nixpkgs/overlays/podl.sh

   1 #!/usr/bin/env bash
   2 # shellcheck disable=SC1004
   3 # shellcheck disable=SC2016
   4 # shellcheck disable=SC2064
   5 # shellcheck disable=SC2086
   6 # shellcheck disable=SC2155
   7 # Name: podl - podcast downloader with caching
   8 # Version: 2021-10-22
   9 # Latest version: https://git.sourcephile.fr/julm/julm-nix/tree/main/item/nixpkgs/overlays/podl.sh
  10 # Synopsis:
  11 #   $ mkdir LaMéthodeScientifique 3Blue1Brown
  12 #   $ echo >LaMéthodeScientifique/.feed http://radiofrance-podcast.net/podcast09/rss_14312.xml
  13 #   $ echo >3Blue1Brown/.feed https://youtube.com/channel/UCYO_jab_esuFRV4b17AJtAw
  14 #   $ echo >>3Blue1Brown/.feed https://www.youtube.com/feeds/videos.xml?channel_id=UCYO_jab_esuFRV4b17AJtAw
  15 #   $ podl
  16 # Description:
  17 #   podl is a wrapper around yt-dlp(1) <https://yt-dlp.org/>
  18 #   to download podcasts from feeds whose URI(s) you write
  19 #   in ".feed" files in or below the current working directory.
  20 #   The feed formats currently supported are:
  21 #   - RSS
  22 #   - Youtube's Atom
  23 #   - Every input format supported by yt-dlp,
  24 #     when using a ".page" instead of a ".feed" file.
  25 #   It downloads much more quickly than simply
  26 #   running those commands directly on the feed
  27 #   or on each entries of the feed, because
  28 #   to decide whether a podcast has already been downloaded or not,
  29 #   it relies only on the feed's content and on a ".downloaded" file
  30 #   it creates next to those ".feed" files;
  31 #   avoiding the cost of network activity when not necessary.
  32 # Environment:
  33 #   - $PODL_SKIP_DOWNLOAD: if set, skip the download command
  34 #     but still register the entry in ".downloaded".
  35 #     Useful when adding the feed if you only want
  36 #     a few entries from the feed:
  37 #     run PODL_SKIP_DOWNLOAD=set podl, then edit ".downloaded"
  38 #     to remove the entries you want, then run podl again.
  39 #     This trick does not work with ".page" downloads.
  40 #   - $YT: options passed to yt-dlp.
  41 #   - $PODL_XTRACE: if set, enables set -x on the generated commands.
  42 # Files:
  43 #   - ".yt-dlp": optional yt-dlp config,
  44 #     (looked up in parent directories).
  45 #   - ".url.xpath": custom XPath selector for the URL
  46 #     (looked up in parent directories).
  47 # SPDX-License-Identifier: GPL-3.0-or-later
  48 # Bugs: Julien Moutinho <julm+podl@sourcephile.fr>
  49 set -eu
  50
  51 look_up() {
  52   local key=$1; shift
  53   (
  54   while test "$PWD" != / -a "$PWD" != //
  55   do
  56     test ! -f "$key" || {
  57       "$@" "$PWD/$key"
  58       return
  59     }
  60     cd ..
  61   done
  62   )
  63 }
  64
  65 find -H "$@" -type f '(' -name .feed -o -name .page ')' |
  66 sort |
  67 while IFS= read -r found; do
  68   IFS=$(printf ' \n\r')
  69   src="$(readlink -e "$found")"
  70   dst="$(dirname "$found")"
  71   dst="$(readlink -e "$dst")"
  72   export dst
  73   echo >&2 "$dst"
  74   (
  75   cd "$dst"
  76   export YT="$(look_up .yt-dlp printf -- '--config-location %s') ${YT-}"
  77   case $found in
  78    (*/.page)
  79     yt-dlp $YT \
  80      ${PODL_SKIP_DOWNLOAD:+--skip-download} \
  81      --download-archive .downloaded \
  82      --batch-file "$src"
  83     ;;
  84    (*/.feed)
  85     feeds=$(sed "$src" \
  86      -e 's@.*youtube\.com/channel/\([^/]\+\).*@https://www.youtube.com/feeds/videos.xml?channel_id=\1@' \
  87      -e 's@.*youtube\.com/user/\([^/]\+\).*@https://www.youtube.com/feeds/videos.xml?user=\1@' \
  88      -e 's@.*youtube\.com.*list=\([^&]\+\).*@https://www.youtube.com/feeds/videos.xml?playlist_id=\1@' \
  89     )
  90     for feed in $feeds; do
  91       (
  92       file=$(mktemp)
  93       trap "rm -f '$file'" EXIT
  94       curl -Ls "$feed" -o "$file"
  95       case $(file --mime-type "$file" | cut -f 2 -d :) in
  96         (' 'text/html)
  97           export html_match_xpath="$(look_up .html.match.xpath cat)"
  98           export html_url_xpath="$(look_up .html.url.xpath cat)"
