akkoma/lib/pleroma/user/search.ex

269 lines
7.2 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.User.Search do
alias Pleroma.EctoType.ActivityPub.ObjectValidators.Uri, as: UriType
alias Pleroma.Pagination
alias Pleroma.User
import Ecto.Query
@limit 20
def search(query_string, opts \\ []) do
resolve = Keyword.get(opts, :resolve, false)
following = Keyword.get(opts, :following, false)
result_limit = Keyword.get(opts, :limit, @limit)
offset = Keyword.get(opts, :offset, 0)
for_user = Keyword.get(opts, :for_user)
query_string = format_query(query_string)
# If this returns anything, it should bounce to the top
maybe_resolved = maybe_resolve(resolve, for_user, query_string)
top_user_ids =
[]
|> maybe_add_resolved(maybe_resolved)
|> maybe_add_ap_id_match(query_string)
|> maybe_add_uri_match(query_string)
results =
query_string
|> search_query(for_user, following, top_user_ids)
|> Pagination.fetch_paginated(%{"offset" => offset, "limit" => result_limit}, :offset)
results
end
defp maybe_add_resolved(list, {:ok, %User{} = user}) do
[user.id | list]
end
defp maybe_add_resolved(list, _), do: list
defp maybe_add_ap_id_match(list, query) do
if user = User.get_cached_by_ap_id(query) do
[user.id | list]
else
list
end
end
defp maybe_add_uri_match(list, query) do
with {:ok, query} <- UriType.cast(query),
q = from(u in User, where: u.uri == ^query, select: u.id),
users = Pleroma.Repo.all(q) do
users ++ list
else
_ -> list
end
end
defp format_query(query_string) do
# Strip the beginning @ off if there is a query
query_string = String.trim_leading(query_string, "@")
with [name, domain] <- String.split(query_string, "@") do
encoded_domain =
domain
|> String.replace(~r/[!-\-|@|[-`|{-~|\/|:|\s]+/, "")
|> String.to_charlist()
|> :idna.encode()
|> to_string()
name <> "@" <> encoded_domain
else
_ -> query_string
end
end
defp search_query(query_string, for_user, following, top_user_ids) do
for_user
|> base_query(following)
|> filter_blocked_user(for_user)
|> filter_invisible_users()
|> filter_non_discoverable_users()
|> filter_internal_users()
|> filter_blocked_domains(for_user)
|> fts_search(query_string)
|> select_top_users(top_user_ids)
|> trigram_rank(query_string)
|> boost_search_rank(for_user, top_user_ids)
|> subquery()
|> order_by(desc: :search_rank)
|> maybe_restrict_local(for_user)
end
defp select_top_users(query, top_user_ids) do
from(u in query,
or_where: u.id in ^top_user_ids
)
end
defp fts_search(query, query_string) do
query_string = to_tsquery(query_string)
from(
u in query,
where:
fragment(
# The fragment must _exactly_ match `users_fts_index`, otherwise the index won't work
"""
(
setweight(to_tsvector('simple', regexp_replace(?, '\\W', ' ', 'g')), 'A') ||
setweight(to_tsvector('simple', regexp_replace(coalesce(?, ''), '\\W', ' ', 'g')), 'B')
) @@ to_tsquery('simple', ?)
""",
u.nickname,
u.name,
^query_string
)
)
end
defp to_tsquery(query_string) do
String.trim_trailing(query_string, "@" <> local_domain())
|> String.replace(~r/[!-\/|@|[-`|{-~|:-?]+/, " ")
|> String.trim()
|> String.split()
|> Enum.map(&(&1 <> ":*"))
|> Enum.join(" | ")
end
# Considers nickname match, localized nickname match, name match; preferences nickname match
defp trigram_rank(query, query_string) do
from(
u in query,
select_merge: %{
search_rank:
fragment(
"""
similarity(?, ?) +
similarity(?, regexp_replace(?, '@.+', '')) +
similarity(?, trim(coalesce(?, '')))
""",
^query_string,
u.nickname,
^query_string,
u.nickname,
^query_string,
u.name
)
}
)
end
defp base_query(%User{} = user, true), do: User.get_friends_query(user)
defp base_query(_user, _following), do: User
defp filter_invisible_users(query) do
from(q in query, where: q.invisible == false)
end
defp filter_non_discoverable_users(query) do
# Note: commented out — can't do it with users being non-discoverable by default
# from(q in query, where: q.is_discoverable == true)
query
end
defp filter_internal_users(query) do
from(q in query, where: q.actor_type != "Application")
end
defp filter_blocked_user(query, %User{} = blocker) do
query
|> join(:left, [u], b in Pleroma.UserRelationship,
as: :blocks,
on: b.relationship_type == ^:block and b.source_id == ^blocker.id and u.id == b.target_id
)
|> where([blocks: b], is_nil(b.target_id))
end
defp filter_blocked_user(query, _), do: query
defp filter_blocked_domains(query, %User{domain_blocks: domain_blocks})
when length(domain_blocks) > 0 do
domains = Enum.join(domain_blocks, ",")
from(
q in query,
where: fragment("substring(ap_id from '.*://([^/]*)') NOT IN (?)", ^domains)
)
end
defp filter_blocked_domains(query, _), do: query
defp maybe_resolve(true, user, query) do
case {limit(), user} do
{:all, _} -> :noop
{:unauthenticated, %User{}} -> User.get_or_fetch(query)
{:unauthenticated, _} -> :noop
{false, _} -> User.get_or_fetch(query)
end
end
defp maybe_resolve(_, _, _), do: :noop
defp maybe_restrict_local(q, user) do
case {limit(), user} do
{:all, _} -> restrict_local(q)
{:unauthenticated, %User{}} -> q
{:unauthenticated, _} -> restrict_local(q)
{false, _} -> q
end
end
defp limit, do: Pleroma.Config.get([:instance, :limit_to_local_content], :unauthenticated)
defp restrict_local(q), do: where(q, [u], u.local == true)
defp local_domain, do: Pleroma.Config.get([Pleroma.Web.Endpoint, :url, :host])
defp boost_search_rank(query, %User{} = for_user, top_user_ids) do
friends_ids = User.get_friends_ids(for_user)
followers_ids = User.get_followers_ids(for_user)
from(u in subquery(query),
select_merge: %{
search_rank:
fragment(
"""
CASE WHEN (?) THEN (?) * 1.5
WHEN (?) THEN (?) * 1.3
WHEN (?) THEN (?) * 1.1
WHEN (?) THEN 9001
ELSE (?) END
""",
u.id in ^friends_ids and u.id in ^followers_ids,
u.search_rank,
u.id in ^friends_ids,
u.search_rank,
u.id in ^followers_ids,
u.search_rank,
u.id in ^top_user_ids,
u.search_rank
)
}
)
end
defp boost_search_rank(query, _for_user, top_user_ids) do
from(u in subquery(query),
select_merge: %{
search_rank:
fragment(
"""
CASE WHEN (?) THEN 9001
ELSE (?) END
""",
u.id in ^top_user_ids,
u.search_rank
)
}
)
end
end