Compliance objects library

Individual objects

The following objects are shipped with the OpenSVC agent, in var/compliance/com.opensvc/.

We recommend to track your own set of objects in your modules project, for example in a com.mycorp/ folder, so that upgrading the agent can not cause regressions in the compliance framework.

You can create your own objects and associated forms, and you are welcome to contribute them upstream to enrich this library.

Combining objects in modules

The following examples illustrate how combining the compliance objects described in the previous chapter can solve complex needs.

Variable substitution

Variable substitution is a convience feature of most compliance objects, allowing to define a rule once and contextualize only a part of its content.

For example, if you need to distribute a startup launcher script to a mixed SuSE and Red Hat server set, you can define two file-class rules like this:

{
  "path": "/etc/init.d/mylauncher",
  "perm"! "755",
  "user": "root",
  "group": "root",
  "content": "some very long content"
}

And:

{
  "path": "/sbin/init.d/mylauncher",
  "perm"! "755",
  "user": "root",
  "group": "root",
  "content": "some very long content"
}

Here, the two rules are nearly identical. Only the init.d path changes. When you need to change another key value, you have to edit all those nearly identical rules, which is an error-prone process. In this case, it is pertinent to define this rule only once, using variable substitution for the init.d path:

{
  "path": "%%ENV:INIT_D%%",
  "perm"! "755",
  "user": "root",
  "group": "root",
  "content": "some very long content"
}

For the substitution to work, you have to define contextually the INIT_D values to /sbin/init.d or /etc/init.d. This can be naturally designed as raw-class rules in per-operating system contextual rulesets, or even hard-coded in the module code before calling the files object.

The former method is preferred, as the INIT_D definitions can beneficit other modules.

A lot of minor differences between operating systems are candidate to be abstracted that way. To name a few :

  • the root account primary group : root on most unices, sys on HP-UX

  • the preferred shell is often bash on Linux, and ksh on other unices

  • the preferred filesystem to format with is surely a per operating system, and often a per release, preference