MySQL filter

In this example, we show how the MySQL filter can be used with the Envoy proxy.

The Envoy proxy configuration includes a MySQL filter that parses queries and collects MySQL-specific metrics.

Step 1: Build the sandbox

Change to the examples/mysql directory.

Build and start the containers.

Terminal 1

$ pwd
envoy/examples/mysql
$ docker-compose pull
$ docker-compose up --build -d
$ docker-compose ps

    Name                   Command               State                             Ports
----------------------------------------------------------------------------------------------------
mysql_mysql_1   docker-entrypoint.sh mysqld      Up      3306/tcp
mysql_proxy_1   /docker-entrypoint.sh /bin       Up      10000/tcp, 1999/tcp, 0.0.0.0:8001->8001/tcp

Step 2: Issue commands using mysql

Use mysql to issue some commands and verify they are routed via Envoy. Note that the current implementation of the protocol filter was tested with MySQL v5.7. It may, however, not work with other versions of MySQL due to differences in the protocol implementation, but it won’t affect normal progress of client-server communication.

Terminal 1

$ docker run --rm -it --network mysql_default mysql:5.7 mysql -h proxy -P 1999 -u root --skip-ssl
... snip ...

mysql> CREATE DATABASE test;
Query OK, 1 row affected (0.00 sec)

mysql> USE test;
Database changed
mysql> CREATE TABLE test ( text VARCHAR(255) );
Query OK, 0 rows affected (0.01 sec)

mysql> SELECT COUNT(*) FROM test;
+----------+
| COUNT(*) |
+----------+
|        0 |
+----------+
1 row in set (0.01 sec)

mysql> INSERT INTO test VALUES ('hello, world!');
Query OK, 1 row affected (0.00 sec)

mysql> SELECT COUNT(*) FROM test;
+----------+
| COUNT(*) |
+----------+
|        1 |
+----------+
1 row in set (0.00 sec)

mysql> exit
Bye

Step 3: Check egress stats

Check egress stats were updated.

Terminal 1

$ curl -s "http://localhost:8001/stats?filter=egress_mysql"
mysql.egress_mysql.auth_switch_request: 0
mysql.egress_mysql.decoder_errors: 0
mysql.egress_mysql.login_attempts: 1
mysql.egress_mysql.login_failures: 0
mysql.egress_mysql.protocol_errors: 0
mysql.egress_mysql.queries_parse_error: 2
mysql.egress_mysql.queries_parsed: 7
mysql.egress_mysql.sessions: 6
mysql.egress_mysql.upgraded_to_ssl: 0

Step 4: Check TCP stats

Check TCP stats were updated.

Terminal 1

$ curl -s "http://localhost:8001/stats?filter=mysql_tcp"
tcp.mysql_tcp.downstream_cx_no_route: 0
tcp.mysql_tcp.downstream_cx_rx_bytes_buffered: 0
tcp.mysql_tcp.downstream_cx_rx_bytes_total: 446
tcp.mysql_tcp.downstream_cx_total: 1
tcp.mysql_tcp.downstream_cx_tx_bytes_buffered: 0
tcp.mysql_tcp.downstream_cx_tx_bytes_total: 677
tcp.mysql_tcp.downstream_flow_control_paused_reading_total: 0
tcp.mysql_tcp.downstream_flow_control_resumed_reading_total: 0
tcp.mysql_tcp.idle_timeout: 0
tcp.mysql_tcp.max_downstream_connection_duration: 0
tcp.mysql_tcp.upstream_flush_active: 0
tcp.mysql_tcp.upstream_flush_total: 0