Anyone know of a JCA impl for JNDI access. Specifically for LDAP, but broader JNDI support would be cool.

Or even just a generically transactional-aware JNDI driver?

Steve,



Did you find anything on this? Is this related to creating an LDAP persister?

Regards,
Chris

That was one of the thoughts...

However, I was never able to find anything regarding generic transactional access to an LDAP or JNDI directory.

There is none: LDAP is a "I hope it works" kind of datastore, ie. it is really bad.

Exactly. The best I was ever able to find was "bridge" technologies. These came in two flavors:
1) Back you LDAP structure with a RDBMS;
2) Expose your RDBMS as an LDAP structure.

There were even some JDBC drivers for LDAP servers.

But you are correct. Plain old LDAP servers are of course tuned for read operations, but I guess I was thinking that that did not have to mean untransactional. But that seems to be the case...

The funny part is: I was really involved in some LDAP systems some years ago and everyone believed that they are "optimized for read". Someone made a benchmark (sorry, long lost) and found out that this is not true: Available LDAP systems (not only open source) where extremely slow with a medium size dataset. He then started to implement an LDAP directory server from scratch and he got some decent results (http://www.fefe.de/tinyldap/).

Still, LDAP is mostly marketing, and without the support of some email clients and management tools, LDAP would already have gone the way of all ad-hoc technical "inventions".

I think we all agree LDAP provides a limited directory view of persistent data, supposedly optimised for read operations but no real support for transactional updates. Maybe not the most ideal storage mechanism but unfortunately one that is used by a lot of companies to store user profile data (demanded by most of our customers).

I guess my hope was that it would be possible to get Hibernate to provide some assistance with marshalling attributes to and from an LDAP store and avoiding our team having to learn another mapping tool just for LDAP support. Ideally just the mapping file would have to be switched and voila LDAP connectivity would be supported.

In our case user profile data does not usually require demanding entity relationships, in fact generally we find it is a set of one-to-one related tables/groups collecting different business domain user profile attributes with the occasional one-to-many relationship. Perfectly representable in both an RDBMS and an LDAP store.

I realise that Hibernate has been designed specifically for relational databases using an SQL protocol but in some ways LDAP can be regarded as a very limited RDBMS and therefore close enough for Hibernate to be used.

Anyway I'm going to have a look at the JDBC/LDAP bridge by OctetString to see if that can assist with LDAP integration. Hopefully it will be straight forward but I'm sure that is being overly optimistic ;)