lisp/gnus/nndb.el

   1 ;;; nndb.el --- nndb access for Gnus
   2
   3 ;; Copyright (C) 1997, 1998, 2000, 2003, 2004, 2005
   4 ;;        Free Software Foundation, Inc.
   5
   6 ;; Author: Masanobu UMEDA <umerin@flab.flab.fujitsu.junet>
   7 ;;         Kai Grossjohann <grossjohann@ls6.informatik.uni-dortmund.de>
   8 ;;         Joe Hildebrand <joe.hildebrand@ilg.com>
   9 ;;         David Blacka <davidb@rwhois.net>
  10 ;; Keywords: news
  11
  12 ;; This file is part of GNU Emacs.
  13
  14 ;; GNU Emacs is free software; you can redistribute it and/or modify
  15 ;; it under the terms of the GNU General Public License as published by
  16 ;; the Free Software Foundation; either version 2, or (at your option)
  17 ;; any later version.
  18
  19 ;; GNU Emacs is distributed in the hope that it will be useful,
  20 ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
  21 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  22 ;; GNU General Public License for more details.
  23
  24 ;; You should have received a copy of the GNU General Public License
  25 ;; along with GNU Emacs; see the file COPYING.  If not, write to the
  26 ;; Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  27 ;; Boston, MA 02111-1307, USA.
  28
  29 ;;; Commentary:
  30
  31 ;;; This was based upon Kai Grossjohan's shamessly snarfed code and
  32 ;;; further modified by Joe Hildebrand.  It has been updated for Red
  33 ;;; Gnus.
  34
  35 ;; TODO:
  36 ;;
  37 ;; * Fix bug where server connection can be lost and impossible to regain
  38 ;;   This hasn't happened to me in a while; think it was fixed in Rgnus
  39 ;;
  40 ;; * make it handle different nndb servers seemlessly
  41 ;;
  42 ;; * Optimize expire if FORCE
  43 ;;
  44 ;; * Optimize move (only expire once)
  45 ;;
  46 ;; * Deal with add/deletion of groups
  47 ;;
  48 ;; * make the backend TOUCH an article when marked as expireable (will
  49 ;;   make article expire 'expiry' days after that moment).
  50
  51 ;;-
  52 ;; Register nndb with known select methods.
  53
  54 (require 'gnus-start)
  55 (unless (assoc "nndb" gnus-valid-select-methods)
  56   (gnus-declare-backend "nndb" 'mail 'respool 'address 'prompt-address))
  57
  58 ;;; Code:
  59
  60 (require 'nnmail)
  61 (require 'nnheader)
  62 (require 'nntp)
  63 (eval-when-compile (require 'cl))
  64
  65 ;; Declare nndb as derived from nntp
  66
  67 (nnoo-declare nndb nntp)
  68
  69 ;; Variables specific to nndb
  70
  71 ;;- currently not used but just in case...
  72 (defvoo nndb-deliver-program "nndel"
  73   "*The program used to put a message in an NNDB group.")
  74
  75 (defvoo nndb-server-side-expiry nil
  76   "If t, expiry calculation will occur on the server side.")
  77
  78 (defvoo nndb-set-expire-date-on-mark nil
  79   "If t, the expiry date for a given article will be set to the time
  80 it was marked as expireable; otherwise the date will be the time the
  81 article was posted to nndb")
  82
  83 ;; Variables copied from nntp
  84
  85 (defvoo nndb-server-opened-hook '(nntp-send-authinfo-from-file)
  86   "Like nntp-server-opened-hook."
  87   nntp-server-opened-hook)
  88
  89 (defvoo nndb-address "localhost"
  90   "*The name of the NNDB server."
  91   nntp-address)
  92
  93 (defvoo nndb-port-number 9000
  94   "*Port number to connect to."
  95   nntp-port-number)
  96
  97 ;; change to 'news if you are actually using nndb for news
  98 (defvoo nndb-article-type 'mail)
  99
 100 (defvoo nndb-status-string nil "" nntp-status-string)
 101
 102 \f
 103
 104 (defconst nndb-version "nndb 0.7"
 105   "Version numbers of this version of NNDB.")
 106
 107 \f
 108 ;;; Interface functions.
