Re: More on access control for LAS

[Jonathan Callahan <callahan@xxxxxxxxxxxxx>]

Jennifer,

When using Ferret as the back end there is a file named Ferret_config.pl
which sets various Ferret environment variables including FER_DATA. 
Does GRADS have a similar way of telling it where to look for data? 
Your code to run GRADS should set the necessary environment variables to
run GRADS.  I imagine the default is to look in the current directory
but it sounds like the GRADS equivalent of FER_DATA exists if GRADS can
find data when you run it stand alone.

Remember, the environment variables used by GRADS when run from LAS are
those it gets from the user profile for the web server, not your own.

-- Jon


"Jennifer M. Adams" wrote:
> 
> Dear Experts,
> 
> My GrADS-enabled version of LAS is working (thanks, Joe!)
> and I am getting ready to serve up some real-time forecast
> data in GRIB format. Here's the thing: if the data set I'm
> serving is not located underneath the $LASROOT directory,
> then the LAS's execution of GrADS can't see the file and I
> can't open it, even for read-only purposes. If I execute
> GrADS outside the LAS and run the very same script that the
> LAS tried to run, it works just fine. When I copied the data
> set so it would be underneath $LASROOT, then the LAS worked
> perfectly.
> 
> It smells like an apache configuration problem, and I found
> a brief exchange on a similar issue in the email archives.
> Steve Cousins referred to the Directory Tag in the
> httpd.conf file, and although his solution was for
> *restricting* access to certain data directories, I think
> the implementation is probably similar. Here's what we've
> added, where /var/homes/wxdata/dodsdata is the top directory
> where the GRIB data is located:
> 
> <Directory "/var/homes/wxdata/dodsdata">
>    Options Indexes Includes FollowSymLinks
> </Directory>
> 
> Unfortunately, this change made no difference to the LAS,
> even after re-configuring and shift-reloading. I'd like the
> LAS to access this directory and anything underneath it. The
> data files there are all readable by everyone (i.e.,
> -rw-rw-r--) Can anyone tell me what would be the right way
> to configure it?
> 
> Respectfully submitted,
> Jennifer
> 
> --
> ----------------------------------------
> Jennifer Miletta Adams
> Center for Ocean-Land-Atmosphere Studies
> 4041 Powder Mill Road, Suite 302
> Calverton, MD 20705-3106
> Phone: (301)902-1278 or (301)595-7000
> Fax:   (301)595-9793
> Email: jma@cola.iges.org