nixpkgs/nixos/modules/testing/service-runner.nix
Eelco Dolstra 29027fd1e1 Rewrite ‘with pkgs.lib’ -> ‘with lib’
Using pkgs.lib on the spine of module evaluation is problematic
because the pkgs argument depends on the result of module
evaluation. To prevent an infinite recursion, pkgs and some of the
modules are evaluated twice, which is inefficient. Using ‘with lib’
prevents this problem.
2014-04-14 16:26:48 +02:00

114 lines
3.2 KiB
Nix

{ config, lib, pkgs, ... }:
with lib;
let
makeScript = name: service: pkgs.writeScript "${name}-runner"
''
#! ${pkgs.perl}/bin/perl -w -I${pkgs.perlPackages.FileSlurp}/lib/perl5/site_perl
use File::Slurp;
sub run {
my ($cmd) = @_;
my @args = split " ", $cmd;
my $prog;
if (substr($args[0], 0, 1) eq "@") {
$prog = substr($args[0], 1);
shift @args;
} else {
$prog = $args[0];
}
my $pid = fork;
if ($pid == 0) {
setpgrp; # don't receive SIGINT etc. from terminal
exec { $prog } @args;
die "failed to exec $prog\n";
} elsif (!defined $pid) {
die "failed to fork: $!\n";
}
return $pid;
};
sub run_wait {
my ($cmd) = @_;
my $pid = run $cmd;
die if waitpid($pid, 0) != $pid;
return $?;
};
# Set the environment. FIXME: escaping.
foreach my $key (keys %ENV) {
next if $key eq 'LOCALE_ARCHIVE';
delete $ENV{$key};
}
${concatStrings (mapAttrsToList (n: v: ''
$ENV{'${n}'} = '${v}';
'') service.environment)}
# Run the ExecStartPre program. FIXME: this could be a list.
my $preStart = '${service.serviceConfig.ExecStartPre or ""}';
if ($preStart ne "") {
print STDERR "running ExecStartPre: $preStart\n";
my $res = run_wait $preStart;
die "$0: ExecStartPre failed with status $res\n" if $res;
};
# Run the ExecStart program.
my $cmd = '${service.serviceConfig.ExecStart}';
print STDERR "running ExecStart: $cmd\n";
my $mainPid = run $cmd;
$ENV{'MAINPID'} = $mainPid;
# Catch SIGINT, propagate to the main program.
sub intHandler {
print STDERR "got SIGINT, stopping service...\n";
kill 'INT', $mainPid;
};
$SIG{'INT'} = \&intHandler;
$SIG{'QUIT'} = \&intHandler;
# Run the ExecStartPost program.
my $postStart = '${service.serviceConfig.ExecStartPost or ""}';
if ($postStart ne "") {
print STDERR "running ExecStartPost: $postStart\n";
my $res = run_wait $postStart;
die "$0: ExecStartPost failed with status $res\n" if $res;
}
# Wait for the main program to exit.
die if waitpid($mainPid, 0) != $mainPid;
my $mainRes = $?;
# Run the ExecStopPost program.
my $postStop = '${service.serviceConfig.ExecStopPost or ""}';
if ($postStop ne "") {
print STDERR "running ExecStopPost: $postStop\n";
my $res = run_wait $postStop;
die "$0: ExecStopPost failed with status $res\n" if $res;
}
exit($mainRes & 127 ? 255 : $mainRes << 8);
'';
in
{
options = {
systemd.services = mkOption {
options =
{ config, name, ... }:
{ options.runner = mkOption {
internal = true;
description = ''
A script that runs the service outside of systemd,
useful for testing or for using NixOS services outside
of NixOS.
'';
};
config.runner = makeScript name config;
};
};
};
}