Re: More on access control for LAS

["Jennifer M. Adams" <jma@xxxxxxxxxxxxx>]

Hi, Jon --

Yes, GrADS does employ environmental variables to look for
data sets and script files, but in my XML file describing
this data, I give it a full path name so it shouldn't have
to go a-huntin'. That path name also appears in the GrADS
script that custom.pl writes out. 

<datasets>
  <avn_model_output 
    name="AVN Forecast Model Output"
    url="file:/var/homes/wxdata/dodsdata/avn00.07may01.ctl"
    js="TestServer">
    <variables>
    ...
    </variables>
  </avn_model_output>
</datasets>

--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


Jonathan Callahan wrote:
> 
> 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