fix multiple counting bug on tag batch update (derpibooru/philomena#158)

This commit is contained in:
byte[] 2020-08-14 21:04:12 -04:00
parent 1a76cc484c
commit aef3cd399b

View file

@ -496,15 +496,16 @@ defmodule Philomena.Images do
now = NaiveDateTime.utc_now() |> NaiveDateTime.truncate(:second)
tag_change_attributes = Map.merge(tag_change_attributes, %{created_at: now, updated_at: now})
tag_attributes = %{name: "", slug: "", created_at: now, updated_at: now}
Repo.transaction(fn ->
{added_count, inserted} =
{_count, inserted} =
Repo.insert_all(Tagging, insertions,
on_conflict: :nothing,
returning: [:image_id, :tag_id]
)
{removed_count, deleted} = Repo.delete_all(deletions)
{_count, deleted} = Repo.delete_all(deletions)
inserted = Enum.map(inserted, &[&1.image_id, &1.tag_id])
@ -521,8 +522,30 @@ defmodule Philomena.Images do
changes = added_changes ++ removed_changes
Repo.insert_all(TagChange, changes)
Repo.update_all(where(Tag, [t], t.id in ^added_tags), inc: [images_count: added_count])
Repo.update_all(where(Tag, [t], t.id in ^removed_tags), inc: [images_count: -removed_count])
# In order to merge into the existing tables here in one go, insert_all
# is used with a query that is guaranteed to conflict on every row by
# using the primary key.
added_upserts =
inserted
|> Enum.group_by(fn [_image_id, tag_id] -> tag_id end)
|> Enum.map(fn {tag_id, instances} ->
Map.merge(tag_attributes, %{id: tag_id, images_count: length(instances)})
end)
removed_upserts =
deleted
|> Enum.group_by(fn [_image_id, tag_id] -> tag_id end)
|> Enum.map(fn {tag_id, instances} ->
Map.merge(tag_attributes, %{id: tag_id, images_count: -length(instances)})
end)
update_query = update(Tag, inc: [images_count: fragment("EXCLUDED.images_count")])
upserts = added_upserts ++ removed_upserts
Repo.insert_all(Tag, upserts, on_conflict: update_query, conflict_target: [:id])
end)
|> case do
{:ok, _} = result ->