  99           xml format --html <"$file" 2>/dev/null |
 100           xml select --text \
 101            -t -m "${html_match_xpath:-'//a'}" \
 102            -o "url='" -v "translate(${html_url_xpath:-"@href"},\"'$IFS\",\"’   \")" -o "'" -n \
 103            -o '
 104             test -z "$url" ||
 105             grep -qxF "url $url" .downloaded || {
 106               if test ! "${skip_download:+set}"
 107               then
 108                 yt-dlp $YT "$url"
 109               fi
 110               { flock --exclusive 3
 111                 echo >&3 "url $url"
 112               } 3>>.downloaded
 113             }
 114            ' -n
 115           ;;
 116         (' 'text/xml)
 117           export url_xpath="$(look_up .url.xpath cat)"
 118           xml select <"$file" --text \
 119            -N atom="http://www.w3.org/2005/Atom" \
 120            -N yt="http://www.youtube.com/xml/schemas/2015" \
 121            -N mrss="http://search.yahoo.com/mrss/" \
 122            -t -m "/rss/channel/item" \
 123            -o "title='" -v "translate(translate(title,'\"','_'),\"'/:?&|$IFS\",\"’_____   \")" -o "'" -n \
 124            -o "guid='" -v "translate(translate(guid,'\"','_'),\"'$IFS\",\"’   \")" -o "'" -n \
 125            -o "url='" -v "translate(${url_xpath:-"enclosure[1]/@url"},\"'$IFS\",\"’   \")" -o "'" -n \
 126            -o "published='" -v "translate(pubDate,\"'$IFS\",\"’   \")" -o "'" -n \
 127            -o '
 128             file=${url##*/}
 129             file=${file%%\#*}
 130             file=${file%%\?*}
 131             # remove leading whitespace characters
 132             title="${title#"${title%%[![:space:]]*}"}"
 133             # remove trailing whitespace characters
 134             title="${title%"${title##*[![:space:]]}"}"
 135             test -z "$url" ||
 136             grep -qxF -e "url $url" -e "guid $guid" .downloaded || {
 137               published=$(date +%Y-%m-%d -d "$published")
 138               echo >&2 "$dst/$published - $title"
 139               if test ! "${PODL_SKIP_DOWNLOAD:+set}"
 140               then
 141                 yt-dlp $YT \
 142                  --output "$published - ${title//%/%%}.%(ext)s" \
 143                  "$url"
 144               fi
 145               { flock --exclusive 3
 146                 echo >&3 "guid $guid"
 147                 echo >&3 "url $url"
 148               } 3>>.downloaded
 149             }
 150            ' -n -b \
 151            -t -m "/atom:feed/atom:entry[yt:videoId]" \
 152            -o "title='" -v "translate(translate(atom:title,'\"','_'),\"'/:?&|$IFS\",\"’_____   \")" -o "'" -n \
 153            -o "url='" -v "translate(${url_xpath:-"atom:link[@rel='alternate']/@href"},\"'$IFS\",\"’   \")" -o "'" -n \
 154            -o "published='" -v "translate(atom:published,\"'$IFS\",\"’   \")" -o "'" -n \
 155            -o "id='" -v "translate(yt:videoId,\"'$IFS\",\"’   \")" -o "'" -n \
 156            -o '
 157             # remove leading whitespace characters
 158             title="${title#"${title%%[![:space:]]*}"}"
 159             # remove trailing whitespace characters
 160             title="${title%"${title##*[![:space:]]}"}"
 161             grep -qxF "youtube $id" .downloaded || {
 162               published=$(date +%Y-%m-%d -d "$published")
 163               echo >&2 "$dst/$published - $title.$id"
 164               if test "${PODL_SKIP_DOWNLOAD:+set}"
 165               then
 166                 { flock --exclusive 3
 167                   echo >&3 "youtube $id"
 168                 } 3>>.downloaded
 169               else
 170                 yt-dlp $YT \
 171                  --download-archive .downloaded \
 172                  --output "%(release_date>%Y-%m-%d,upload_date>%Y-%m-%d|$published)s - ${title//%/%%}.%(id)s.%(format_id)s.%(ext)s" \
 173                  "$url"
 174               fi
 175             }
 176            ';;
 177       esac |
 178       "$SHELL" -seu${PODL_XTRACE:+x}
 179       )
 180     done;;
 181   esac
 182   )
 183 done
 184
 185