MastoAPI: Add user notes on accounts

Signed-off-by: marcin mikołajczak <git@mkljczk.pl>

lib/pleroma/user_note.ex

@@ -0,0 +1,52 @@
+# Pleroma: A lightweight social networking server
+# Copyright © 2017-2021 Pleroma Authors <https://pleroma.social/>
+# SPDX-License-Identifier: AGPL-3.0-only
+
+defmodule Pleroma.UserNote do
+  use Ecto.Schema
+
+  import Ecto.Changeset
+  import Ecto.Query
+
+  alias Pleroma.Repo
+  alias Pleroma.User
+  alias Pleroma.UserNote
+
+  schema "user_notes" do
+    belongs_to(:source, User, type: FlakeId.Ecto.CompatType)
+    belongs_to(:target, User, type: FlakeId.Ecto.CompatType)
+    field(:comment, :string)
+
+    timestamps()
+  end
+
+  def changeset(%UserNote{} = user_note, params \\ %{}) do
+    user_note
+    |> cast(params, [:source_id, :target_id, :comment])
+    |> validate_required([:source_id, :target_id])
+  end
+
+  def show(%User{} = source, %User{} = target) do
+    with %UserNote{} = note <-
+           UserNote
+           |> where(source_id: ^source.id, target_id: ^target.id)
+           |> Repo.one() do
+      note.comment
+    else
+      _ -> ""
+    end
+  end
+
+  def create(%User{} = source, %User{} = target, comment) do
+    %UserNote{}
+    |> changeset(%{
+      source_id: source.id,
+      target_id: target.id,
+      comment: comment
+    })
+    |> Repo.insert(
+      on_conflict: {:replace, [:comment]},
+      conflict_target: [:source_id, :target_id]
+    )
+  end
+end