A step by step guide helps installing a RabbitMQ server and testing it before MariaDB MaxScale integration.
New plugin filter and a message consumer application need to be compiled and linked with an external C library, RabbitMQ-c, that provides AMQP protocol integration. Custom configuration, with TCP/IP and Queue parameters, is also detailed here. The software install setup provides RPM and DEB packaging and traditional compilation steps.
On Centos 6.5 using fedora / RHEL rpm get the rpm from http://www.rabbitmq.com/
rabbitmq-server-3.3.4-1.noarch.rpm
Please note, before installing RabbitMQ, you must install Erlang.
Example:
yum install erlang
Package erlang-R14B-04.3.el6.x86_64 already installed and latest version
Install the packages using your distribution's package manager and start the server:
yum install rabbitmq-server-3.3.4-1.noarch.rpm
systemctl start rabbitmq-server.service
To configure your RabbitMQ server, please refer to the RabbitMQ website: [http://www.rabbitmq.com/](http://www.rabbitmq.com/ RabbitMQ website).
rabbitmqctl is a command line tool for managing a RabbitMQ broker. It performs all actions by connecting to one of the broker's nodes.
rabbitmqctl list_queues
rabbitmqctl list_queues | list_exchanges| cluster_status | list_bindings | list_connections | list_consumers | status
Example output:
[root@maxscale-02 MaxScale]# rabbitmqctl status
Status of node 'rabbit@maxscale-02' ...
[{pid,12251},
{running_applications,[{rabbit,"RabbitMQ","3.3.4"},
{os_mon,"CPO CXC 138 46","2.2.7"},
{xmerl,"XML parser","1.2.10"},
{mnesia,"MNESIA CXC 138 12","4.5"},
{sasl,"SASL CXC 138 11","2.1.10"},
{stdlib,"ERTS CXC 138 10","1.17.5"},
{kernel,"ERTS CXC 138 10","2.14.5"}]},
{os,{unix,linux}},
{erlang_version,"Erlang R14B04 (erts-5.8.5) [source] [64-bit] [smp:2:2] [rq:2] [async-threads:30] [kernel-poll:true]\n"},
...
{listeners,[{clustering,25672,"::"},{amqp,5672,"::"}]},
...
...done.
[root@maxscale-02 MaxScale]# rabbitmqctl list_bindings
Listing bindings ...
x1 exchange q1 queue k1 []
...done.
Interaction with the server may require stop & reset at some point:
rabbitmqctl stop_app
rabbitmqctl reset
rabbitmqctl start_app
The selected library for MariaDB MaxScale integration of RabbitMQ is: [https://github.com/alanxz/rabbitmq-c](https://github.com/alanxz/rabbitmq-c RabbitMQ-C)
To compile the RabbitMQ-C libraries manually:
git clone https://github.com/alanxz/rabbitmq-c.git
cd rabbitmq-c
cmake -DCMAKE_INSTALL_PREFIX=/usr .
make
make install
Please note, this will install the packages to /usr. If you do not wish to install them to this location, provide a different value for the CMAKE_INSTALL_PREFIX variable.
Check how to configure your distribution for the EPEL repository: [https://fedoraproject.org/wiki/EPEL](https://fedoraproject.org/wiki/EPEL EPEL)
Configure your repositories and install the software:
yum install librabbitmq.x86_64
you might also like to install:
librabbitmq-tools.x86_64, librabbitmq-devel.x86_64
Please note you may also install the rabbitmq server from the EPEL repository:
yum install rabbitmq-server
The required library librabbitmq-c is now installed and we continue with basic operations with amqp_* tools, located in the examples/ folder of the build directory, testing client server interaction.
Please note, those example applications may not be included in the RPM library packages.
[root@maxscale-02 examples]# ./amqp_exchange_declare
Usage: amqp_exchange_declare host port exchange exchangetype
Declare the exchange:
[root@maxscale-02 examples]# ./amqp_exchange_declare 127.0.0.1 5672 foo direct
[root@maxscale-02 examples]# ./amqp_listen
Usage: amqp_listen host port exchange bindingkey
Start the listener:
[root@maxscale-02 examples]# ./amqp_listen 127.0.0.1 5672 foo k1 &
[root@maxscale-02 examples]# ./amqp_sendstring
Usage: amqp_sendstring host port exchange routingkey messagebody
[root@maxscale-02 examples]# ./amqp_sendstring 127.0.0.1 5672 foo k1 “This is a new message”
... and watch the listener output
Delivery 1, exchange foo routingkey k1
Content-type: text/plain
The new filter needs to be configured in maxscale.cnf.
[Test-Service]
type=service
router=readconnroute
router_options=slave
servers=server1,server2,server3,server5,server4
user=massi
password=massi
filters=MQ
[MQ]
type=filter
module=mqfilter
exchange=x1
key=k1
queue=q1
hostname=127.0.0.1
port=5672
logging_trigger=all
Logging triggers define whether to log all or a subset of the incoming queries using these options:
# log only some elements or all
logging_trigger=[all,source,schema,object]
# Whether to log only SELECT, UPDATE, INSERT and DELETE queries or all possible queries
logging_log_all=true|false
# Log only when any of the trigger parameters match or only if all parameters match
logging_strict=true|false
# specify objects
logging_object=mytable,another_table
# specify logged users
logging_source_user=testuser,testuser
# specify source addresses
logging_source_host=127.0.0.1,192.168.10.14
# specify schemas
logging_schema=employees,orders,catalog
Example:
logging_trigger=object,schema,source
logging_strict=false
logging_log_all=false
logging_object=my1
logging_schema=test
logging_source_user=maxtest
The logging result of the example is:
if user maxtest does something, it's logged
and all queries in test schema are logged
anything targeting my1 table is logged
SELECT NOW(), SELECT MD5(“xyz)” are not logged
Please note that if we want to log only the user ‘maxtest’ accessing the schema ‘test’ with target ‘my1’ the option logging_strict must be set to TRUE and if we want to include those selects without schema name the option logging_log_all must be set to TRUE.
