debian-mirror-gitlab/lib/gitlab/database/lock_writes_manager.rb

81 lines
2.2 KiB
Ruby
Raw Normal View History

2022-08-27 11:52:29 +05:30
# frozen_string_literal: true
module Gitlab
module Database
class LockWritesManager
TRIGGER_FUNCTION_NAME = 'gitlab_schema_prevent_write'
def initialize(table_name:, connection:, database_name:, logger: nil)
@table_name = table_name
@connection = connection
@database_name = database_name
@logger = logger
end
def lock_writes
logger&.info "Database: '#{database_name}', Table: '#{table_name}': Lock Writes".color(:yellow)
sql = <<-SQL
DROP TRIGGER IF EXISTS #{write_trigger_name(table_name)} ON #{table_name};
CREATE TRIGGER #{write_trigger_name(table_name)}
BEFORE INSERT OR UPDATE OR DELETE OR TRUNCATE
ON #{table_name}
FOR EACH STATEMENT EXECUTE FUNCTION #{TRIGGER_FUNCTION_NAME}();
SQL
with_retries(connection) do
connection.execute(sql)
end
end
def unlock_writes
logger&.info "Database: '#{database_name}', Table: '#{table_name}': Allow Writes".color(:green)
sql = <<-SQL
DROP TRIGGER IF EXISTS #{write_trigger_name(table_name)} ON #{table_name}
SQL
with_retries(connection) do
connection.execute(sql)
end
end
private
attr_reader :table_name, :connection, :database_name, :logger
def with_retries(connection, &block)
with_statement_timeout_retries do
with_lock_retries(connection) do
yield
end
end
end
def with_statement_timeout_retries(times = 5)
current_iteration = 1
begin
yield
rescue ActiveRecord::QueryCanceled => err # rubocop:disable Database/RescueQueryCanceled
if current_iteration <= times
current_iteration += 1
retry
else
raise err
end
end
end
def with_lock_retries(connection, &block)
Gitlab::Database::WithLockRetries.new(
klass: "gitlab:db:lock_writes",
logger: logger || Gitlab::AppLogger,
connection: connection
).run(&block)
end
def write_trigger_name(table_name)
"gitlab_schema_write_trigger_for_#{table_name}"
end
end
end
end