forked from fedi/mastodon
73 lines
2.7 KiB
Ruby
73 lines
2.7 KiB
Ruby
|
# frozen_string_literal: true
|
||
|
|
|
||
|
|
module StatusSafeReblogInsert
|
||
|
|
extend ActiveSupport::Concern
|
||
|
|
|
||
|
|
class_methods do
|
||
|
|
# This is a hack to ensure that no reblogs of discarded statuses are created,
|
||
|
|
# as this cannot be enforced through database constraints the same way we do
|
||
|
|
# for reblogs of deleted statuses.
|
||
|
|
#
|
||
|
|
# To achieve this, we redefine the internal method responsible for issuing
|
||
|
|
# the "INSERT" statement and replace the "INSERT INTO ... VALUES ..." query
|
||
|
|
# with an "INSERT INTO ... SELECT ..." query with a "WHERE deleted_at IS NULL"
|
||
|
|
# clause on the reblogged status to ensure consistency at the database level.
|
||
|
|
#
|
||
|
|
# Otherwise, the code is kept as close as possible to ActiveRecord::Persistence
|
||
|
|
# code, and actually calls it if we are not handling a reblog.
|
||
|
|
def _insert_record(values)
|
||
|
|
return super unless values.is_a?(Hash) && values['reblog_of_id'].present?
|
||
|
|
|
||
|
|
primary_key = self.primary_key
|
||
|
|
primary_key_value = nil
|
||
|
|
|
||
|
|
if primary_key
|
||
|
|
primary_key_value = values[primary_key]
|
||
|
|
|
||
|
|
if !primary_key_value && prefetch_primary_key?
|
||
|
|
primary_key_value = next_sequence_value
|
||
|
|
values[primary_key] = primary_key_value
|
||
|
|
end
|
||
|
|
end
|
||
|
|
|
||
|
|
# The following line is where we differ from stock ActiveRecord implementation
|
||
|
|
im = _compile_reblog_insert(values)
|
||
|
|
|
||
|
|
# Since we are using SELECT instead of VALUES, a non-error `nil` return is possible.
|
||
|
|
# For our purposes, it's equivalent to a foreign key constraint violation
|
||
|
|
result = connection.insert(im, "#{self} Create", primary_key || false, primary_key_value)
|
||
|
|
raise ActiveRecord::InvalidForeignKey, "(reblog_of_id)=(#{values['reblog_of_id']}) is not present in table \"statuses\"" if result.nil?
|
||
|
|
|
||
|
|
result
|
||
|
|
end
|
||
|
|
|
||
|
|
def _compile_reblog_insert(values)
|
||
|
|
# This is somewhat equivalent to the following code of ActiveRecord::Persistence:
|
||
|
|
# `arel_table.compile_insert(_substitute_values(values))`
|
||
|
|
# The main difference is that we use a `SELECT` instead of a `VALUES` clause,
|
||
|
|
# which means we have to build the `SELECT` clause ourselves and do a bit more
|
||
|
|
# manual work.
|
||
|
|
|
||
|
|
# Instead of using Arel::InsertManager#values, we are going to use Arel::InsertManager#select
|
||
|
|
im = Arel::InsertManager.new
|
||
|
|
im.into(arel_table)
|
||
|
|
|
||
|
|
binds = []
|
||
|
|
reblog_bind = nil
|
||
|
|
values.each do |name, value|
|
||
|
|
attr = arel_table[name]
|
||
|
|
bind = predicate_builder.build_bind_attribute(attr.name, value)
|
||
|
|
|
||
|
|
im.columns << attr
|
||
|
|
binds << bind
|
||
|
|
|
||
|
|
reblog_bind = bind if name == 'reblog_of_id'
|
||
|
|
end
|
||
|
|
|
||
|
|
im.select(arel_table.where(arel_table[:id].eq(reblog_bind)).where(arel_table[:deleted_at].eq(nil)).project(*binds))
|
||
|
|
|
||
|
|
im
|
||
|
|
end
|
||
|
|
end
|
||
|
|
end
|