The mqfilter logs into the MariaDB MaxScale TRACE log information about the matched logging triggers and the message delivering:
2014 09/03 06:22:04 Trigger is TRG_SOURCE: user: testuser = testuser
2014 09/03 06:22:04 Trigger is TRG_SCHEMA: test = test
2014 09/03 06:22:04 Trigger is TRG_OBJECT: test.t1 = t1
2014 09/03 06:22:04 Routing message to: 127.0.0.1:5672 / as guest/guest, exchange: x1<direct> key:k1 queue:q1
The consumer application needs to be configured as well:
#The options for the consumer are:
#hostname RabbitMQ hostname
#port RabbitMQ port
#vhost RabbitMQ virtual host
#user RabbitMQ username
#passwd RabbitMQ password
#queue Name of the queue to use
#dbserver SQL server name
#dbport SQL server port
#dbname Name of the database to use
#dbuser SQL server username
#dbpasswd SQL server password
#logfile Message log filename
[consumer]
hostname=127.0.0.1
port=5672
vhost=/
user=guest
passwd=guest
queue=q1
dbserver=127.0.0.1
dbport=3308
dbname=mqpairs
dbuser=xxx
dbpasswd=yyy
We may probably need to modify LD_LIBRARY_PATH before launching ‘consumer’:
# export LD_LIBRARY_PATH=/packages/rabbitmq-c/rabbitmq-c/librabbitmq:/packages/mariadb_client-2.0.0-Linux/lib/mariadb:/usr/lib64
and finally we can launch it:
# ./consumer
If the consumer.cnf file is not in the same directory as the binary file is, you can provide the location of the folder that it is in by passing it the -c flag followed by the path:
# ./consumer -c path/to/file
and start MariaDB MaxScale as well
Assuming that MariaDB MaxScale and the message consumer are successfully running let’s connect to the service with an active mqfilter:
[root@maxscale-02 MaxScale]# mysql -h 127.0.0.1 -P 4506 -uxxx -pyyy
...
MariaDB [(none)]> select RAND(3), RAND(5);
+--------------------+---------------------+
| RAND(3) | RAND(5) |
+--------------------+---------------------+
| 0.9057697559760601 | 0.40613597483014313 |
+--------------------+---------------------+
1 row in set (0.01 sec)
…
MariaDB [(none)]> select RAND(3544), RAND(11);
we can check the consumer output in the terminal where it was started:
--------------------------------------------------------------
Received: 1409671452|select @@version_comment limit ?
Received: 1409671452|Columns: 1
...
Received: 1409671477|select RAND(?), RAND(?)
Received: 1409671477|Columns: 2
We query now the database for the content collected so far:
MariaDB [(none)]> use mqpairs;
Database changed
MariaDB [mqpairs]> select * from pairs;
+-------------------------------------+----------------------------------+------------+---------------------+---------------------+---------+
| tag | query | reply | date_in | date_out | counter |
+-------------------------------------+----------------------------------+------------+---------------------+---------------------+---------+
| 006c006d006e006f007000710072007374 | select @@version_comment limit ? | Columns: 1 | 2014-09-02 11:14:51 | 2014-09-02 11:26:38 | 3 |
| 00750076007700780079007a007b007c7d | SELECT DATABASE() | Columns: 1 | 2014-09-02 11:14:56 | 2014-09-02 11:27:06 | 3 |
| 007e007f00800081008200830084008586 | show databases | Columns: 1 | 2014-09-02 11:14:56 | 2014-09-02 11:27:06 | 3 |
| 008700880089008a008b008c008d008e8f | show tables | Columns: 1 | 2014-09-02 11:14:56 | 2014-09-02 11:27:06 | 3 |
| 0090009100920093009400950096009798 | select * from mqpairs.pairs | Columns: 6 | 2014-09-02 11:15:00 | 2014-09-02 11:27:00 | 12 |
| 00fc00fd00fe00ff0100010101020103104 | select NOW() | Columns: 1 | 2014-09-02 11:24:23 | 2014-09-02 11:24:23 | 1 |
| 01050106010701080109010a010b010c10d | select RAND(?), RAND(?) | Columns: 2 | 2014-09-02 11:24:37 | 2014-09-02 11:24:37 | 1 |
+-------------------------------------+----------------------------------+------------+---------------------+---------------------+---------+
7 rows in set (0.01 sec)
The filter send queries to the RabbitMQ server in the canonical format, i.e select RAND(?), RAND(?). The queries Message Queue Consumer application gets from the server are stored with a counter that quickly shows how many times that normalized query was received:
| 01050106010701080109010a010b010c10d | select RAND(?), RAND(?) | Columns: 2 | 2014-09-02 11:24:37 | 2014-09-02 11:29:15 | 3 |