Update sections

10 Jul 2013

      Update sections in 3.0 are considerably more powerful than 2.x.x

In addition to being able to override lists on an attribute by attribute basis, e.g:

update {
	request:foo = 'bar'
}

You can also perform full list copies:

update {
	request: += &reply:
}

Filtered list copies (all instance of attribute in a list)

update {
	request: += &reply:foo
}

Reference attributes:

update {
	request:foo += &reply:foo
}

and perform both types of program execution:

update {
	request:foo := `<my program>` # foo is assigned the output of my program
}

update {
	request: := `<my program>` # any VALUE_PAIRs returned by my program are added to the request list
}

Update sections may now also return fail.

(0)   update  {
(0) Executing: "/tmp/foo %{User-Name}"
(0) 	expand: "%{User-Name}" -> 'foo'
(0) Program returned code (2): Failed to execute "/tmp/foo": No such file or directory
(0) ERROR: Failed to execute "/tmp/foo": No such file or directory
(0)   } # update  = fail

In which case subsequent statements are not executed. As with modules failure this can be checked with if (fail).

Update sections are no longer atomic as a whole. But individual statements are. That is if a statement fails, all VALUE_PAIRs created up to the point of the failure are discarded.

We may be able to restore atomicity of update sections once sets and lists are implemented in 3.1. If you absolutely require it in 3.0 you can wrap each statement in it's own update section and check for failure.

-Arran

Arran Cudbard-Bell <a.cudbardb@freeradius.org>
FreeRADIUS Development Team