---
name: "queue_mover2"
section: "1"
platform: "linux"
package: "skytools"
version: "2.1.13-2"
release: "Debian 7 (Wheezy)"
platforms: ["linux"]
url: "https://new.carta.tech/queue_mover2"
---

# queue\_mover2(1)

PgQ consumer that copies data from one queue to another.

## NAME

queue\_mover - PgQ consumer that copies data from one queue to another.

## SYNOPSIS

```
queue_mover.py [switches] config.ini
```

## DESCRIPTION

queue\_mover is PgQ consumer that transports events from source queue into target queue. One use case is when events are produced in several databases then queue\_mover is used to consolidate these events into single queue that can then be processed by consumers who need to handle theses events. For example in case of patitioned databases it’s convenient to move events from each partition into one central queue database and then process them there. That way configuration and dependancies of partiton databases are simpler and more robust. Another use case is to move events from OLTP database to batch processing server.

Transactionality: events will be inserted as one transaction on target side. That means only batch\_id needs to be tracked on target side.

## QUICK-START

Basic PgQ setup and usage can be summarized by the following steps:

 1\. PgQ must be installed both in source and target databases. See pgqadm man page for details.

 2\. Target database must also have pgq\_ext schema installed. It is used to keep sync between two databases.

 3\. Create a queue\_mover configuration file, say qmover\_sourceq\_to\_targetdb.ini

 4\. create source and target queues

```
$ pgqadm.py sourcedb_ticker.ini create <srcqueue>
$ pgqadm.py targetdb_ticker.ini create <dstqueue>
```

 5\. launch queue mover in daemon mode

```
$ queue_mover.py -d qmover_sourceq_to_targetdb.ini
```

 6\. start producing and consuming events

## CONFIG

### Common configuration parameters

job\_name

Name for particulat job the script does. Script will log under this name to logdb/logserver. The name is also used as default for PgQ consumer name. It should be unique.

pidfile

Location for pid file. If not given, script is disallowed to daemonize.

logfile

Location for log file.

loop\_delay

If continuisly running process, how long to sleep after each work loop, in seconds. Default: 1.

connection\_lifetime

Close and reconnect older database connections.

log\_count

Number of log files to keep. Default: 3

log\_size

Max size for one log file. File is rotated if max size is reached. Default: 10485760 (10M)

use\_skylog

If set, search for \[./skylog.ini, ~/.skylog.ini, /etc/skylog.ini\]. If found then the file is used as config file for Pythons logging module. It allows setting up fully customizable logging setup.

### Common PgQ consumer parameters

pgq\_queue\_name

Queue name to attach to. No default.

pgq\_consumer\_id

Consumers ID to use when registering. Default: %(job\_name)s

### queue\_mover parameters

src\_db

Source database.

dst\_db

Target database.

dst\_queue\_name

Target queue name.

### Example config file

```
[queue_mover]
job_name = eventlog_to_target_mover
src_db = dbname=sourcedb
dst_db = dbname=targetdb
pgq_queue_name = eventlog
dst_queue_name = copy_of_eventlog
pidfile = log/%(job_name)s.pid
logfile = pid/%(job_name)s.log
```

## COMMAND LINE SWITCHES

Following switches are common to all skytools.DBScript-based Python programs.

\-h, --help

show help message and exit

\-q, --quiet

make program silent

\-v, --verbose

make program more verbose

\-d, --daemon

make program go background

Following switches are used to control already running process. The pidfile is read from config then signal is sent to process id specified there.

\-r, --reload

reload config (send SIGHUP)

\-s, --stop

stop program safely (send SIGINT)

\-k, --kill

kill program immidiately (send SIGTERM)

## BUGS

Event ID is not kept on target side. If needed is can be kept, then event\_id seq at target side need to be increased by hand to inform ticker about new events.