Add initiation for software updates discovery process

lib/trento/hosts/commands/discover_software_updates.ex

@@ -0,0 +1,13 @@
+defmodule Trento.Hosts.Commands.DiscoverSoftwareUpdates do
+  @moduledoc """
+  Issues the software updates discovery for a host
+  """
+
+  @required_fields :all
+
+  use Trento.Support.Command
+
+  defcommand do
+    field :host_id, Ecto.UUID
+  end
+end

lib/trento/hosts/events/software_updates_discovery_requested.ex

@@ -0,0 +1,12 @@
+defmodule Trento.Hosts.Events.SoftwareUpdatesDiscoveryRequested do
+  @moduledoc """
+  This event is emitted when a host's software updates discovery process is issued
+  """
+
+  use Trento.Support.Event
+
+  defevent do
+    field :host_id, Ecto.UUID
+    field :fully_qualified_domain_name, :string
+  end
+end

lib/trento/hosts/host.ex

@@ -38,11 +38,17 @@ defmodule Trento.Hosts.Host do
   Every time a checks execution for a host completes the execution's result is taken into account to determine host's health.
   Checks execution is started either by an explicit user request or periodically as per the scheduler configuration.
 
-  ### Software Updates Discovery health
+  ### Software Updates Discovery
 
-  The Software Updates Discovery health is obtained from the integration with an external service, SUMA,
-  that provides information about relevant patches and upgradable packages for the host.
-  Presence of relevant patches concurs to the host's aggregated health as follows:
+  Business process integrating with an external service, SUMA, determining relevant patches and upgradable packages for a host.
+  Process is triggered
+  - on host registration
+  - when the fqdn of the host changes
+  - on host restoration
+  - every given amount of time
+  - on demand (ie the integration settings with the external service change)
+
+  Presence of relevant patches determines Software Updates Discovery health and concurs to the host's aggregated health as follows:
   - critical if there is at least one security advisory
   - warning if there are only buxfixes/software enhancements
   """
@@ -70,6 +76,7 @@ defmodule Trento.Hosts.Host do
     CompleteHostChecksExecution,
     CompleteSoftwareUpdatesDiscovery,
     DeregisterHost,
+    DiscoverSoftwareUpdates,
     RegisterHost,
     RequestHostDeregistration,
     RollUpHost,
@@ -99,7 +106,8 @@ defmodule Trento.Hosts.Host do
     SaptuneStatusUpdated,
     SlesSubscriptionsUpdated,
     SoftwareUpdatesDiscoveryCleared,
-    SoftwareUpdatesDiscoveryCompleted
+    SoftwareUpdatesDiscoveryCompleted,
+    SoftwareUpdatesDiscoveryRequested
   }
 
   @required_fields []
@@ -528,6 +536,21 @@ defmodule Trento.Hosts.Host do
     |> Multi.execute(&maybe_emit_host_health_changed_event/1)
   end
 
+  # Software Updates Discovery
+
+  def execute(
+        %Host{
+          host_id: host_id,
+          fully_qualified_domain_name: fully_qualified_domain_name
+        },
+        %DiscoverSoftwareUpdates{}
+      ) do
+    %SoftwareUpdatesDiscoveryRequested{
+      host_id: host_id,
+      fully_qualified_domain_name: fully_qualified_domain_name
+    }
+  end
+
   def execute(
         %Host{host_id: host_id} = host,
         %CompleteSoftwareUpdatesDiscovery{
@@ -714,6 +737,8 @@ defmodule Trento.Hosts.Host do
     }
   end
 
+  def apply(%Host{} = host, %SoftwareUpdatesDiscoveryRequested{}), do: host
+
   def apply(
         %Host{} = host,
         %SoftwareUpdatesDiscoveryCompleted{

lib/trento/router.ex

@@ -16,6 +16,7 @@ defmodule Trento.Router do
     CompleteHostChecksExecution,
     CompleteSoftwareUpdatesDiscovery,
     DeregisterHost,
+    DiscoverSoftwareUpdates,
     RegisterHost,
     RequestHostDeregistration,
     RollUpHost,
@@ -55,6 +56,7 @@ defmodule Trento.Router do
              RequestHostDeregistration,
              DeregisterHost,
              CompleteHostChecksExecution,
+             DiscoverSoftwareUpdates,
              CompleteSoftwareUpdatesDiscovery,
              ClearSoftwareUpdatesDiscovery
            ],

