Implement the SAP systems payload decoding and usage (#602)

* Implement the SAP systems payload decoding and usage

* Embed children module in the main payload module

* Privatize functions that are only meant for local usage

lib/trento/application/integration/discovery/payloads/sap_system_discovery_payload.ex

@@ -0,0 +1,351 @@
+defmodule Trento.Integration.Discovery.SapSystemDiscoveryPayload do
+  @moduledoc """
+  SAP system discovery integration event payload
+  """
+
+  alias Trento.Integration.Discovery.SapSystemDiscoveryPayload.{
+    Database,
+    Instance,
+    Profile
+  }
+
+  @required_fields [:Id, :SID, :Type, :Profile, :Databases, :Instances]
+
+  use Trento.Type
+
+  deftype do
+    field :Id, :string
+    field :SID, :string
+    field :Type, :integer
+    field :DBAddress, :string
+
+    embeds_one :Profile, Profile
+    embeds_many :Databases, Database
+    embeds_many :Instances, Instance
+  end
+
+  def changeset(sap_system, attrs) do
+    modified_attrs =
+      attrs
+      |> databases_to_list
+
+    sap_system
+    |> cast(modified_attrs, fields())
+    |> cast_embed(:Profile, with: {Profile, :changeset, [parse_system_type(attrs)]})
+    |> cast_embed(:Databases)
+    |> cast_embed(:Instances)
+    |> validate_required_fields(@required_fields)
+  end
+
+  defp parse_system_type(%{"Type" => system_type}), do: system_type
+  defp parse_system_type(_), do: nil
+
+  defp databases_to_list(%{"Databases" => nil} = attrs),
+    do: %{attrs | "Databases" => []}
+
+  defp databases_to_list(attrs), do: attrs
+
+  defmodule Profile do
+    @moduledoc """
+    Profile field payload
+    """
+
+    @application_type 2
+    @application_required_fields [:"dbs/hdb/dbname"]
+
+    # Cannot use Trento.Type here, Jason.Encoder is breaking the schema creation
+    use Ecto.Schema
+    import Ecto.Changeset
+
+    @type t() :: %__MODULE__{}
+
+    @primary_key false
+
+    embedded_schema do
+      field :"dbs/hdb/dbname", :string
+    end
+
+    def changeset(profile, attrs, type) do
+      profile
+      |> cast(attrs, __MODULE__.__schema__(:fields))
+      |> maybe_validate_required_fields(type)
+    end
+
+    defp maybe_validate_required_fields(changeset, @application_type),
+      do:
+        changeset
+        |> validate_required(@application_required_fields)
+
+    defp maybe_validate_required_fields(changeset, _), do: changeset
+  end
+
+  defmodule Database do
+    @moduledoc """
+    Databases field payload
+    """
+
+    @required_fields [:Database]
+
+    use Trento.Type
+
+    deftype do
+      field :Host, :string
+      field :User, :string
+      field :Group, :string
+      field :Active, :string
+      field :UserId, :string
+      field :GroupId, :string
+      field :SqlPort, :string
+      field :Database, :string
+      field :Container, :string
+    end
+
+    def changeset(database, attrs) do
+      database
+      |> cast(attrs, fields())
+      |> validate_required_fields(@required_fields)
+    end
+  end
+
+  defmodule Instance do
+    @moduledoc """
+    Instances field payload
+    """
+
+    alias Trento.Integration.Discovery.SapSystemDiscoveryPayload.{
+      SapControl,
+      SystemReplication
+    }
+
+    @required_fields [:Host, :Name, :Type, :SAPControl, :SystemReplication]
+
+    use Trento.Type
+
+    deftype do
+      field :Host, :string
+      field :Name, :string
+      field :Type, :integer
+
+      embeds_one :SAPControl, SapControl
+      embeds_one :SystemReplication, SystemReplication
+    end
+
+    def changeset(instance, attrs) do
+      instance
+      |> cast(attrs, fields())
+      |> cast_embed(:SAPControl)
+      |> cast_embed(:SystemReplication)
+      |> validate_required_fields(@required_fields)
+    end
+  end
+
+  defmodule SapControl do
+    @moduledoc """
+    SAP control field payload
+    """
+
+    alias Trento.Integration.Discovery.SapSystemDiscoveryPayload.{
+      SapControlInstance,
+      SapControlProcess,
+      SapControlProperty
+    }
+
+    @required_fields [:Properties, :Instances, :Processes]
+
+    use Trento.Type
+
+    deftype do
+      embeds_many :Properties, SapControlProperty
+      embeds_many :Instances, SapControlInstance
+      embeds_many :Processes, SapControlProcess
+    end
+
+    def changeset(sap_control, attrs) do
+      hostname = find_property("SAPLOCALHOST", attrs)
+
+      instance_number =
+        case find_property("SAPSYSTEM", attrs) do
+          instance_number when is_binary(instance_number) -> String.to_integer(instance_number)
+          _ -> nil
