lisp/org-gnus.el

   1 ;;; org-gnus.el --- Support for links to Gnus groups and messages from within Org-mode
   2
   3 ;; Copyright (C) 2004-2012 Free Software Foundation, Inc.
   4
   5 ;; Author: Carsten Dominik <carsten at orgmode dot org>
   6 ;;         Tassilo Horn <tassilo at member dot fsf dot org>
   7 ;; Keywords: outlines, hypermedia, calendar, wp
   8 ;; Homepage: http://orgmode.org
   9 ;;
  10 ;; This file is part of GNU Emacs.
  11 ;;
  12 ;; GNU Emacs is free software: you can redistribute it and/or modify
  13 ;; it under the terms of the GNU General Public License as published by
  14 ;; the Free Software Foundation, either version 3 of the License, or
  15 ;; (at your option) any later version.
  16
  17 ;; GNU Emacs is distributed in the hope that it will be useful,
  18 ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
  19 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  20 ;; GNU General Public License for more details.
  21
  22 ;; You should have received a copy of the GNU General Public License
  23 ;; along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.
  24 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
  25 ;;
  26 ;;; Commentary:
  27
  28 ;; This file implements links to Gnus groups and messages from within Org-mode.
  29 ;; Org-mode loads this module by default - if this is not what you want,
  30 ;; configure the variable `org-modules'.
  31
  32 ;;; Code:
  33
  34 (require 'org)
  35 (require 'gnus-util)
  36 (eval-when-compile (require 'gnus-sum))
  37
  38 ;; Declare external functions and variables
  39 (declare-function message-fetch-field "message" (header &optional not-all))
  40 (declare-function message-narrow-to-head-1 "message" nil)
  41 (declare-function nnimap-group-overview-filename "nnimap" (group server))
  42 ;; The following line suppresses a compiler warning stemming from gnus-sum.el
  43 (declare-function gnus-summary-last-subject "gnus-sum" nil)
  44 ;; Customization variables
  45
  46 (when (fboundp 'defvaralias)
  47   (defvaralias 'org-usenet-links-prefer-google 'org-gnus-prefer-web-links))
  48
  49 (defcustom org-gnus-prefer-web-links nil
  50   "If non-nil, `org-store-link' creates web links to Google groups or Gmane.
  51 When nil, Gnus will be used for such links.
  52 Using a prefix arg to the command \\[org-store-link] (`org-store-link')
  53 negates this setting for the duration of the command."
  54   :group 'org-link-store
  55   :type 'boolean)
  56
  57 (defcustom org-gnus-nnimap-query-article-no-from-file nil
  58   "If non-nil, `org-gnus-follow-link' will try to translate
  59 Message-Ids to article numbers by querying the .overview file.
  60 Normally, this translation is done by querying the IMAP server,
  61 which is usually very fast.  Unfortunately, some (maybe badly
  62 configured) IMAP servers don't support this operation quickly.
  63 So if following a link to a Gnus article takes ages, try setting
  64 this variable to `t'."
  65   :group 'org-link-store
  66   :version "24.1"
  67   :type 'boolean)
  68
  69
  70 ;; Install the link type
  71 (org-add-link-type "gnus" 'org-gnus-open)
  72 (add-hook 'org-store-link-functions 'org-gnus-store-link)
  73
  74 ;; Implementation
  75
  76 (defun org-gnus-nnimap-cached-article-number (group server message-id)
  77   "Return cached article number (uid) of message in GROUP on SERVER.
  78 MESSAGE-ID is the message-id header field that identifies the
  79 message.  If the uid is not cached, return nil."
  80   (with-temp-buffer
  81     (let ((nov (nnimap-group-overview-filename group server)))
  82       (when (file-exists-p nov)
  83         (mm-insert-file-contents nov)
  84         (set-buffer-modified-p nil)
  85         (goto-char (point-min))
  86         (catch 'found
  87           (while (search-forward message-id nil t)
  88             (let ((hdr (split-string (thing-at-point 'line) "\t")))
  89               (if (string= (nth 4 hdr) message-id)
  90                   (throw 'found (nth 0 hdr))))))))))
  91
  92 (defun org-gnus-group-link (group)
  93   "Create a link to the Gnus group GROUP.
  94 If GROUP is a newsgroup and `org-gnus-prefer-web-links' is
  95 non-nil, create a link to groups.google.com or gmane.org.
  96 Otherwise create a link to the group inside Gnus.
  97
  98 If `org-store-link' was called with a prefix arg the meaning of
  99 `org-gnus-prefer-web-links' is reversed."
