perl-ldap-dev

Testing for existence of attributes

[Craig R. <cra...@ep...>]

Net::LDAP experts,

I have a problem that has been bugging me for ages.

I am trying to see if an email address exists within our organization. The =
following is a snippet of code which returns the DN of an entry which match=
es a certain email address:

use Net::LDAP;
$ldap =3D Net::LDAP->new("bartfarst.env.qld.gov.au") or die "$@";
$DS_mesg =3D $ldap->search(base =3D> "o=3Denv,st=3Dqld,c=3Dau",filter =3D> =
"mail=3Dcraig.robinson\@epa.qld.gov.au");
$DS_entry =3D $DS_mesg->shift_entry;
$DS_dn =3D $DS_entry->dn;
print "DN: $DS_dn\n";
$ldap->unbind;

It works great if the email address exists. BUT if the email address does n=
ot exist, I get the following error message:

"Can't call method "dn" on an undefined value at test.pl line 5."

I would prefer a message like:

"Sorry Craig, there is no entry which has this email address"

Does anyone know of a <simple> way of finding out if an entry containing a =
specific attribute exists, or better still, DOES NOT EXIST??

(If you would like to reply off-list, I will summarise and post summary bac=
k to list.)

Cheers, Craig

Craig Robinson
Environmental Protection Agency
Tel: (07) 3006 4629     Fax: (07) 3247 6534
Email: cra...@ep...

Visit us at: http://www.epa.qld.gov.au 

Re: Testing for existence of attributes

[Chris R. <chr...@me...>]

On 14/8/02 7:23 am, Craig Robinson <cra...@ep...> wrote:

> Net::LDAP experts,
> 
> I have a problem that has been bugging me for ages.
> 
> I am trying to see if an email address exists within our organization. The
> following is a snippet of code which returns the DN of an entry which matches
> a certain email address:
> 
> use Net::LDAP;
> $ldap = Net::LDAP->new("bartfarst.env.qld.gov.au") or die "$@";
> $DS_mesg = $ldap->search(base => "o=env,st=qld,c=au",filter =>
> "mail=craig.robinson\@epa.qld.gov.au");
> $DS_entry = $DS_mesg->shift_entry;
> $DS_dn = $DS_entry->dn;
> print "DN: $DS_dn\n";
> $ldap->unbind;
> 
> It works great if the email address exists. BUT if the email address does not
> exist, I get the following error message:
> 
> "Can't call method "dn" on an undefined value at test.pl line 5."
> 
> I would prefer a message like:
> 
> "Sorry Craig, there is no entry which has this email address"
> 
> Does anyone know of a <simple> way of finding out if an entry containing a
> specific attribute exists, or better still, DOES NOT EXIST??

This is not entirely what you've asked for, but it solves the problem for
the above scriptlet.

$DS_mesg = $ldap->search(...);
if ($DS_mesg->count() != 1) {
    print "Cannot find one entry with this email address\n";
} else {
    $DS_entry = $DS_mesg->shift_entry;
    ...
}

Cheers,

Chris