discourse/lib/backup_restore.rb

217 lines
5.6 KiB
Ruby

# frozen_string_literal: true
module BackupRestore
class OperationRunningError < RuntimeError; end
VERSION_PREFIX = "v"
DUMP_FILE = "dump.sql.gz"
LOGS_CHANNEL = "/admin/backups/logs"
def self.backup!(user_id, opts = {})
if opts[:fork] == false
BackupRestore::Backuper.new(user_id, opts).run
else
start! BackupRestore::Backuper.new(user_id, opts)
end
end
def self.restore!(user_id, opts = {})
restorer = BackupRestore::Restorer.new(
user_id: user_id,
filename: opts[:filename],
factory: BackupRestore::Factory.new(
user_id: user_id,
client_id: opts[:client_id]
)
)
start! restorer
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!
Discourse.redis.setex(running_key, 60, "1")
save_start_logs_message_id
keep_it_running
end
def self.is_operation_running?
!!Discourse.redis.get(running_key)
end
def self.mark_as_not_running!
Discourse.redis.del(running_key)
end
def self.should_shutdown?
!!Discourse.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)
ActiveRecord::Base.transaction do
DB.exec(move_tables_between_schemas_sql(source, destination))
end
end
def self.move_tables_between_schemas_sql(source, destination)
<<~SQL
DO $$DECLARE row record;
BEGIN
-- create <destination> schema if it does not exists already
-- NOTE: DROP & CREATE SCHEMA is easier, but we don't want to drop the public schema
-- otherwise extensions (like hstore & pg_trgm) won't work anymore...
CREATE SCHEMA IF NOT EXISTS #{destination};
-- move all <source> tables to <destination> schema
FOR row IN SELECT tablename FROM pg_tables WHERE schemaname = '#{source}'
LOOP
EXECUTE 'DROP TABLE IF EXISTS #{destination}.' || quote_ident(row.tablename) || ' CASCADE;';
EXECUTE 'ALTER TABLE #{source}.' || quote_ident(row.tablename) || ' SET SCHEMA #{destination};';
END LOOP;
-- move all <source> views to <destination> schema
FOR row IN SELECT viewname FROM pg_views WHERE schemaname = '#{source}'
LOOP
EXECUTE 'DROP VIEW IF EXISTS #{destination}.' || quote_ident(row.viewname) || ' CASCADE;';
EXECUTE 'ALTER VIEW #{source}.' || quote_ident(row.viewname) || ' SET SCHEMA #{destination};';
END LOOP;
END$$;
SQL
end
DatabaseConfiguration = Struct.new(:host, :port, :username, :password, :database)
def self.database_configuration
config = ActiveRecord::Base.connection_pool.spec.config
config = config.with_indifferent_access
# credentials for PostgreSQL in CI environment
if Rails.env.test?
username = ENV["PGUSER"]
password = ENV["PGPASSWORD"]
end
DatabaseConfiguration.new(
config["backup_host"] || config["host"],
config["backup_port"] || config["port"],
config["username"] || username || ENV["USER"] || "postgres",
config["password"] || 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
Discourse.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!
Discourse.redis.set(shutdown_signal_key, "1")
end
def self.clear_shutdown_signal!
Discourse.redis.del(shutdown_signal_key)
end
def self.save_start_logs_message_id
id = MessageBus.last_id(LOGS_CHANNEL)
Discourse.redis.set(start_logs_message_id_key, id)
end
def self.start_logs_message_id
Discourse.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
DB.query_single("SELECT COUNT(*) AS count FROM information_schema.tables WHERE table_schema = 'backup'").first.to_i
end
end