 100   (let ((unprefixed-group (replace-regexp-in-string "^[^:]+:" "" group)))
 101     (if (and (string-match "^nntp" group) ;; Only for nntp groups
 102              (org-xor current-prefix-arg
 103                       org-gnus-prefer-web-links))
 104         (concat (if (string-match "gmane" unprefixed-group)
 105                     "http://news.gmane.org/"
 106                   "http://groups.google.com/group/")
 107                 unprefixed-group)
 108       (concat "gnus:" group))))
 109
 110 (defun org-gnus-article-link (group newsgroups message-id x-no-archive)
 111   "Create a link to a Gnus article.
 112 The article is specified by its MESSAGE-ID.  Additional
 113 parameters are the Gnus GROUP, the NEWSGROUPS the article was
 114 posted to and the X-NO-ARCHIVE header value of that article.
 115
 116 If GROUP is a newsgroup and `org-gnus-prefer-web-links' is
 117 non-nil, create a link to groups.google.com or gmane.org.
 118 Otherwise create a link to the article inside Gnus.
 119
 120 If `org-store-link' was called with a prefix arg the meaning of
 121 `org-gnus-prefer-web-links' is reversed."
 122   (if (and (org-xor current-prefix-arg org-gnus-prefer-web-links)
 123            newsgroups     ;; Make web links only for nntp groups
 124            (not x-no-archive)) ;; and if X-No-Archive isn't set.
 125       (format (if (string-match "gmane\\." newsgroups)
 126                   "http://mid.gmane.org/%s"
 127                 "http://groups.google.com/groups/search?as_umsgid=%s")
 128               (org-fixup-message-id-for-http message-id))
 129     (concat "gnus:" group "#" message-id)))
 130
 131 (defun org-gnus-store-link ()
 132   "Store a link to a Gnus folder or message."
 133   (cond
 134    ((eq major-mode 'gnus-group-mode)
 135     (let* ((group (cond ((fboundp 'gnus-group-group-name) ; depending on Gnus
 136                          (gnus-group-group-name))         ; version
 137                         ((fboundp 'gnus-group-name)
 138                          (gnus-group-name))
 139                         (t "???")))
 140            desc link)
 141       (when group
 142         (org-store-link-props :type "gnus" :group group)
 143         (setq desc (org-gnus-group-link group)
 144               link desc)
 145         (org-add-link-props :link link :description desc)
 146         link)))
 147
 148    ((memq major-mode '(gnus-summary-mode gnus-article-mode))
 149     (let* ((group gnus-newsgroup-name)
 150            (header (with-current-buffer gnus-summary-buffer
 151                      (gnus-summary-article-header)))
 152            (from (mail-header-from header))
 153            (message-id (org-remove-angle-brackets (mail-header-id header)))
 154            (date (org-trim (mail-header-date header)))
 155            (date-ts (and date
 156                          (ignore-errors
 157                            (format-time-string
 158                             (org-time-stamp-format t)
 159                             (date-to-time date)))))
 160            (date-ts-ia (and date
 161                             (ignore-errors
 162                               (format-time-string
 163                                (org-time-stamp-format t t)
 164                                (date-to-time date)))))
 165            (subject (copy-sequence (mail-header-subject header)))
 166            (to (cdr (assq 'To (mail-header-extra header))))
 167            newsgroups x-no-archive desc link)
 168       ;; Remove text properties of subject string to avoid Emacs bug
 169       ;; #3506
 170       (set-text-properties 0 (length subject) nil subject)
 171
 172       ;; Fetching an article is an expensive operation; newsgroup and
 173       ;; x-no-archive are only needed for web links.
