lisp/org-gnus.el

   1 ;;; org-gnus.el --- Support for Links to Gnus Groups and Messages -*- lexical-binding: t; -*-
   2
   3 ;; Copyright (C) 2004-2017 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 <https://www.gnu.org/licenses/>.
  24 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
  25 ;;
  26 ;;; Commentary:
  27
  28 ;; This file implements links to Gnus groups and messages from within Org.
  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 'gnus-sum)
  35 (require 'gnus-util)
  36 (require 'nnheader)
  37 (require 'nnir)
  38 (require 'org)
  39
  40 \f
  41 ;;; Declare external functions and variables
  42
  43 (declare-function gnus-activate-group "gnus-start" (group &optional scan dont-check method dont-sub-check))
  44 (declare-function gnus-find-method-for-group "gnus" (group &optional info))
  45 (declare-function gnus-group-group-name "gnus-group")
  46 (declare-function gnus-group-jump-to-group "gnus-group" (group &optional prompt))
  47 (declare-function gnus-group-read-group "gnus-group" (&optional all no-article group select-articles))
  48 (declare-function message-fetch-field "message" (header &optional not-all))
  49 (declare-function message-generate-headers "message" (headers))
  50 (declare-function message-narrow-to-headers "message")
  51 (declare-function message-tokenize-header "message" (header &optional separator))
  52 (declare-function message-unquote-tokens "message" (elems))
  53 (declare-function nnvirtual-map-article "nnvirtual" (article))
  54
  55 (defvar gnus-newsgroup-name)
  56 (defvar gnus-summary-buffer)
  57 (defvar gnus-other-frame-object)
  58
  59 \f
  60 ;;; Customization variables
  61
  62 (defcustom org-gnus-prefer-web-links nil
  63   "If non-nil, `org-store-link' creates web links to Google groups or Gmane.
  64 \\<org-mode-map>When nil, Gnus will be used for such links.
  65 Using a prefix argument to the command `\\[org-store-link]' (`org-store-link')
  66 negates this setting for the duration of the command."
  67   :group 'org-link-store
  68   :type 'boolean)
  69
  70 (defcustom org-gnus-no-server nil
  71   "Should Gnus be started using `gnus-no-server'?"
  72   :group 'org-gnus
  73   :version "24.4"
  74   :package-version '(Org . "8.0")
  75   :type 'boolean)
  76
  77 \f
  78 ;;; Install the link type
  79
  80 (org-link-set-parameters "gnus"
  81                          :follow #'org-gnus-open
  82                          :store #'org-gnus-store-link)
  83 \f
  84 ;;; Implementation
  85
  86 (defun org-gnus-group-link (group)
  87   "Create a link to the Gnus group GROUP.
  88 If GROUP is a newsgroup and `org-gnus-prefer-web-links' is
  89 non-nil, create a link to groups.google.com or gmane.org.
  90 Otherwise create a link to the group inside Gnus.
  91
  92 If `org-store-link' was called with a prefix arg the meaning of
  93 `org-gnus-prefer-web-links' is reversed."
  94   (let ((unprefixed-group (replace-regexp-in-string "^[^:]+:" "" group)))
  95     (if (and (string-prefix-p "nntp" group) ;; Only for nntp groups
  96              (org-xor current-prefix-arg
  97                       org-gnus-prefer-web-links))
  98         (concat (if (string-match "gmane" unprefixed-group)
  99                     "http://news.gmane.org/"
 100                   "http://groups.google.com/group/")
 101                 unprefixed-group)
 102       (concat "gnus:" group))))
 103
 104 (defun org-gnus-article-link (group newsgroups message-id x-no-archive)
 105   "Create a link to a Gnus article.
 106 The article is specified by its MESSAGE-ID.  Additional
 107 parameters are the Gnus GROUP, the NEWSGROUPS the article was
 108 posted to and the X-NO-ARCHIVE header value of that article.
 109
 110 If GROUP is a newsgroup and `org-gnus-prefer-web-links' is
 111 non-nil, create a link to groups.google.com or gmane.org.
 112 Otherwise create a link to the article inside Gnus.
 113
 114 If `org-store-link' was called with a prefix arg the meaning of
 115 `org-gnus-prefer-web-links' is reversed."
 116   (if (and (org-xor current-prefix-arg org-gnus-prefer-web-links)
 117            newsgroups     ;; Make web links only for nntp groups
 118            (not x-no-archive)) ;; and if X-No-Archive isn't set.
 119       (format (if (string-match "gmane\\." newsgroups)
 120                   "http://mid.gmane.org/%s"
 121                 "http://groups.google.com/groups/search?as_umsgid=%s")
 122               (org-fixup-message-id-for-http message-id))
 123     (concat "gnus:" group "#" message-id)))
 124
 125 (defun org-gnus-store-link ()
 126   "Store a link to a Gnus folder or message."
 127   (pcase major-mode
 128     (`gnus-group-mode
 129      (let ((group (gnus-group-group-name)))
 130        (when group
 131          (org-store-link-props :type "gnus" :group group)
 132          (let ((description (org-gnus-group-link group)))
 133            (org-add-link-props :link description :description description)
 134            description))))
 135     ((or `gnus-summary-mode `gnus-article-mode)
 136      (let* ((group
 137              (pcase (gnus-find-method-for-group gnus-newsgroup-name)
 138                (`(nnvirtual . ,_)
 139                 (save-excursion
 140                   (car (nnvirtual-map-article (gnus-summary-article-number)))))
 141                (`(nnir . ,_)
 142                 (save-excursion
 143                   (nnir-article-group (gnus-summary-article-number))))
 144                (_ gnus-newsgroup-name)))
 145             (header (with-current-buffer gnus-summary-buffer
 146                       (gnus-summary-article-header)))
 147             (from (mail-header-from header))
 148             (message-id (org-unbracket-string "<" ">" (mail-header-id header)))
 149             (date (org-trim (mail-header-date header)))
 150             ;; Remove text properties of subject string to avoid Emacs
 151             ;; bug #3506.
