aec1310c52
The tee, qlafilter, namedserverfilter and topfilter now support the same filter options: case, ignorecase and extended. The extended filter option enables the Extended Regular Expression syntax for the filters which is used when matching queries.
2.8 KiB
Named Server Filter
Overview
The namedserverfilter is a filter module for MaxScale which is able to route queries to servers based on regular expression matches.
Configuration
The configuration block for the Named Server filter requires the minimal filter options in it’s section within the maxscale.cnf file, stored in /etc/maxscale.cnf.
[NamedServerFilter]
type=filter
module=namedserverfilter
match=some string
server=server2
[MyService]
type=service
router=readwritesplit
servers=server1,server2
user=myuser
passwd=mypasswd
filters=NamedServerFilter
Filter Options
The named server filter accepts the following options.
| Option | Description |
|---|---|
| ignorecase | Use case-insensitive matching |
| case | Use case-sensitive matching |
| extended | Use extended regular expression syntax (ERE) |
To use multiple filter options, list them in a comma-separated list.
options=case,extended
Filter Parameters
The named server filter requires two mandatory parameters to be defined.
match
A parameter that can be used to match text in the SQL statement which should be replaced.
match=TYPE[ ]*=
If the filter option ignorecase is used all regular expressions are evaluated with the option to ignore the case of the text, therefore a match option of select will match both type, TYPE and any form of the word with upper or lowercase characters.
server
This is the server where matching queries will be router. The server should be in use by the service which uses this filter.
server=server2
source
The optional source parameter defines an address that is used to match against the address from which the client connection to MaxScale originates. Only sessions that originate from this address will have the match and replacement applied to them.
source=127.0.0.1
user
The optional user parameter defines a user name that is used to match against the user from which the client connection to MaxScale originates. Only sessions that are connected using this username will have the match and replacement applied to them.
user=john
Examples
Example 1 - Route queries targeting a specific table to a server
This will route all queries matching the regular expression *from *users to the server named server2. The filter will ignore character case in queries.
A query like SELECT * FROM users would be routed to server2 where as a query like SELECT * FROM accounts would be routed according to the normal rules of the router.
[NamedServerFilter]
type=filter
module=namedserverfilter
match= *from *users
options=ignorecase
server=server2
[MyService]
type=service
router=readwritesplit
servers=server1,server2
user=myuser
passwd=mypasswd
filters=NamedServerFilter