 174       (when (org-xor current-prefix-arg org-gnus-prefer-web-links)
 175         ;; Make sure the original article buffer is up-to-date
 176         (save-window-excursion (gnus-summary-select-article))
 177         (setq to (or to (gnus-fetch-original-field "To"))
 178               newsgroups (gnus-fetch-original-field "Newsgroups")
 179               x-no-archive (gnus-fetch-original-field "x-no-archive")))
 180       (org-store-link-props :type "gnus" :from from :subject subject
 181                             :message-id message-id :group group :to to)
 182       (when date
 183         (org-add-link-props :date date :date-timestamp date-ts
 184                             :date-timestamp-inactive date-ts-ia))
 185       (setq desc (org-email-link-description)
 186             link (org-gnus-article-link
 187                   group newsgroups message-id x-no-archive))
 188       (org-add-link-props :link link :description desc)
 189       link))
 190    ((eq major-mode 'message-mode)
 191     (setq org-store-link-plist nil)  ; reset
 192     (save-excursion
 193       (save-restriction
 194         (message-narrow-to-headers)
 195         (and (not (message-fetch-field "Message-ID"))
 196              (message-generate-headers '(Message-ID)))
 197         (goto-char (point-min))
 198         (re-search-forward "^Message-ID: *.*$" nil t)
 199         (put-text-property (match-beginning 0) (match-end 0) 'message-deletable nil)
 200         (let ((gcc (car (last
 201                          (message-unquote-tokens
 202                           (message-tokenize-header (mail-fetch-field "gcc" nil t) " ,")))))
 203               (id (org-remove-angle-brackets (mail-fetch-field "Message-ID")))
 204               (to (mail-fetch-field "To"))
 205               (from (mail-fetch-field "From"))
 206               (subject (mail-fetch-field "Subject"))
 207               desc link
 208               newsgroup xarchive)       ; those are always nil for gcc
 209           (and (not gcc)
 210                (error "Can not create link: No Gcc header found"))
 211           (org-store-link-props :type "gnus" :from from :subject subject
 212                                 :message-id id :group gcc :to to)
 213           (setq desc (org-email-link-description)
 214                 link (org-gnus-article-link
 215                       gcc newsgroup id xarchive))
 216           (org-add-link-props :link link :description desc)
 217           link))))))
 218
 219 (defun org-gnus-open-nntp (path)
 220   "Follow the nntp: link specified by PATH."
 221   (let* ((spec (split-string path "/"))
 222          (server (split-string (nth 2 spec) "@"))
 223          (group (nth 3 spec))
 224          (article (nth 4 spec)))
 225     (org-gnus-follow-link
 226      (format "nntp+%s:%s" (or (cdr server) (car server)) group)
 227      article)))
 228
 229 (defun org-gnus-open (path)
 230   "Follow the Gnus message or folder link specified by PATH."
 231   (let (group article)
 232     (if (not (string-match "\\`\\([^#]+\\)\\(#\\(.*\\)\\)?" path))
 233         (error "Error in Gnus link"))
 234     (setq group (match-string 1 path)
 235           article (match-string 3 path))
 236     (when group
 237       (setq group (org-no-properties group)))
 238     (when article
 239       (setq article (org-no-properties article)))
 240     (org-gnus-follow-link group article)))
 241
 242 (defun org-gnus-follow-link (&optional group article)
 243   "Follow a Gnus link to GROUP and ARTICLE."
 244   (require 'gnus)
 245   (funcall (cdr (assq 'gnus org-link-frame-setup)))
 246   (if gnus-other-frame-object (select-frame gnus-other-frame-object))
 247   (when group
 248     (setq group (org-no-properties group)))
 249   (when article
 250     (setq article (org-no-properties article)))
 251   (cond ((and group article)
 252          (gnus-activate-group group)
 253          (condition-case nil
 254              (let* ((method (gnus-find-method-for-group group))
 255                     (backend (car method))
 256                     (server (cadr method)))
 257                (cond
 258                 ((eq backend 'nndoc)
 259                  (if (gnus-group-read-group t nil group)
 260                      (gnus-summary-goto-article article nil t)
 261                    (message "Couldn't follow gnus link.  %s"
 262                             "The summary couldn't be opened.")))
 263                 (t
 264                  (let ((articles 1)
 265                        group-opened)
 266                    (when (and (eq backend 'nnimap)
 267                               org-gnus-nnimap-query-article-no-from-file)
 268                      (setq article
 269                            (or (org-gnus-nnimap-cached-article-number
 270                                 (nth 1 (split-string group ":"))
 271                                 server (concat "<" article ">")) article)))
 272                    (while (and (not group-opened)
 273                                ;; stop on integer overflows
 274                                (> articles 0))
 275                      (setq group-opened (gnus-group-read-group
 276                                          articles t group)
 277                            articles (if (< articles 16)
 278                                         (1+ articles)
 279                                       (* articles 2))))
 280                    (if group-opened
 281                        (gnus-summary-goto-article article nil t)
 282                      (message "Couldn't follow gnus link.  %s"
 283                               "The summary couldn't be opened."))))))
 284            (quit (message "Couldn't follow gnus link.  %s"
 285                           "The linked group is empty."))))
 286         (group (gnus-group-jump-to-group group))))
 287
 288 (defun org-gnus-no-new-news ()
 289   "Like `M-x gnus' but doesn't check for new news."
 290   (if (not (gnus-alive-p)) (gnus)))
 291
 292 (provide 'org-gnus)
 293
 294
 295 ;;; org-gnus.el ends here