philomena/lib/philomena/interactions.ex
2019-12-07 23:53:18 -05:00

102 lines
No EOL
3.3 KiB
Elixir

defmodule Philomena.Interactions do
import Ecto.Query
alias Philomena.ImageHides.ImageHide
alias Philomena.ImageFaves.ImageFave
alias Philomena.ImageVotes.ImageVote
alias Philomena.Images.Image
alias Philomena.Repo
alias Ecto.Multi
def user_interactions(_images, nil),
do: []
def user_interactions(images, user) do
ids =
images
|> Enum.flat_map(fn
nil -> []
%{id: id} -> [id]
enum -> Enum.map(enum, & &1.id)
end)
|> Enum.uniq()
hide_interactions =
ImageHide
|> select([h], %{image_id: h.image_id, user_id: h.user_id, interaction_type: ^"hidden", value: ^""})
|> where([h], h.image_id in ^ids)
|> where(user_id: ^user.id)
fave_interactions =
ImageFave
|> select([f], %{image_id: f.image_id, user_id: f.user_id, interaction_type: ^"faved", value: ^""})
|> where([f], f.image_id in ^ids)
|> where(user_id: ^user.id)
upvote_interactions =
ImageVote
|> select([v], %{image_id: v.image_id, user_id: v.user_id, interaction_type: ^"voted", value: ^"up"})
|> where([v], v.image_id in ^ids)
|> where(user_id: ^user.id, up: true)
downvote_interactions =
ImageVote
|> select([v], %{image_id: v.image_id, user_id: v.user_id, interaction_type: ^"voted", value: ^"down"})
|> where([v], v.image_id in ^ids)
|> where(user_id: ^user.id, up: false)
[
hide_interactions,
fave_interactions,
upvote_interactions,
downvote_interactions
]
|> union_all_queries()
|> Repo.all()
end
def migrate_interactions(source, target) do
now = DateTime.utc_now()
source = Repo.preload(source, [:hiders, :favers, :upvoters, :downvoters])
new_hides = Enum.map(source.hiders, &%{image_id: target.id, user_id: &1.id, created_at: now})
new_faves = Enum.map(source.favers, &%{image_id: target.id, user_id: &1.id, created_at: now})
new_upvotes = Enum.map(source.upvoters, &%{image_id: target.id, user_id: &1.id, created_at: now, up: true})
new_downvotes = Enum.map(source.downvoters, &%{image_id: target.id, user_id: &1.id, created_at: now, up: false})
Multi.new
|> Multi.run(:hides, fn repo, %{} ->
{count, nil} = repo.insert_all(ImageHide, new_hides, on_conflict: :nothing)
{:ok, count}
end)
|> Multi.run(:faves, fn repo, %{} ->
{count, nil} = repo.insert_all(ImageFave, new_faves, on_conflict: :nothing)
{:ok, count}
end)
|> Multi.run(:upvotes, fn repo, %{} ->
{count, nil} = repo.insert_all(ImageVote, new_upvotes, on_conflict: :nothing)
{:ok, count}
end)
|> Multi.run(:downvotes, fn repo, %{} ->
{count, nil} = repo.insert_all(ImageVote, new_downvotes, on_conflict: :nothing)
{:ok, count}
end)
|> Multi.run(:image, fn repo, %{hides: hides, faves: faves, upvotes: upvotes, downvotes: downvotes} ->
image_query = where(Image, id: ^target.id)
repo.update_all(image_query, inc: [hides: hides, faves: faves, upvotes: upvotes, downvotes: downvotes, score: upvotes - downvotes])
{:ok, nil}
end)
|> Repo.isolated_transaction(:serializable)
end
defp union_all_queries([query]),
do: query
defp union_all_queries([query | rest]),
do: query |> union_all(^union_all_queries(rest))
end