discourse/lib/backup_restore/backup_restore.rb

197 lines
5.1 KiB
Ruby

require "backup_restore/backuper"
require "backup_restore/restorer"
module BackupRestore
class OperationRunningError < RuntimeError; end
DUMP_FILE = "dump.sql"
METADATA_FILE = "meta.json"
LOGS_CHANNEL = "/admin/backups/logs"
def self.backup!(user_id, opts={})
start! BackupRestore::Backuper.new(user_id, opts)
end
def self.restore!(user_id, opts={})
start! BackupRestore::Restorer.new(user_id, opts)
end
def self.rollback!
raise BackupRestore::OperationRunningError if BackupRestore.is_operation_running?
if can_rollback?
move_tables_between_schemas("backup", "public")
after_fork
end
end
def self.cancel!
set_shutdown_signal!
true
end
def self.mark_as_running!
$redis.setex(running_key, 60, "1")
save_start_logs_message_id
keep_it_running
end
def self.is_operation_running?
!!$redis.get(running_key)
end
def self.mark_as_not_running!
$redis.del(running_key)
end
def self.should_shutdown?
!!$redis.get(shutdown_signal_key)
end
def self.can_rollback?
backup_tables_count > 0
end
def self.operations_status
{
is_operation_running: is_operation_running?,
can_rollback: can_rollback?,
allow_restore: Rails.env.development? || SiteSetting.allow_restore
}
end
def self.logs
id = start_logs_message_id
MessageBus.backlog(LOGS_CHANNEL, id).map { |m| m.data }
end
def self.current_version
ActiveRecord::Migrator.current_version
end
def self.move_tables_between_schemas(source, destination)
User.exec_sql(move_tables_between_schemas_sql(source, destination))
end
def self.move_tables_between_schemas_sql(source, destination)
<<-SQL
DO $$DECLARE row record;
BEGIN
-- create <destination> schema if it does not exists already
-- NOTE: DROP & CREATE SCHEMA is easier, but we don't want to drop the public schema
-- ortherwise extensions (like hstore & pg_trgm) won't work anymore...
CREATE SCHEMA IF NOT EXISTS #{destination};
-- move all <source> tables to <destination> schema
FOR row IN SELECT tablename FROM pg_tables WHERE schemaname = '#{source}'
LOOP
EXECUTE 'DROP TABLE IF EXISTS #{destination}.' || quote_ident(row.tablename) || ' CASCADE;';
EXECUTE 'ALTER TABLE #{source}.' || quote_ident(row.tablename) || ' SET SCHEMA #{destination};';
END LOOP;
-- move all <source> views to <destination> schema
FOR row IN SELECT viewname FROM pg_views WHERE schemaname = '#{source}'
LOOP
EXECUTE 'DROP VIEW IF EXISTS #{destination}.' || quote_ident(row.viewname) || ' CASCADE;';
EXECUTE 'ALTER VIEW #{source}.' || quote_ident(row.viewname) || ' SET SCHEMA #{destination};';
END LOOP;
END$$;
SQL
end
DatabaseConfiguration = Struct.new(:host, :port, :username, :password, :database)
def self.database_configuration
config = Rails.env.production? ? ActiveRecord::Base.connection_pool.spec.config : Rails.configuration.database_configuration[Rails.env]
config = config.with_indifferent_access
DatabaseConfiguration.new(
config["host"],
config["port"],
config["username"] || ENV["USER"] || "postgres",
config["password"],
config["database"]
)
end
private
def self.running_key
"backup_restore_operation_is_running"
end
def self.keep_it_running
# extend the expiry by 1 minute every 30 seconds
Thread.new do
# this thread will be killed when the fork dies
while true
$redis.expire(running_key, 1.minute)
sleep 30.seconds
end
end
end
def self.shutdown_signal_key
"backup_restore_operation_should_shutdown"
end
def self.set_shutdown_signal!
$redis.set(shutdown_signal_key, "1")
end
def self.clear_shutdown_signal!
$redis.del(shutdown_signal_key)
end
def self.save_start_logs_message_id
id = MessageBus.last_id(LOGS_CHANNEL)
$redis.set(start_logs_message_id_key, id)
end
def self.start_logs_message_id
$redis.get(start_logs_message_id_key).to_i
end
def self.start_logs_message_id_key
"start_logs_message_id"
end
def self.start!(runner)
child = fork do
begin
after_fork
runner.run
rescue Exception => e
puts "--------------------------------------------"
puts "---------------- EXCEPTION -----------------"
puts e.message
puts e.backtrace.join("\n")
puts "--------------------------------------------"
ensure
begin
clear_shutdown_signal!
rescue Exception => e
puts "============================================"
puts "================ EXCEPTION ================="
puts e.message
puts e.backtrace.join("\n")
puts "============================================"
ensure
exit!(0)
end
end
end
Process.detach(child)
true
end
def self.after_fork
Discourse.after_fork
end
def self.backup_tables_count
User.exec_sql("SELECT COUNT(*) AS count FROM information_schema.tables WHERE table_schema = 'backup'")[0]['count'].to_i
end
end