forked from lix-project/lix
![Eelco Dolstra](/assets/img/avatar_default.png)
Nix expressions. To subscribe to a channel (needs to be done only once): nix-channel --add \ http://catamaran.labs.cs.uu.nl/dist/nix/channels/nixpkgs-unstable This just adds the given URL to ~/.nix-channels (which can also be edited manually). To update from all channels: nix-channel --update This fetches the latest expressions and pulls cache manifests. The default Nix expression (~/.nix-defexpr) is made to point to the conjunction of the expressions downloaded from all channels. So to update all installed derivations in the current user environment: nix-channel --update nix-env --upgrade '*' If you are really courageous, you can put this in a cronjob or something. You can subscribe to multiple channels. It is not entirely clear what happens when there are name clashes between derivations from different channels. From nix-env/main.cc it appears that the one with the lowest (highest?) hash will be used, which is pretty meaningless.
116 lines
2.8 KiB
Plaintext
Executable file
116 lines
2.8 KiB
Plaintext
Executable file
#! @perl@ -w
|
|
|
|
use strict;
|
|
|
|
|
|
# Figure out the name of the `.nix-channels' file to use.
|
|
my $home = $ENV{"HOME"};
|
|
die '$HOME not set' unless defined $home;
|
|
my $channelsList = "$home/.nix-channels";
|
|
|
|
|
|
my @channels;
|
|
|
|
|
|
# Reads the list of channels from the file $channelsList;
|
|
sub readChannels {
|
|
return if (!-f $channelsList);
|
|
open CHANNELS, "<$channelsList" or die "cannot open `$channelsList'";
|
|
while (<CHANNELS>) {
|
|
chomp;
|
|
push @channels, $_;
|
|
}
|
|
close CHANNELS;
|
|
}
|
|
|
|
|
|
# Writes the list of channels to the file $channelsList;
|
|
sub writeChannels {
|
|
open CHANNELS, ">$channelsList" or die "cannot open `$channelsList'";
|
|
foreach my $url (@channels) {
|
|
print CHANNELS "$url\n";
|
|
}
|
|
close CHANNELS;
|
|
}
|
|
|
|
|
|
# Adds a channel to the file $channelsList;
|
|
sub addChannel {
|
|
my $url = shift;
|
|
readChannels;
|
|
foreach my $url2 (@channels) {
|
|
return if $url eq $url2;
|
|
}
|
|
push @channels, $url;
|
|
writeChannels;
|
|
}
|
|
|
|
|
|
# Fetch Nix expressions and pull cache manifests from the subscribed
|
|
# channels.
|
|
sub update {
|
|
readChannels;
|
|
|
|
# Pull cache manifests.
|
|
foreach my $url (@channels) {
|
|
print "pulling cache manifest from `$url'\n";
|
|
system "@bindir@/nix-pull '$url'/MANIFEST";
|
|
die "cannot pull cache manifest from `$url'" if ($? != 0);
|
|
}
|
|
|
|
# Create a Nix expression that fetches and unpacks the channel Nix
|
|
# expressions.
|
|
|
|
my $nixExpr = "[";
|
|
|
|
foreach my $url (@channels) {
|
|
my $fullURL = "$url/nixexprs.tar.bz2";
|
|
my $hash = `@bindir@/nix-prefetch-url '$fullURL' 2> /dev/null`
|
|
or die "cannot fetch `$fullURL'";
|
|
chomp $hash;
|
|
# !!! escaping
|
|
$nixExpr .= "((import @datadir@/nix/corepkgs/fetchurl) " .
|
|
"{url = $fullURL; md5 = \"$hash\"; system = \"@system@\";}) "
|
|
}
|
|
|
|
$nixExpr .= "]";
|
|
|
|
$nixExpr =
|
|
"(import @datadir@/nix/corepkgs/channels/unpack.nix) " .
|
|
"{inputs = $nixExpr; system = \"@system@\";}";
|
|
|
|
# Instantiate and realise it.
|
|
my $storeExpr = `echo '$nixExpr' | @bindir@/nix-instantiate -`
|
|
or die "cannot instantiate Nix expression";
|
|
chomp $storeExpr;
|
|
|
|
my $outPath = `nix-store -qnfB '$storeExpr'`
|
|
or die "cannot realise store expression";
|
|
chomp $outPath;
|
|
|
|
# Make it the default Nix expression for `nix-env'.
|
|
system "@bindir@/nix-env --import '$outPath'";
|
|
die "cannot pull set default Nix expression to `$outPath'" if ($? != 0);
|
|
}
|
|
|
|
|
|
while (scalar @ARGV) {
|
|
my $arg = shift @ARGV;
|
|
|
|
if ($arg eq "--add") {
|
|
die "syntax: nix-channel --add URL" if (scalar @ARGV != 1);
|
|
addChannel (shift @ARGV);
|
|
last;
|
|
}
|
|
|
|
elsif ($arg eq "--update") {
|
|
die "syntax: nix-channel --update" if (scalar @ARGV != 0);
|
|
update;
|
|
last;
|
|
}
|
|
|
|
else {
|
|
die "unknown argument `$arg'";
|
|
}
|
|
}
|