LDAP support is added by means of ldap.el, which is part of
Emacs. ldap.el needs an external program called
ldapsearch, available as part of OpenLDAP
(https://www.openldap.org/). The configurations in this section
were tested with OpenLDAP 2.4.23.
Most servers use LDAP-over-SSL these days; the examples here reflect that. The other possibilities are:
Include auth simple in ldap-host-parameters-alist, which
causes the -x option to be passed to ldapsearch.
Pass any required extra options to ldapsearch using
ldap-ldapsearch-args.
The following examples use a base of
ou=people,dc=gnu,dc=org and the host name
ldap.gnu.org, a server that supports LDAP-over-SSL (the
ldaps protocol, with default port 636) and which
requires authentication by the user emacsuser with password
s3cr3t.
These configurations are meant to be self-contained; that is, each provides everything required for sensible TAB-completion of email fields. BBDB lookups are attempted first; if a matching BBDB entry is found then EUDC will not attempt any LDAP lookups.
Wildcard LDAP lookups are supported using the * character. For
example, attempting to TAB-complete the following:
To: * Smith
will return all LDAP entries with surnames that begin with
Smith. In every LDAP query it makes, EUDC implicitly appends
the wildcard character to the end of the last word, except if the word
corresponds to an attribute which is a member of
eudc-ldap-no-wildcard-attributes.