git.shemshak.org - ~bandali/bndl.org/blob - bandali/feeds.scm

   1 ;;; Copyright © 2019 Amin Bandali <bandali@gnu.org>
   2 ;;;
   3 ;;; This program is free software; you can redistribute it and/or
   4 ;;; modify it under the terms of the GNU General Public License as
   5 ;;; published by the Free Software Foundation; either version 3 of the
   6 ;;; License, or (at your option) any later version.
   7 ;;;
   8 ;;; This program is distributed in the hope that it will be useful,
   9 ;;; but WITHOUT ANY WARRANTY; without even the implied warranty of
  10 ;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  11 ;;; General Public License for more details.
  12 ;;;
  13 ;;; You should have received a copy of the GNU General Public License
  14 ;;; along with this program. If not, see
  15 ;;; <http://www.gnu.org/licenses/>.
  16
  17 (define-module (bandali feeds)
  18   #:use-module (haunt builder atom)     ; atom-feed
  19   #:use-module (haunt builder rss)      ; rss-feed
  20   #:use-module (haunt post)             ; post-*
  21   #:use-module (ice-9 match)            ; match-lambda
  22   #:re-export (atom-feed
  23                rss-feed)
  24   #:export (atom-feeds-by-tag
  25             rss-feeds-by-tag))
  26
  27 (define* (atom-feeds-by-tag #:key
  28                             (prefix "feeds/tags")
  29                             (filter posts/reverse-chronological)
  30                             (max-entries 20)
  31                             (blog-prefix ""))
  32   "Return a builder procedure that renders an atom feed for every tag
  33 used in a post.  All arguments are optional:
  34
  35 PREFIX: The directory in which to write the feeds
  36 FILTER: The procedure called to manipulate the posts list before rendering
  37 MAX-ENTRIES: The maximum number of posts to render in each feed"
  38   (lambda (site posts)
  39     (let ((tag-groups (posts/group-by-tag posts)))
  40       (map (match-lambda
  41             ((tag . posts)
  42              ((atom-feed #:file-name (string-append prefix "/" tag ".atom")
  43                          #:subtitle (string-append "Tag: " tag)
  44                          #:filter filter
  45                          #:max-entries max-entries
  46                          #:blog-prefix blog-prefix)
  47               site posts)))
  48            tag-groups))))
  49
  50 (define* (rss-feeds-by-tag #:key
  51                            (prefix "feeds/tags")
  52                            (filter posts/reverse-chronological)
  53                            (max-entries 20)
  54                            (blog-prefix ""))
  55   "Return a builder procedure that renders an rss feed for every tag
  56 used in a post.  All arguments are optional:
  57
  58 PREFIX: The directory in which to write the feeds
  59 FILTER: The procedure called to manipulate the posts list before rendering
  60 MAX-ENTRIES: The maximum number of posts to render in each feed"
  61   (lambda (site posts)
  62     (let ((tag-groups (posts/group-by-tag posts)))
  63       (map (match-lambda
  64             ((tag . posts)
  65              ((rss-feed #:file-name (string-append prefix "/" tag ".rss")
  66                         #:subtitle (string-append "Tag: " tag)
  67                         #:filter filter
  68                         #:max-entries max-entries
  69                         #:blog-prefix blog-prefix)
  70               site posts)))
  71            tag-groups))))