LDAP storage for contacts : Any quick recommendations

==== Required information ====
- iRedMail version: 0.9
- Store mail accounts in which backend (LDAP/MySQL/PGSQL): MySQL
- Web server (Apache or Nginx): Nginx
- Linux/BSD distribution name and version:
- Related log if you're reporting an issue:
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Hi Zhang,
I really want to say thank you for creating iRedmail. It has helped me leave Gmail though I am still having small hiccups(but nonetheless its been helpful). i am right now trying to figure out a way to manage all email contacts. I know LDAP is useful for this. Do you know any quick way to load all gmail contacts onto the LDAP server?
Please advise.
Thanks
Kevin