philomena/lib/philomena/user_downvote_wipe.ex
2019-12-17 00:44:24 -05:00

72 lines
2.1 KiB
Elixir

defmodule Philomena.UserDownvoteWipe do
alias Philomena.Images.Image
alias Philomena.Images
alias Philomena.ImageVotes.ImageVote
alias Philomena.ImageFaves.ImageFave
alias Philomena.Repo
import Ecto.Query
def perform(user, upvotes_and_faves_too \\ false) do
ImageVote
|> where(user_id: ^user.id, up: false)
|> in_batches(fn queryable, image_ids ->
Repo.delete_all(where(queryable, [iv], iv.image_id in ^image_ids))
Repo.update_all(where(Image, [i], i.id in ^image_ids), inc: [downvotes_count: -1, score: 1])
Images.reindex_images(image_ids)
# Allow time for indexing to catch up
:timer.sleep(:timer.seconds(10))
end)
if upvotes_and_faves_too do
ImageVote
|> where(user_id: ^user.id, up: true)
|> in_batches(fn queryable, image_ids ->
Repo.delete_all(where(queryable, [iv], iv.image_id in ^image_ids))
Repo.update_all(where(Image, [i], i.id in ^image_ids), inc: [upvotes_count: -1, score: -1])
Images.reindex_images(image_ids)
:timer.sleep(:timer.seconds(10))
end)
ImageFave
|> where(user_id: ^user.id)
|> in_batches(fn queryable, image_ids ->
Repo.delete_all(where(queryable, [iv], iv.image_id in ^image_ids))
Repo.update_all(where(Image, [i], i.id in ^image_ids), inc: [faves_count: -1])
Images.reindex_images(image_ids)
:timer.sleep(:timer.seconds(10))
end)
end
end
# todo: extract this to its own module somehow
defp in_batches(queryable, mapper) do
queryable = order_by(queryable, asc: :image_id)
ids =
queryable
|> select([q], q.image_id)
|> limit(1000)
|> Repo.all()
queryable
|> in_batches(mapper, 1000, ids)
end
defp in_batches(_queryable, _mapper, _batch_size, []), do: nil
defp in_batches(queryable, mapper, batch_size, ids) do
mapper.(exclude(queryable, :order_by), ids)
ids =
queryable
|> where([q], q.image_id > ^Enum.max(ids))
|> select([q], q.image_id)
|> limit(^batch_size)
|> Repo.all()
in_batches(queryable, mapper, batch_size, ids)
end
end