Implemented preparatory commands

diff --git a/NOTES b/NOTES
index 561abd6b13715bb29ea9af7b17a9e06801636b74..9f3dc17de0e975b8750cad95af1685c8884c53f1 100644 (file)
--- a/NOTES
+++ b/NOTES
@@ -32,6 +32,9 @@ Known header fields:
 
 ID: <job-id>                   Identifier of the job, unique in the scope of a queue
 Subject: <subject>             Subject to be displayed to the user
+Prep: <command>                        Run <command> in a shell before the job body is executed;
+                               $HOST contains the name of the host. This is useful for
+                               example if you want to transfer data to the host by rsync.
 
 ### Status files ###
 
@@ -52,11 +55,13 @@ OK          Job finished successfully (this is usually not seen in the queue, since
                finished jobs are immediately deleted or moved to the history)
 FAILED         Job failed to execute (i.e., it returned a non-zero exit code)
 INTERR         Internal error of BEX (e.g., failed to read job prolog file)
+PREPFAIL       Preparatory commands failed (i.e., those present in Prep header field)
 
 These are present only in log files and messages sent over status FIFO:
 
 RUN            Job is running
 SEND           Sending job to the host
+PREP           Running preparatory commands (i.e., those present in Prep header field)
 
 Status codes not tied to a specific job (sent over status FIFO):
 

diff --git a/TODO b/TODO
index b2a374d4656b5a8a989a460b11706dd36e859f90..b7badfd8226458a91294c1fadcf01c8b212dd500 100644 (file)
--- a/TODO
+++ b/TODO
@@ -1,7 +1,6 @@
 - bprun: option for setting max # of running jobs
 - bprun --job
 - bprun --curses
-- rsync, rsync-only
 - Terminology: machine vs. host
 - ssh options
 - Detector of orphans (unused queue dirs, jobs on non-existent machines, non-queued jobs)

diff --git a/brun b/brun
index 324f23f6dd58c8dae0042197427503a63af3b098..3e46d4700571b07621a48ed9991863b872a21f22 100755 (executable)
--- a/brun
+++ b/brun
@@ -42,19 +42,64 @@ sub update_status($$$$;$) {
        }
 }
 
+my %pings;
+
 sub ping_machine($) {
        my ($mach) = @_;
-       return 1 unless $BEX::Config::ping_hosts;
-       update_status($mach, '-', 'PING', undef);
-       my $host = BEX::Config::host_name($mach);
-       `ping -c1 -n $host >/dev/null 2>/dev/null`;
-       return !$?;
+       if (!defined $pings{$mach}) {
+               if ($BEX::Config::ping_hosts) {
+                       update_status($mach, '-', 'PING', undef);
+                       my $host = BEX::Config::host_name($mach);
+                       `ping -c1 -n $host >/dev/null 2>/dev/null`;
+                       $pings{$mach} = !$?;
+               } else {
+                       $pings{$mach} = 1;
+               }
+       }
+       if ($pings{$mach}) {
+               return ('OK', undef);
+       } else {
+               return ('NOPING', 'Does not ping');
+       }
 }
 
-sub run_job($$$) {
+sub exit_status($) {
+       my ($s) = @_;
+       if ($s >> 8) {
+               return "with exit code " . ($s >> 8);
+       } else {
+               return "on fatal signal " . ($s & 127);
+       }
+}
+
+sub run_job_prep($$$) {
+       my ($job, $queue, $mach) = @_;
+       my $prep = $job->attr('Prep');
+       defined($prep) && $prep !~ /^\s*$/ or return 'OK';
+
+       my $jid = $job->id;
+       update_status($mach, $jid, 'PREP', $queue);
+       my $lf = $queue->log_file($mach, $jid);
+       $ENV{'HOST'} = BEX::Config::host_name($mach);
+       system 'bash', '-o', 'pipefail', '-c', "( $prep ) 2>&1 | tee -a $lf";
+       delete $ENV{'HOST'};
+       if ($?) {
+               return ('PREPFAIL', 'Preparatory command failed ' . exit_status($?));
+       } else {
+               return 'OK';
+       }
+}
+
+sub run_job_body($$$) {
        my ($job, $queue, $mach) = @_;
-       my $jid = $job->{'ID'};
+
+       if ($job->attr('body') =~ /^\s*$/s) {
+               # Shortcut if the body is empty
+               return 'OK'
+       }
+
        my $host = BEX::Config::host_name($mach);
+       my $jid = $job->id;
 
        my $tmp = $queue->temp_file($mach, $jid);
        open T, '>', $tmp or die;
@@ -66,7 +111,7 @@ sub run_job($$$) {
                print T "#!/bin/sh\n";
        }
        print T "# BEX job ", $jid, "\n";
-       print T $job->{'body'};
+       print T $job->attr('body');
        if (defined $BEX::Config::job_epilog) {
                open E, $BEX::Config::job_epilog or return ('INTERR', "Cannot open epilog: $!");
                while (<E>) { print T; }
@@ -84,12 +129,25 @@ sub run_job($$$) {
        my $lf = $queue->log_file($mach, $jid);
        system 'bash', '-o', 'pipefail', '-c', "ssh -t $host '$rtmp ; e=\$? ; rm -f $rtmp ; exit \$e' 2>&1 | tee -a $lf";
        if ($?) {
-               return ('FAILED', 'Job failed');
+               return ('FAILED', 'Job failed ' . exit_status($?));
        } else {
-               return ('OK', undef);
+               return 'OK';
        }
 }
 
+sub run_job($$$) {
+       my ($job, $queue, $mach) = @_;
+       my ($stat, $msg);
+
+       ($stat, $msg) = ping_machine($mach);
+       $stat eq 'OK' or return ($stat, $msg);
+
+       ($stat, $msg) = run_job_prep($job, $queue, $mach);
+       $stat eq 'OK' or return ($stat, $msg);
+
+       return run_job_body($job, $queue, $mach);
+}
+
 my @machines = BEX::Config::parse_machine_list(@ARGV ? @ARGV : '*');
 my $queue = BEX::Queue->new($queue_name);
 
@@ -104,7 +162,6 @@ for my $mach (@machines) {
                next;
        }
        update_status($mach, '-', 'INIT', undef);
-       my $ping;
        while (my $jid = shift @q) {
                if (defined $given_job) {
                        $jid eq $given_job or next;
@@ -119,13 +176,7 @@ for my $mach (@machines) {
                        'Time' => time,
                };
                print "### Running $jid (", $job->attr('Subject'), ") on $mach ###\n";
-               $ping //= ping_machine($mach);
-               my ($s, $msg);
-               if (!$ping) {
-                       ($s, $msg) = ('NOPING', 'Does not ping');
-               } else {
-                       ($s, $msg) = run_job($job, $queue, $mach);
-               }
+               my ($s, $msg) = run_job($job, $queue, $mach);
 
                $stat->{'Status'} = $s;
                $stat->{'Message'} = $msg;