 109
 110 (nnoo-define-basics nndb)
 111
 112 ;;------------------------------------------------------------------
 113
 114 ;; this function turns the lisp list into a string list.  There is
 115 ;; probably a more efficient way to do this.
 116 (defun nndb-build-article-string (articles)
 117   (let (art-string art)
 118     (while articles
 119       (setq art (pop articles))
 120       (setq art-string (concat art-string art " ")))
 121     art-string))
 122
 123 (defun nndb-build-expire-rest-list (total expire)
 124   (let (art rest)
 125     (while total
 126       (setq art (pop total))
 127       (if (memq art expire)
 128           ()
 129         (push art rest)))
 130     rest))
 131
 132
 133 ;;
 134 (deffoo nndb-request-type (group &optional article)
 135   nndb-article-type)
 136
 137 ;; nndb-request-update-info does not exist and is not needed
 138
 139 ;; nndb-request-update-mark does not exist; it should be used to TOUCH
 140 ;; articles as they are marked exipirable
 141 (defun nndb-touch-article (group article)
 142   (nntp-send-command nil "X-TOUCH" article))
 143
 144 (deffoo nndb-request-update-mark
 145     (group article mark)
 146   "Sets the expiry date for ARTICLE in GROUP to now, if the mark is 'E'"
 147   (if (and nndb-set-expire-date-on-mark (string-equal mark "E"))
 148       (nndb-touch-article group article))
 149   mark)
 150
 151 ;; nndb-request-create-group -- currently this isn't necessary; nndb
 152 ;;   creates groups on demand.
 153
 154 ;; todo -- use some other time than the creation time of the article
 155 ;;         best is time since article has been marked as expirable
 156
 157 (defun nndb-request-expire-articles-local
 158   (articles &optional group server force)
 159   "Let gnus do the date check and issue the delete commands."
 160   (let (msg art delete-list (num-delete 0) rest)
 161     (nntp-possibly-change-group group server)
 162     (while articles
 163       (setq art (pop articles))
 164       (nntp-send-command "^\\([23]\\|^423\\).*\n" "X-DATE" art)
 165       (setq msg (nndb-status-message))
 166       (if (string-match "^423" msg)
 167           ()
 168         (or (string-match "'\\(.+\\)'" msg)
 169             (error "Not a valid response for X-DATE command: %s"
 170                    msg))
 171         (if (nnmail-expired-article-p
 172              group
 173              (date-to-time (substring msg (match-beginning 1) (match-end 1)))
 174              force)
 175             (progn
 176               (setq delete-list (concat delete-list " " (int-to-string art)))
 177               (setq num-delete  (1+ num-delete)))
 178           (push art rest))))
 179     (if (> (length delete-list) 0)
 180         (progn
 181           (nnheader-message 5 "Deleting %s article(s) from %s"
 182                             (int-to-string num-delete) group)
 183           (nntp-send-command "^[23].*\n" "X-DELETE" delete-list))
 184       )
 185
 186     (nnheader-message 5 "")
 187     (nconc rest articles)))
 188
 189 (defun nndb-get-remote-expire-response ()
 190   (let (list)
 191     (set-buffer nntp-server-buffer)
 192     (goto-char (point-min))
 193     (if (looking-at "^[34]")
 194        ;; x-expire returned error--presume no articles were expirable)
 195         (setq list nil)
 196       ;; otherwise, pull all of the following numbers into the list
 197       (re-search-forward "follows\r?\n?" nil t)
 198       (while (re-search-forward "^[0-9]+$" nil t)
 199       (push (string-to-number (match-string 0)) list)))
 200     list))
 201
 202 (defun nndb-request-expire-articles-remote
 203   (articles &optional group server force)
 204   "Let the nndb backend expire articles"
 205   (let (days art-string delete-list (num-delete 0))
 206     (nntp-possibly-change-group group server)
 207
 208     ;; first calculate the wait period in days
 209     (setq days (or (and nnmail-expiry-wait-function
 210                         (funcall nnmail-expiry-wait-function group))
 211     nnmail-expiry-wait))
 212     ;; now handle the special cases
 213     (cond (force
 214     (setq days 0))
 215           ((eq days 'never)
 216            ;; This isn't an expirable group.
