diff --git a/lib/pleroma/chat.ex b/lib/pleroma/chat.ex
new file mode 100644
index 000000000..e2a8b8eba
--- /dev/null
+++ b/lib/pleroma/chat.ex
@@ -0,0 +1,41 @@
+# Pleroma: A lightweight social networking server
+# Copyright © 2017-2020 Pleroma Authors
+# SPDX-License-Identifier: AGPL-3.0-only
+
+defmodule Pleroma.Chat do
+ use Ecto.Schema
+ import Ecto.Changeset
+
+ alias Pleroma.User
+ alias Pleroma.Repo
+
+ @moduledoc """
+ Chat keeps a reference to DirectMessage conversations between a user and an recipient. The recipient can be a user (for now) or a group (not implemented yet).
+
+ It is a helper only, to make it easy to display a list of chats with other people, ordered by last bump. The actual messages are retrieved by querying the recipients of the ChatMessages.
+ """
+
+ schema "chats" do
+ belongs_to(:user, User, type: FlakeId.Ecto.CompatType)
+ field(:recipient, :string)
+ field(:unread, :integer, default: 0)
+
+ timestamps()
+ end
+
+ def creation_cng(struct, params) do
+ struct
+ |> cast(params, [:user_id, :recipient])
+ |> validate_required([:user_id, :recipient])
+ |> unique_constraint(:user_id, name: :chats_user_id_recipient_index)
+ end
+
+ def get_or_create(user_id, recipient) do
+ %__MODULE__{}
+ |> creation_cng(%{user_id: user_id, recipient: recipient})
+ |> Repo.insert(
+ on_conflict: [set: [updated_at: NaiveDateTime.utc_now()]],
+ conflict_target: [:user_id, :recipient]
+ )
+ end
+end
diff --git a/priv/repo/migrations/20200309123730_create_chats.exs b/priv/repo/migrations/20200309123730_create_chats.exs
new file mode 100644
index 000000000..715d798ea
--- /dev/null
+++ b/priv/repo/migrations/20200309123730_create_chats.exs
@@ -0,0 +1,16 @@
+defmodule Pleroma.Repo.Migrations.CreateChats do
+ use Ecto.Migration
+
+ def change do
+ create table(:chats) do
+ add(:user_id, references(:users, type: :uuid))
+ # Recipient is an ActivityPub id, to future-proof for group support.
+ add(:recipient, :string)
+ add(:unread, :integer, default: 0)
+ timestamps()
+ end
+
+ # There's only one chat between a user and a recipient.
+ create(index(:chats, [:user_id, :recipient], unique: true))
+ end
+end
diff --git a/test/chat_test.exs b/test/chat_test.exs
new file mode 100644
index 000000000..ca9206802
--- /dev/null
+++ b/test/chat_test.exs
@@ -0,0 +1,44 @@
+# Pleroma: A lightweight social networking server
+# Copyright © 2017-2020 Pleroma Authors
+# SPDX-License-Identifier: AGPL-3.0-only
+
+defmodule Pleroma.ChatTest do
+ use Pleroma.DataCase, async: true
+
+ alias Pleroma.Chat
+
+ import Pleroma.Factory
+
+ describe "creation and getting" do
+ test "it creates a chat for a user and recipient" do
+ user = insert(:user)
+ other_user = insert(:user)
+
+ {:ok, chat} = Chat.get_or_create(user.id, other_user.ap_id)
+
+ assert chat.id
+ end
+
+ test "it returns a chat for a user and recipient if it already exists" do
+ user = insert(:user)
+ other_user = insert(:user)
+
+ {:ok, chat} = Chat.get_or_create(user.id, other_user.ap_id)
+ {:ok, chat_two} = Chat.get_or_create(user.id, other_user.ap_id)
+
+ assert chat.id == chat_two.id
+ end
+
+ test "a returning chat will have an updated `update_at` field" do
+ user = insert(:user)
+ other_user = insert(:user)
+
+ {:ok, chat} = Chat.get_or_create(user.id, other_user.ap_id)
+ :timer.sleep(1500)
+ {:ok, chat_two} = Chat.get_or_create(user.id, other_user.ap_id)
+
+ assert chat.id == chat_two.id
+ assert chat.updated_at != chat_two.updated_at
+ end
+ end
+end