nALFS2 Daemon and Front Split

Kevin P. Fleming kpfleming at
Wed Aug 11 20:42:36 PDT 2004

James Robertson wrote:

> What "end" makes sure the profile is valid?  I would think back-end
> daemon.

Validation (true validation, against the schema) will likely be done 
outside nALFS completely, as it is now. I don't have any opposition to 
building a validation mechanism into the frontend, but I wouldn't want 
it to run every time a profile is loaded, or it will slow down the 
client quite a bit.

   Are there mechanism to go a "test" run before actual run to see
> if there are any errors?  I was thinking for things like copy.  Make
> sure that the files asked for are present and the checksums are valid
> before actually running the build.

This is actually very, very hard to do. Those {copy} elements could be 
inside a stage that does a chroot(), they could be copying files that 
don't exist until the steps before them have been run, they could be 
copying files that are only accessible under a different userid, etc.

I believe the direction we will need to go for any type of "pre-run" 
checking will involve enhancing the profile syntax to make elements able 
to explicitly specify what things to do during the "pre-run" step. I 
just can't see any way that nALFS (or any ALFS tool) could somehow 
"figure out" what to check up front.

More information about the alfs-discuss mailing list