LDAP lookups from Emacs

| categories: emacs, helm | tags:

Now that I have email and Cisco Jabber totally integrated into Emacs it would be nice to tap into the CMU LDAP (Lightweight Directory Access Protocol) service to find emails and phone numbers. We to use the ldapsearch command-line utility to query our LDAP service like this to find an email address.

You might like the video explanation here: https://www.youtube.com/watch?v=N7AaKHRd9uw

(shell-command-to-string "ldapsearch -x -LLL -h ldap.andrew.cmu.edu -b ou=Person,dc=cmu,dc=edu cn=\"John Kitchin\"")
dn: guid=1976CCAA-B465-11D8-8000-080020CC75D3,ou=person,dc=cmu,dc=edu
objectClass: cmuPerson
eduPersonPrimaryAffiliation: Faculty
guid: 1976CCAA-B465-11D8-8000-080020CC75D3
cmuPrivate: homePostalAddress
cmuPrivate: homePhone
cn: John Kitchin
givenName: John
sn: Kitchin
cmuPrimaryCampus: Pittsburgh
cmuCampus: Pittsburgh
cmuAndrewId: jkitchin
cmueduId: jkitchin
cmuAndrewCommonNamespaceId: jkitchin
mail: jkitchin@cmu.edu
eduPersonSchoolCollegeName: CIT - Consolidated
cmuPersonPrincipalName: jkitchin@ANDREW.CMU.EDU
postalAddress: DH A207F
cmuDepartment: Chemical Engineering
cmuDepartment: MSE: Materials Science & Engineering
cmuPersonAffiliation: Tenure-Track Faculty
eduPersonAffiliation: Faculty
cmuAccount: uid=jkitchin,ou=account,dc=andrew,dc=cmu,dc=edu
cmuAccount: uid=jkitchin,ou=account,dc=cmu,dc=edu
cmuActiveDN: uid=jkitchin,ou=account,dc=andrew,dc=cmu,dc=edu
cmuActiveDN: uid=jkitchin,ou=account,dc=cmu,dc=edu
title: Professor
telephoneNumber: +1 412 268 7803

We actually get LDIF data from ldapsearch with a lot of details. Next we wrap the output in a function that converts each result from ldapsearch into a p-list that we will use later in a helm function to help us select a match.

(defun ldap-query (query-string)
  "Send QUERY-STRING to our ldap server and parse results into a
list of p-lists for each entry returned."
  (interactive "sLDAP query: ")
  (let ((output (butlast (split-string
                           (format (concat  "ldapsearch -x -LLL "
                                            "-h ldap.andrew.cmu.edu "
                                            "-b ou=Person,dc=cmu,dc=edu %s")
        (lines '())
        (result '())
        (results '(())))
    ;; cleanup trailing lines and ignore initial lines
    (loop for line in output
           ;; join lines that run over
           ((s-starts-with? " " line)
            (setf (car (last lines))
                  (concat (car (last lines)) line)))
           ;; ignore this
           ((string-match "Size limit exceeded" line)
            (add-to-list 'lines line t))))

    ;; now we need to parse the lines. A new entry starts with a dn: line.
    (dolist (line lines)
       ((s-starts-with? "dn:" line)
        ;; add new entry
        (add-to-list 'results `(:dn ,line)))
       ((string-match ":" line)
        (let* ((s (split-string line ":"))
               (prop (intern (concat ":" (s-trim (car s)))))
               (val (s-trim (cadr s))))
          (setf (car results) (plist-put (car results) prop val))))))
    ;; last result seems to be nil so we drop it
    (-filter (lambda (x) (not (null x))) results)))

Here is an example of that function:

(ldap-query "cn=\"John Kitchin\"")
((:dn "dn: guid=1976CCAA-B465-11D8-8000-080020CC75D3,ou=person,dc=cmu,dc=edu" :objectClass "cmuPerson" :eduPersonPrimaryAffiliation "Faculty" :guid "1976CCAA-B465-11D8-8000-080020CC75D3" :cmuPrivate "homePhone" :cn "John Kitchin" :givenName "John" :sn "Kitchin" :cmuPrimaryCampus "Pittsburgh" :cmuCampus "Pittsburgh" :cmuAndrewId "jkitchin" :cmueduId "jkitchin" :cmuAndrewCommonNamespaceId "jkitchin" :mail "jkitchin@cmu.edu" :eduPersonSchoolCollegeName "CIT - Consolidated" :cmuPersonPrincipalName "jkitchin@ANDREW.CMU.EDU" :postalAddress "DH A207F" :cmuDepartment "MSE" :cmuPersonAffiliation "Tenure-Track Faculty" :eduPersonAffiliation "Faculty" :cmuAccount "uid=jkitchin,ou=account,dc=cmu,dc=edu" :cmuActiveDN "uid=jkitchin,ou=account,dc=cmu,dc=edu" :title "Professor" :telephoneNumber "+1 412 268 7803"))

Now, we wrap a helm function around that to give us a nice menu to select entries from, and a few actions like sending an email, calling, copying the name and email, and seeing the information in a reasonable way. We also add a fallback method in case we don't find what we want and need to do a new search.

(defun helm-ldap (query-string)
  (interactive "sLDAP query: ")
   `(((name . "HELM ldap")
      (candidates . ,(mapcar
                      (lambda (x)
                           (or (plist-get x :title) " "))
                          (plist-get x :cn)
                          (plist-get x :mail)
                          (plist-get x :cmuDisplayAddress)
                          (or (plist-get x :telephoneNumber) " "))
                       (if (string-match "=" query-string)
                         (concat "cn=*" query-string "*")))))
      (action . (("Email" . (lambda (x)
                              (insert (plist-get x :mail))
                 ("Call" . (lambda (x)
                              (plist-get x :telephoneNumber))))
                 ("Copy Name and email address" . (lambda (x)
                                                      "%s <%s>"
                                                      (plist-get x :cn)
                                                      (plist-get x :mail)))))
                 ("Information" . (lambda (x)
                                     (get-buffer-create "*helm ldap*"))
                                    (dolist (key (cl-loop
                                                  for key in x by #'cddr
                                                  collect key))
                                      (insert (format "|%s | %s|\n"
                                                      key (plist-get x key))))
                                    (goto-char 0)
                                    (insert "press q to quit.\n\n")
                                    (setq buffer-read-only t)
                                    (use-local-map (copy-keymap org-mode-map))
                                    (local-set-key "q"
                                                   #'(lambda ()
                                                       (quit-window t))))))))
     ;; fallback action
     ((name . "New search")
      (action . (lambda (x) (helm-ldap x)))))))

That is pretty convenient!

John Kitchin <jkitchin@cmu.edu>

Copyright (C) 2015 by John Kitchin. See the License for information about copying.

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Org-mode version = 8.2.10

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