+        end
+
+      sap_control
+      |> cast(attrs, fields())
+      |> cast_embed(:Properties)
+      |> cast_embed(:Instances,
+        with: {SapControlInstance, :changeset, [hostname, instance_number]}
+      )
+      |> cast_embed(:Processes)
+      |> validate_required_fields(@required_fields)
+    end
+
+    defp find_property(property, %{"Properties" => properties}) do
+      properties
+      |> Enum.find_value(fn
+        %{"property" => ^property, "value" => value} -> value
+        _ -> nil
+      end)
+    end
+
+    defp find_property(_, _), do: nil
+  end
+
+  defmodule SapControlProperty do
+    @moduledoc """
+    SAP control property field payload
+    """
+
+    @required_fields [:value, :property]
+
+    use Trento.Type
+
+    deftype do
+      field :value, :string
+      field :property, :string
+      field :propertytype, :string
+    end
+
+    def changeset(property, attrs) do
+      property
+      |> cast(attrs, fields())
+      |> validate_required_fields(@required_fields)
+    end
+  end
+
+  defmodule SapControlInstance do
+    @moduledoc """
+    SAP control instances field payload
+    """
+
+    @required_fields [
+      :features,
+      :hostname,
+      :httpPort,
+      :httpsPort,
+      :dispstatus,
+      :instanceNr,
+      :startPriority
+    ]
+
+    use Trento.Type
+
+    deftype do
+      # current_instance is a custom field to make data extraction easier
+      field :current_instance, :boolean, default: false
+      field :features, :string
+      field :hostname, :string
+      field :httpPort, :integer
+      field :httpsPort, :integer
+
+      field :dispstatus, Ecto.Enum,
+        values: [
+          :"SAPControl-GREEN",
+          :"SAPControl-YELLOW",
+          :"SAPControl-RED",
+          :"SAPControl-GRAY"
+        ]
+
+      field :instanceNr, :integer
+      field :startPriority, :string
+    end
+
+    def changeset(instance, attrs, hostname, instance_number) do
+      enriched_attrs = enrich_current_instance(attrs, hostname, instance_number)
+
+      instance
+      |> cast(enriched_attrs, fields())
+      |> validate_required_fields(@required_fields)
+    end
+
+    defp enrich_current_instance(
+           %{"hostname" => current_hostname, "instanceNr" => current_instance_number} = attrs,
+           hostname,
+           instance_number
+         )
+         when hostname == current_hostname and instance_number == current_instance_number,
+         do: Map.put(attrs, "current_instance", true)
+
+    defp enrich_current_instance(attrs, _, _), do: attrs
+  end
+
+  defmodule SapControlProcess do
+    @moduledoc """
+    SAP control process field payload
+    """
+
+    @required_fields [
+      :pid,
+      :name,
+      :starttime,
+      :dispstatus,
+      :textstatus,
+      :description,
+      :elapsedtime
+    ]
+
+    use Trento.Type
+
+    deftype do
+      field :pid, :integer
+      field :name, :string
+      field :starttime, :string
+
+      field :dispstatus, Ecto.Enum,
+        values: [
+          :"SAPControl-GREEN",
+          :"SAPControl-YELLOW",
+          :"SAPControl-RED",
+          :"SAPControl-GRAY"
+        ]
+
+      field :description, :string
+      field :elapsedtime, :string
+    end
+
+    def changeset(process, attrs) do
+      process
+      |> cast(attrs, fields())
+      |> validate_required_fields(@required_fields)
+    end
+  end
+
+  defmodule SystemReplication do
+    @moduledoc """
+    SystemReplication process field payload
+    """
+
+    @required_fields [:local_site_id]
+
+    # Cannot use Trento.Type here, Jason.Encoder is breaking the schema creation
+    use Ecto.Schema
+    import Ecto.Changeset
+
+    @type t() :: %__MODULE__{}
+
+    @primary_key false
+
+    embedded_schema do
+      field :local_site_id, :string
+      field :overall_replication_status, :string
+      field :"site/1/REPLICATION_MODE", :string
+      field :"site/2/REPLICATION_MODE", :string
+    end
+
+    def changeset(system_replication, attrs) do
+      local_site_id = parse_local_site_id(attrs)
+
+      system_replication
+      |> cast(attrs, __MODULE__.__schema__(:fields))
+      |> validate_required(@required_fields)
+      |> validate_replication_mode(local_site_id)
+    end
+
+    defp parse_local_site_id(%{"local_site_id" => local_site_id}), do: local_site_id
+    defp parse_local_site_id(_), do: 1
+
+    defp validate_replication_mode(changeset, local_site_id) do
+      changeset
+      |> validate_required([:"site/#{local_site_id}/REPLICATION_MODE"])
+    end
+  end
+end