 152             (subject (org-no-properties
 153                       (copy-sequence (mail-header-subject header))))
 154             (to (cdr (assq 'To (mail-header-extra header))))
 155             newsgroups x-no-archive)
 156        ;; Fetching an article is an expensive operation; newsgroup and
 157        ;; x-no-archive are only needed for web links.
 158        (when (org-xor current-prefix-arg org-gnus-prefer-web-links)
 159          ;; Make sure the original article buffer is up-to-date.
 160          (save-window-excursion (gnus-summary-select-article))
 161          (setq to (or to (gnus-fetch-original-field "To")))
 162          (setq newsgroups (gnus-fetch-original-field "Newsgroups"))
 163          (setq x-no-archive (gnus-fetch-original-field "x-no-archive")))
 164        (org-store-link-props :type "gnus" :from from :date date :subject subject
 165                              :message-id message-id :group group :to to)
 166        (let ((link (org-gnus-article-link
 167                     group newsgroups message-id x-no-archive))
 168              (description (org-email-link-description)))
 169          (org-add-link-props :link link :description description)
 170          link)))
 171     (`message-mode
 172      (setq org-store-link-plist nil)    ;reset
 173      (save-excursion
 174        (save-restriction
 175          (message-narrow-to-headers)
 176          (unless (message-fetch-field "Message-ID")
 177            (message-generate-headers '(Message-ID)))
 178          (goto-char (point-min))
 179          (re-search-forward "^Message-ID:" nil t)
 180          (put-text-property (line-beginning-position) (line-end-position)
 181                             'message-deletable nil)
 182          (let ((gcc (org-last (message-unquote-tokens
 183                                (message-tokenize-header
 184                                 (mail-fetch-field "gcc" nil t) " ,"))))
 185                (id (org-unbracket-string "<" ">"
 186                                          (mail-fetch-field "Message-ID")))
 187                (to (mail-fetch-field "To"))
 188                (from (mail-fetch-field "From"))
 189                (subject (mail-fetch-field "Subject"))
 190                newsgroup xarchive)      ;those are always nil for gcc
 191            (unless gcc (error "Can not create link: No Gcc header found"))
 192            (org-store-link-props :type "gnus" :from from :subject subject
 193                                  :message-id id :group gcc :to to)
 194            (let ((link (org-gnus-article-link gcc newsgroup id xarchive))
 195                  (description (org-email-link-description)))
 196              (org-add-link-props :link link :description description)
 197              link)))))))
 198
 199 (defun org-gnus-open-nntp (path)
 200   "Follow the nntp: link specified by PATH."
 201   (let* ((spec (split-string path "/"))
 202          (server (split-string (nth 2 spec) "@"))
 203          (group (nth 3 spec))
 204          (article (nth 4 spec)))
 205     (org-gnus-follow-link
 206      (format "nntp+%s:%s" (or (cdr server) (car server)) group)
 207      article)))
 208
 209 (defun org-gnus-open (path)
 210   "Follow the Gnus message or folder link specified by PATH."
 211   (unless (string-match "\\`\\([^#]+\\)\\(#\\(.*\\)\\)?" path)
 212     (error "Error in Gnus link %S" path))
 213   (let ((group (match-string-no-properties 1 path))
 214         (article (match-string-no-properties 3 path)))
 215     (org-gnus-follow-link group article)))
 216
 217 (defun org-gnus-follow-link (&optional group article)
 218   "Follow a Gnus link to GROUP and ARTICLE."
 219   (require 'gnus)
 220   (funcall (cdr (assq 'gnus org-link-frame-setup)))
 221   (when gnus-other-frame-object (select-frame gnus-other-frame-object))
 222   (let ((group (org-no-properties group))
 223         (article (org-no-properties article)))
 224     (cond
 225      ((and group article)
 226       (gnus-activate-group group)
 227       (condition-case nil
 228           (let ((msg "Couldn't follow Gnus link.  Summary couldn't be opened."))
 229             (pcase (gnus-find-method-for-group group)
 230               (`(nndoc . ,_)
 231                (if (gnus-group-read-group t nil group)
 232                    (gnus-summary-goto-article article nil t)
 233                  (message msg)))
 234               (_
 235                (let ((articles 1)
 236                      group-opened)
 237                  (while (and (not group-opened)
 238                              ;; Stop on integer overflows.
 239                              (> articles 0))
 240                    (setq group-opened (gnus-group-read-group articles t group))
 241                    (setq articles (if (< articles 16)
 242                                       (1+ articles)
 243                                     (* articles 2))))
 244                  (if group-opened
 245                      (gnus-summary-goto-article article nil t)
 246                    (message msg))))))
 247         (quit
 248          (message "Couldn't follow Gnus link.  The linked group is empty."))))
 249      (group (gnus-group-jump-to-group group)))))
 250
 251 (defun org-gnus-no-new-news ()
 252   "Like `\\[gnus]' but doesn't check for new news."
 253   (cond ((gnus-alive-p) nil)
 254         (org-gnus-no-server (gnus-no-server))
 255         (t (gnus))))
 256
 257 (provide 'org-gnus)
 258
 259
 260 ;;; org-gnus.el ends here