1 files changed, 0 insertions, 143 deletions
diff --git a/lib/gitlab/database/concurrent_reindex.rb b/lib/gitlab/database/concurrent_reindex.rb
deleted file mode 100644
index 485ab35e55d..00000000000
--- a/lib/gitlab/database/concurrent_reindex.rb
+++ /dev/null
@@ -1,143 +0,0 @@
-# frozen_string_literal: true
-
-module Gitlab
-  module Database
-    class ConcurrentReindex
-      include Gitlab::Utils::StrongMemoize
-      include MigrationHelpers
-
-      ReindexError = Class.new(StandardError)
-
-      PG_IDENTIFIER_LENGTH = 63
-      TEMPORARY_INDEX_PREFIX = 'tmp_reindex_'
-      REPLACED_INDEX_PREFIX = 'old_reindex_'
-
-      attr_reader :index_name, :logger
-
-      def initialize(index_name, logger:)
-        @index_name = index_name
-        @logger = logger
-      end
-
-      def execute
-        raise ReindexError, "index #{index_name} does not exist" unless index_exists?
-
-        raise ReindexError, 'UNIQUE indexes are currently not supported' if index_unique?
-
-        logger.debug("dropping dangling index from previous run: #{replacement_index_name}")
-        remove_replacement_index
-
-        begin
-          create_replacement_index
-
-          unless replacement_index_valid?
-            message = 'replacement index was created as INVALID'
-            logger.error("#{message}, cleaning up")
-            raise ReindexError, "failed to reindex #{index_name}: #{message}"
-          end
-
-          swap_replacement_index
-        rescue Gitlab::Database::WithLockRetries::AttemptsExhaustedError => e
-          logger.error('failed to obtain the required database locks to swap the indexes, cleaning up')
-          raise ReindexError, e.message
-        rescue ActiveRecord::ActiveRecordError, PG::Error => e
-          logger.error("database error while attempting reindex of #{index_name}: #{e.message}")
-          raise ReindexError, e.message
-        ensure
-          logger.info("dropping unneeded replacement index: #{replacement_index_name}")
-          remove_replacement_index
-        end
-      end
-
-      private
-
-      def connection
-        @connection ||= ActiveRecord::Base.connection
-      end
-
-      def replacement_index_name
-        @replacement_index_name ||= constrained_index_name(TEMPORARY_INDEX_PREFIX)
-      end
-
-      def index
-        strong_memoize(:index) do
-          find_index(index_name)
-        end
-      end
-
-      def index_exists?
-        !index.nil?
-      end
-
-      def index_unique?
-        index.indisunique
-      end
-
-      def constrained_index_name(prefix)
-        "#{prefix}#{index_name}".slice(0, PG_IDENTIFIER_LENGTH)
-      end
-
-      def create_replacement_index
-        create_replacement_index_statement = index.indexdef
-          .sub(/CREATE INDEX/, 'CREATE INDEX CONCURRENTLY')
-          .sub(/#{index_name}/, replacement_index_name)
-
-        logger.info("creating replacement index #{replacement_index_name}")
-        logger.debug("replacement index definition: #{create_replacement_index_statement}")
-
-        disable_statement_timeout do
-          connection.execute(create_replacement_index_statement)
-        end
-      end
-
-      def replacement_index_valid?
-        find_index(replacement_index_name).indisvalid
-      end
-
-      def find_index(index_name)
-        record = connection.select_one(<<~SQL)
-          SELECT
-            pg_index.indisunique,
-            pg_index.indisvalid,
-            pg_indexes.indexdef
-          FROM pg_index
-          INNER JOIN pg_class ON pg_class.oid = pg_index.indexrelid
-          INNER JOIN pg_namespace ON pg_class.relnamespace = pg_namespace.oid
-          INNER JOIN pg_indexes ON pg_class.relname = pg_indexes.indexname
-          WHERE pg_namespace.nspname = 'public'
-          AND pg_class.relname = #{connection.quote(index_name)}
-        SQL
-
-        OpenStruct.new(record) if record
-      end
-
-      def swap_replacement_index
-        replaced_index_name = constrained_index_name(REPLACED_INDEX_PREFIX)
-
-        logger.info("swapping replacement index #{replacement_index_name} with #{index_name}")
-
-        with_lock_retries do
-          rename_index(index_name, replaced_index_name)
-          rename_index(replacement_index_name, index_name)
-          rename_index(replaced_index_name, replacement_index_name)
-        end
-      end
-
-      def rename_index(old_index_name, new_index_name)
-        connection.execute("ALTER INDEX #{old_index_name} RENAME TO #{new_index_name}")
-      end
-
-      def remove_replacement_index
-        disable_statement_timeout do
-          connection.execute("DROP INDEX CONCURRENTLY IF EXISTS #{replacement_index_name}")
-        end
-      end
-
-      def with_lock_retries(&block)
-        arguments = { klass: self.class, logger: logger }
-
-        Gitlab::Database::WithLockRetries.new(arguments).run(raise_on_exhaustion: true, &block)
-      end
-    end
-  end
-end