 217           (setq days -1))
 218           ((eq days 'immediate)
 219           (setq days 0)))
 220
 221
 222     ;; build article string
 223     (setq art-string (concat days " " (nndb-build-article-string articles)))
 224     (nntp-send-command "^\.\r?\n\\|^[345].*\n" "X-EXPIRE" art-string)
 225
 226     (setq delete-list (nndb-get-remote-expire-response))
 227     (setq num-delete (length delete-list))
 228     (if (> num-delete 0)
 229         (nnheader-message 5 "Deleting %s article(s) from %s"
 230                           (int-to-string num-delete) group))
 231
 232     (nndb-build-expire-rest-list articles delete-list)))
 233
 234 (deffoo nndb-request-expire-articles
 235     (articles &optional group server force)
 236   "Expires ARTICLES from GROUP on SERVER.
 237 If FORCE, delete regardless of exiration date, otherwise use normal
 238 expiry mechanism."
 239   (if nndb-server-side-expiry
 240       (nndb-request-expire-articles-remote articles group server force)
 241     (nndb-request-expire-articles-local articles group server force)))
 242
 243 (deffoo nndb-request-move-article
 244     (article group server accept-form &optional last)
 245   "Move ARTICLE (a number) from GROUP on SERVER.
 246 Evals ACCEPT-FORM in current buffer, where the article is.
 247 Optional LAST is ignored."
 248   ;; we guess that the second arg in accept-form is the new group,
 249   ;; which it will be for nndb, which is all that matters anyway
 250   (let ((new-group (nth 1 accept-form)) result)
 251     (nntp-possibly-change-group group server)
 252
 253     ;; use the move command for nndb-to-nndb moves
 254     (if (string-match "^nndb" new-group)
 255         (let ((new-group-name (gnus-group-real-name new-group)))
 256           (nntp-send-command "^[23].*\n" "X-MOVE" article new-group-name)
 257           (cons new-group article))
 258       ;; else move normally
 259       (let ((artbuf (get-buffer-create " *nndb move*")))
 260       (and
 261        (nndb-request-article article group server artbuf)
 262        (save-excursion
 263          (set-buffer artbuf)
 264          (insert-buffer-substring nntp-server-buffer)
 265          (setq result (eval accept-form))
 266          (kill-buffer (current-buffer))
 267          result)
 268        (nndb-request-expire-articles (list article)
 269                                      group
 270                                      server
 271                                      t))
 272       result)
 273       )))
 274
 275 (deffoo nndb-request-accept-article (group server &optional last)
 276   "The article in the current buffer is put into GROUP."
 277   (nntp-possibly-change-group group server)
 278   (let (art msg)
 279     (when (nntp-send-command "^[23].*\r?\n" "ACCEPT" group)
 280       (nnheader-insert "")
 281       (nntp-send-buffer "^[23].*\n"))
 282
 283     (set-buffer nntp-server-buffer)
 284     (setq msg (buffer-string))
 285     (or (string-match "^\\([0-9]+\\)" msg)
 286         (error "nndb: %s" msg))
 287     (setq art (substring msg (match-beginning 1) (match-end 1)))
 288     (nnheader-message 5 "nndb: accepted %s" art)
 289     (list art)))
 290
 291 (deffoo nndb-request-replace-article (article group buffer)
 292   "ARTICLE is the number of the article in GROUP to be replaced with the contents of the BUFFER."
 293   (set-buffer buffer)
 294   (when (nntp-send-command "^[23].*\r?\n" "X-REPLACE" (int-to-string article))
 295     (nnheader-insert "")
 296     (nntp-send-buffer "^[23.*\n")
 297     (list (int-to-string article))))
 298
 299                             ; nndb-request-delete-group does not exist
 300                                         ; todo -- maybe later
 301
 302                             ; nndb-request-rename-group does not exist
 303                                         ; todo -- maybe later
 304
 305 ;; -- standard compatability functions
 306
 307 (deffoo nndb-status-message (&optional server)
 308   "Return server status as a string."
 309   (set-buffer nntp-server-buffer)
 310   (buffer-string))
 311
 312 ;; Import stuff from nntp
 313
 314 (nnoo-import nndb
 315   (nntp))
 316
 317 (provide 'nndb)
 318
 319 ;;; arch-tag: 83bd6fb4-58d9-4fed-a901-c6c625ad5f8a
 320 ;;; nndb.el ends here