]     = host.id
+        event[:host_name] ||= host.name
+      end
+    end
   end
 
   def self.process_container_entities_in_event!(event, _options = {})
diff --git a/spec/models/ems_event_spec.rb b/spec/models/ems_event_spec.rb
index 926b36f8669..31ada2bb94d 100644
--- a/spec/models/ems_event_spec.rb
+++ b/spec/models/ems_event_spec.rb
@@ -275,6 +275,34 @@
         end
       end
     end
+
+    context "with a host" do
+      let(:event) do
+        {
+          :ems_id       => ems.id,
+          :event_type   => "HostAddEvent",
+          :host_uid_ems => host.uid_ems
+        }
+      end
+
+      context "with an active host" do
+        let(:host) { FactoryBot.create(:host, :uid_ems => "6f3fa3f1-bbe0-4aab-9a69-5d652324357f", :ext_management_system => ems) }
+
+        it "should link the event to the host" do
+          ems_event = described_class.add(ems.id, event)
+          expect(ems_event.host).to eq(host)
+        end
+      end
+
+      context "with an archived host" do
+        let(:host) { FactoryBot.create(:host, :uid_ems => "6f3fa3f1-bbe0-4aab-9a69-5d652324357f") }
+
+        it "should link the event to the host" do
+          ems_event = described_class.add(ems.id, event)
+          expect(ems_event.host).to eq(host)
+        end
+      end
+    end
   end
 
   context '.event_groups' do

From 78fec932f94df3584ba146149124e4318ca955b1 Mon Sep 17 00:00:00 2001
From: Adam Grare <agrare@redhat.com>
Date: Fri, 10 Jul 2020 08:14:38 -0400
Subject: [PATCH 2/2] Optimize query and add spec test for dup uid_ems's

---
 app/models/ems_event.rb       |  2 +-
 spec/models/ems_event_spec.rb | 10 ++++++++++
 2 files changed, 11 insertions(+), 1 deletion(-)

diff --git a/app/models/ems_event.rb b/app/models/ems_event.rb
index ac79a5f2785..24d9e6f301d 100644
--- a/app/models/ems_event.rb
+++ b/app/models/ems_event.rb
@@ -95,7 +95,7 @@ def self.process_host_in_event!(event, options = {})
 
     if event[:host_id].nil? && uid_ems.present?
       # Attempt to find a host in the current EMS first, then fallback to archived hosts
-      host = Host.find_by(:ems_id => event[:ems_id], :uid_ems => uid_ems) || Host.find_by(:ems_id => nil, :uid_ems => uid_ems)
+      host = Host.where(:uid_ems => uid_ems, :ems_id => [event[:ems_id], nil]).order("ems_id NULLS LAST").first
       unless host.nil?
         event[:host_id]     = host.id
         event[:host_name] ||= host.name
diff --git a/spec/models/ems_event_spec.rb b/spec/models/ems_event_spec.rb
index 31ada2bb94d..4f7436ce16b 100644
--- a/spec/models/ems_event_spec.rb
+++ b/spec/models/ems_event_spec.rb
@@ -302,6 +302,16 @@
           expect(ems_event.host).to eq(host)
         end
       end
+
+      context "with active and archived hosts with the same uid_ems" do
+        let!(:archived_host) { FactoryBot.create(:host, :uid_ems => "6f3fa3f1-bbe0-4aab-9a69-5d652324357f") }
+        let!(:host)          { FactoryBot.create(:host, :uid_ems => "6f3fa3f1-bbe0-4aab-9a69-5d652324357f", :ext_management_system => ems) }
+
+        it "should prefer the active host" do
+          ems_event = described_class.add(ems.id, event)
+          expect(ems_event.host).to eq(host)
+        end
+      end
     end
   end