[augeas-devel] RFC: Augeas Check function

[Bryan Kearney]

David Lutterkort wrote:
> On Fri, 2009-01-09 at 13:34 -0500, Bryan Kearney wrote:
>> For the puppet plugin, I would like to know if a change will be made 
>> before making it. Basically, to understand how many files would be 
>> effected by an aug_save call.
>>
>> Can you please look at the latest commit here:
>>
>> http://github.com/bkearney/augeas/tree/master
>>
>> I added an aug_check method to perform this. I opted to replicate the 
>> aug_save and tree_save methods instead of having alot of 
>> if_actually_saving logic in the tree_save method. I did some simple 
>> tests and it seems to work. It may be a odd edge case, but it would make 
>>   the puppet plugin alot easier :)
> 
> This kinda overlaps with another change I've been meaning to make: make
> it possible to change how things are saved at runtime - right now, you
> need to decide that when you call aug_init by passing one of the
> AUG_SAVE_* flags. 
> 
> I've been meaning to change that so that you can do something like
>   set /augeas/save overwrite
>   save
>   .. more changes to the tree ..
>   set /augeas/save backup
>   save
> so that the first batch of changes just overwrites existing files, and
> the second also saves .augsave files.
> 
> With that model, we'd add another option for /augeas/save, say 'check'
> or 'none' and do what your aug_check call does. With that, we wouldn't
> need to add another API call, and the implementation would just be a few
> additional lines in aug_save and tree_save.
> 
> What do you think about approaching it that way ?


I would be fine with that.. as long as
set /augeas/save noop

still returns the number of files which would be changed.

-- bk