akkoma/lib/pleroma/hashtag.ex
2022-06-30 16:28:31 +01:00

106 lines
2.8 KiB
Elixir

# Pleroma: A lightweight social networking server
# Copyright © 2017-2020 Pleroma Authors <https://pleroma.social/>
# SPDX-License-Identifier: AGPL-3.0-only
defmodule Pleroma.Hashtag do
use Ecto.Schema
import Ecto.Changeset
import Ecto.Query
alias Ecto.Multi
alias Pleroma.Hashtag
alias Pleroma.Object
alias Pleroma.Repo
schema "hashtags" do
field(:name, :string)
many_to_many(:objects, Object, join_through: "hashtags_objects", on_replace: :delete)
timestamps()
end
def normalize_name(name) do
name
|> String.downcase()
|> String.trim()
end
def get_or_create_by_name(name) do
changeset = changeset(%Hashtag{}, %{name: name})
Repo.insert(
changeset,
on_conflict: [set: [name: get_field(changeset, :name)]],
conflict_target: :name,
returning: true
)
end
def get_or_create_by_names(names) when is_list(names) do
names = Enum.map(names, &normalize_name/1)
timestamp = NaiveDateTime.truncate(NaiveDateTime.utc_now(), :second)
structs =
Enum.map(names, fn name ->
%Hashtag{}
|> changeset(%{name: name})
|> Map.get(:changes)
|> Map.merge(%{inserted_at: timestamp, updated_at: timestamp})
end)
try do
with {:ok, %{query_op: hashtags}} <-
Multi.new()
|> Multi.insert_all(:insert_all_op, Hashtag, structs,
on_conflict: :nothing,
conflict_target: :name
)
|> Multi.run(:query_op, fn _repo, _changes ->
{:ok, Repo.all(from(ht in Hashtag, where: ht.name in ^names))}
end)
|> Repo.transaction() do
{:ok, hashtags}
else
{:error, _name, value, _changes_so_far} -> {:error, value}
end
rescue
e -> {:error, e}
end
end
def changeset(%Hashtag{} = struct, params) do
struct
|> cast(params, [:name])
|> update_change(:name, &normalize_name/1)
|> validate_required([:name])
|> unique_constraint(:name)
end
def unlink(%Object{id: object_id}) do
with {_, hashtag_ids} <-
from(hto in "hashtags_objects",
where: hto.object_id == ^object_id,
select: hto.hashtag_id
)
|> Repo.delete_all(),
{:ok, unreferenced_count} <- delete_unreferenced(hashtag_ids) do
{:ok, length(hashtag_ids), unreferenced_count}
end
end
@delete_unreferenced_query """
DELETE FROM hashtags WHERE id IN
(SELECT hashtags.id FROM hashtags
LEFT OUTER JOIN hashtags_objects
ON hashtags_objects.hashtag_id = hashtags.id
WHERE hashtags_objects.hashtag_id IS NULL AND hashtags.id = ANY($1));
"""
def delete_unreferenced(ids) do
with {:ok, %{num_rows: deleted_count}} <- Repo.query(@delete_unreferenced_query, [ids]) do
{:ok, deleted_count}
end
end
end