complex data structures?
Grzegorz Marszałek
I'm writting system for managing our customers' networks. Each network
could have diffirent options turned on - ie.: backup server, or mail
server, or windows clients management, samba server etc. etc. I wrote
small ui in ruby on rails, which allows technincas just click to
provide some new functionality, or to configure it. To "glue" db with
puppet using external node script.
My question is: how you handle complex data structures in such a
situation? Simple example is: backup. You have to say what to backup
(host + path) and how to backup it (schedule, pools etc. - bacula
stuff). And you REALLY need those data together to generate config
file for backup system.
Another example: dhcp server. You have to pull from db mac, ip address
and hostname - and you build dhcpd.conf with host definitions.
Another example: iptables rules. You get data from db about what to
block/allow. And you build some chains in iptables based on this data
Another example: wpkg configuration. You need to know what hosts
should be configured, what profiles should be attached to those hosts,
and what packages should be attached for each profile.
Etc. etc.
Each time you have the same pattern - you have to in some way get data
from some kind of database (mysql, ldap, .csv files - whatever!) and
then you have to use those data together, as kind of object, or
structure, in manifests and templates.
Currently I do this in this way:
* external nodes script get data out of db
* wherever I need "complex" data - this scirpts setup variable with
YAML data inside
* if I need to use those data:
* in manifests - I have custom function, where I give variable with
YAML data as 1 parameter, and then some kind of ruby expression to get
data out of YAML. Function just converts YAML to ruby data structure
and then evals given expression to get data. Output should always be
either string, or array of strings. Then I can use this data (esp.
arrays) in puppet manifests, ie.: to create many files based on db
content.
* in templates - it's very simillar, but I still haven't figured out
how to use custom functions in templates - so I just require yaml
module, convert YAML to ruby data structure and use that inside
template (after all - it's just ruby there :),
Good thing in this solution is - it works. Bad thing - it's very
fragile...
So how you people do things like that? Are they better way to do this?
What they are?
Bye,
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Grzegorz Marszałek
gr...@post.pl