Re: Schema support

[<mi...@st...>]

Hans Aschauer wrote:
> On Wednesday, 3. April 2002 16:37, you wrote:
> 
>>Hans Aschauer wrote:
> 
>> > * The class rootDSESchema (looking for a better name...), which
>> > takes an initialize()'d and simple_bind_s()'ed ldap object.
>>
>> [..] simply let the
>>application pass in a instance of ldap.LDAPObject and solely do the
>>search_s() calls within your class.
> 
> Ooops, that was exactly what I meant. Just pass an initialized and boud 
> ldap object.

Sorry, misread your phrase.

>>BTW: Theoretically the sub schema sub entry can be different in each
>>part of the DIT.
> 
> You write of this possibility as a theoretical one. Do you know of any 
> ldap server that implements this?

No I don't know one. Hmm, I have to check database configuration in Netscape 
and iPlanet DS again. But applications have to be prepared for it.

> Maybe one should not automatically query the schema entries for every 
> branch of the DIT, but only at "important" branches.

Now the really exciting questions is how you distinguish the "important" 
branches. ;-)

IMHO efficient applications should request the DN of the sub schema sub 
entry by requesting attribute subschemaSubentry of current DN each and every 
time. If that points to a sub schema sub entry already parsed the cached 
schema instance can be used.

> If there exists no 
> schema description at the desired level of the tree, the closest one is 
> aquired (in Zopista speach) by climbing down the tree toward its root.

I'm pretty sure there are situations where tree climbing does not work. 
Don't try to be clever. Most times it does not work out. Anyway we should 
review RFC 2251, section 3.2.2 for that more closely.

BTW: There could be also these attributes in sub schema sub entry: 
matchingRuleUse, dITStructureRules, dITContentRules and nameForms.
I know OpenLDAP 2 server does not implement any of these. Does the schema 
parser in OpenLDAP 2 libs handle any of these?

Ciao, Michael.