ldappool - simple pooling for LDAP connections in go

The ldappool package provides simple pooling in the style of https://gopkg.in/fatih/pool.v2, in fact lots of code is taken from there and rewritten to match the ldap.Client interface in gopkg.in/ldap.v2

Notes

This is only suitable for connections which do not use Bind() after the initial connection setup, i.e. just use one user to connect to the LDAP service and do not bind again to check passwords.