[#3213] Reorganized hashtags cleanup. Transaction-wrapped Hashtag.get_or_create_by_na...
[akkoma] / lib / pleroma / hashtag.ex
1 # Pleroma: A lightweight social networking server
2 # Copyright © 2017-2020 Pleroma Authors <https://pleroma.social/>
3 # SPDX-License-Identifier: AGPL-3.0-only
4
5 defmodule Pleroma.Hashtag do
6 use Ecto.Schema
7
8 import Ecto.Changeset
9 import Ecto.Query
10
11 alias Ecto.Multi
12 alias Pleroma.Hashtag
13 alias Pleroma.Object
14 alias Pleroma.Repo
15
16 schema "hashtags" do
17 field(:name, :string)
18
19 many_to_many(:objects, Object, join_through: "hashtags_objects", on_replace: :delete)
20
21 timestamps()
22 end
23
24 def get_by_name(name) do
25 Repo.get_by(Hashtag, name: name)
26 end
27
28 def get_or_create_by_name(name) when is_bitstring(name) do
29 with %Hashtag{} = hashtag <- get_by_name(name) do
30 {:ok, hashtag}
31 else
32 _ ->
33 %Hashtag{}
34 |> changeset(%{name: name})
35 |> Repo.insert()
36 end
37 end
38
39 def get_or_create_by_names(names) when is_list(names) do
40 timestamp = NaiveDateTime.truncate(NaiveDateTime.utc_now(), :second)
41
42 structs =
43 Enum.map(names, fn name ->
44 %Hashtag{}
45 |> changeset(%{name: name})
46 |> Map.get(:changes)
47 |> Map.merge(%{inserted_at: timestamp, updated_at: timestamp})
48 end)
49
50 with {:ok, %{query_op: hashtags}} <-
51 Multi.new()
52 |> Multi.insert_all(:insert_all_op, Hashtag, structs, on_conflict: :nothing)
53 |> Multi.run(:query_op, fn _repo, _changes ->
54 {:ok, Repo.all(from(ht in Hashtag, where: ht.name in ^names))}
55 end)
56 |> Repo.transaction() do
57 {:ok, hashtags}
58 else
59 {:error, _name, value, _changes_so_far} -> {:error, value}
60 end
61 end
62
63 def changeset(%Hashtag{} = struct, params) do
64 struct
65 |> cast(params, [:name])
66 |> update_change(:name, &String.downcase/1)
67 |> validate_required([:name])
68 |> unique_constraint(:name)
69 end
70
71 def unlink(%Object{id: object_id}) do
72 with {_, hashtag_ids} <-
73 from(hto in "hashtags_objects",
74 where: hto.object_id == ^object_id,
75 select: hto.hashtag_id
76 )
77 |> Repo.delete_all() do
78 delete_unreferenced(hashtag_ids)
79 end
80 end
81
82 @delete_unreferenced_query """
83 DELETE FROM hashtags WHERE id IN
84 (SELECT hashtags.id FROM hashtags
85 LEFT OUTER JOIN hashtags_objects
86 ON hashtags_objects.hashtag_id = hashtags.id
87 WHERE hashtags_objects.hashtag_id IS NULL AND hashtags.id = ANY($1));
88 """
89
90 def delete_unreferenced(ids) do
91 with {:ok, %{num_rows: deleted_count}} <- Repo.query(@delete_unreferenced_query, [ids]) do
92 {:ok, deleted_count}
93 end
94 end
95 end