Hello,
Just in case, I share another opensource project that offer REST API for this type of modification :
LdapSaisie https://ldapsaisie.org
The REST API is a quite new feature (one or two years, I don't remember) but this project was started in 2007. I'm the main developer of this application and I maintain it as part of my job at Easter-eggs (and in my spare time).
For more information about the project and it's API feature, you could take a look at the documentation (in french, sorry) :
https://ldapsaisie.org/doc/all-in-one/LdapSaisie.html#api
Freely,