test/trento/hosts/host_test.exs

@@ -8,6 +8,7 @@ defmodule Trento.Hosts.HostTest do
     CompleteHostChecksExecution,
     CompleteSoftwareUpdatesDiscovery,
     DeregisterHost,
+    DiscoverSoftwareUpdates,
     RegisterHost,
     RequestHostDeregistration,
     RollUpHost,
@@ -37,7 +38,8 @@ defmodule Trento.Hosts.HostTest do
     SaptuneStatusUpdated,
     SlesSubscriptionsUpdated,
     SoftwareUpdatesDiscoveryCleared,
-    SoftwareUpdatesDiscoveryCompleted
+    SoftwareUpdatesDiscoveryCompleted,
+    SoftwareUpdatesDiscoveryRequested
   }
 
   alias Trento.Hosts.ValueObjects.{
@@ -1408,6 +1410,7 @@ defmodule Trento.Hosts.HostTest do
   describe "software updates discovery" do
     test "should not accept software updates discovery commands if a host is not registered yet" do
       commands = [
+        %DiscoverSoftwareUpdates{host_id: Faker.UUID.v4()},
         %CompleteSoftwareUpdatesDiscovery{host_id: Faker.UUID.v4()},
         %ClearSoftwareUpdatesDiscovery{host_id: Faker.UUID.v4()}
       ]
@@ -1417,6 +1420,37 @@ defmodule Trento.Hosts.HostTest do
       end
     end
 
+    test "should trigger the software updates discovery process" do
+      host_id = Faker.UUID.v4()
+      fully_qualified_domain_name = Faker.Internet.domain_name()
+
+      initial_events = [
+        build(:host_registered_event,
+          host_id: host_id,
+          fully_qualified_domain_name: fully_qualified_domain_name
+        ),
+        build(:heartbeat_succeded, host_id: host_id)
+      ]
+
+      assert_events_and_state(
+        initial_events,
+        DiscoverSoftwareUpdates.new!(%{
+          host_id: host_id
+        }),
+        %SoftwareUpdatesDiscoveryRequested{
+          host_id: host_id,
+          fully_qualified_domain_name: fully_qualified_domain_name
+        },
+        fn host ->
+          assert %Host{
+                   host_id: ^host_id,
+                   fully_qualified_domain_name: ^fully_qualified_domain_name,
+                   heartbeat: Health.passing()
+                 } = host
+        end
+      )
+    end
+
     defp get_host_health_changed_event(host_id, scenario) do
       case Map.get(scenario, :expect_host_health_changed, true) do
         true ->
@@ -1713,8 +1747,7 @@ defmodule Trento.Hosts.HostTest do
         }
       ]
 
-      assert_error(
-        events,
+      commands_to_reject = [
         UpdateProvider.new!(%{
           host_id: host_id,
           provider: :azure,
@@ -1729,16 +1762,15 @@ defmodule Trento.Hosts.HostTest do
             vpc_id: "vpc-12345"
           }
         }),
-        {:error, :host_rolling_up}
-      )
-
-      assert_error(
-        events,
+        DiscoverSoftwareUpdates.new!(%{host_id: host_id}),
         RollUpHost.new!(%{
           host_id: host_id
-        }),
-        {:error, :host_rolling_up}
-      )
+        })
+      ]
+
+      for command <- commands_to_reject do
+        assert_error(events, command, {:error, :host_rolling_up})
+      end
     end
 
     test "should apply the rollup event and rehydrate the aggregate" do
@@ -1914,6 +1946,7 @@ defmodule Trento.Hosts.HostTest do
         %UpdateHeartbeat{host_id: host_id},
         %UpdateProvider{host_id: host_id},
         %UpdateSlesSubscriptions{host_id: host_id},
+        %DiscoverSoftwareUpdates{host_id: host_id},
         %CompleteSoftwareUpdatesDiscovery{host_id: host_id},
         %ClearSoftwareUpdatesDiscovery{host_id: host_id},
         %SelectHostChecks{host_id: host_id}