core/pkgs/build-support/fetchtorrent/default.nix
2024-05-13 11:34:52 -04:00

63 lines
2.3 KiB
Nix

{ lib, runCommand, transmission_noSystemd, rqbit, writeShellScript, formats, cacert, rsync }:
let
urlRegexp = ''.*xt=urn:bt[im]h:([^&]{64}|[^&]{40}).*'';
in
{ url
, name ?
if (builtins.match urlRegexp url) == null then
"bittorrent"
else
"bittorrent-" + builtins.head (builtins.match urlRegexp url)
, config ? if (backend == "transmission") then { } else throw "json config for configuring fetchFromBitorrent only works with the transmission backend"
, hash
, backend ? "transmission"
, recursiveHash ? true
, postFetch ? ""
, postUnpack ? ""
, meta ? {}
}:
let
afterSuccess = writeShellScript "fetch-bittorrent-done.sh" ''
${postUnpack}
# Flatten the directory, so that only the torrent contents are in $out, not
# the folder name
shopt -s dotglob
mv -v $downloadedDirectory/*/* $out
rm -v -rf $downloadedDirectory
unset downloadedDirectory
${postFetch}
kill $PPID
'';
jsonConfig = (formats.json {}).generate "jsonConfig" config;
in
runCommand name {
inherit meta;
nativeBuildInputs = [ cacert ] ++ (if (backend == "transmission" ) then [ transmission_noSystemd ] else if (backend == "rqbit") then [ rqbit ] else throw "rqbit or transmission are the only available backends for fetchtorrent");
outputHashAlgo = if hash != "" then null else "sha256";
outputHash = hash;
outputHashMode = if recursiveHash then "recursive" else "flat";
# url will be written to the derivation, meaning it can be parsed and utilized
# by external tools, such as tools that may want to seed fetchtorrent calls
# in nixpkgs
inherit url;
}
(if (backend == "transmission") then ''
export HOME=$TMP
export downloadedDirectory=$out/downloadedDirectory
mkdir -p $downloadedDirectory
mkdir -p $HOME/.config/transmission
cp ${jsonConfig} $HOME/.config/transmission/settings.json
function handleChild {
# This detects failures and logs the contents of the transmission fetch
find $out
exit 0
}
trap handleChild CHLD
transmission-cli --port $(shuf -n 1 -i 49152-65535) --portmap --finish ${afterSuccess} --download-dir $downloadedDirectory --config-dir "$HOME"/.config/transmission "$url"
'' else
''
export HOME=$TMP
rqbit --disable-dht-persistence --http-api-listen-addr "127.0.0.1:$(shuf -n 1 -i 49152-65535)" download -o $out --exit-on-finish "$url"
'')