[#171] Log files now rotate at 10MB up to seven times

Netdisco/Changes

@@ -1,3 +1,9 @@
+2.030001 - 2015-01-08
+
+  [NEW FEATURES]
+
+  * [#171] Log files now rotate at 10MB up to seven times
+
 2.030000 - 2015-01-08
 
   [NEW FEATURES]

Netdisco/bin/netdisco-daemon

@@ -41,6 +41,7 @@ BEGIN {
 
 use Daemon::Control;
 use Filesys::Notify::Simple;
+use File::Copy;
 
 use App::Netdisco::Environment;
 my $config = ($ENV{PLACK_ENV} || $ENV{DANCER_ENVIRONMENT}) .'.yml';
@@ -50,6 +51,7 @@ my @args = (scalar @ARGV > 1 ? @ARGV[1 .. $#ARGV] : ());
 
 my $log_dir = dir($home, 'logs');
 mkdir $log_dir if ! -d $log_dir;
+my $log_file = file($log_dir, 'netdisco-daemon.log');
 
 my $uid = (stat($netdisco->stringify))[4] || 0;
 my $gid = (stat($netdisco->stringify))[5] || 0;
@@ -59,25 +61,26 @@ Daemon::Control->new({
   program  => \&restarter,
   program_args => [@args],
   pid_file => file($home, 'netdisco-daemon.pid'),
-  stderr_file => file($log_dir, 'netdisco-daemon.log'),
+  stderr_file => $log_file,
-  stdout_file => file($log_dir, 'netdisco-daemon.log'),
+  stdout_file => $log_file,
   redirect_before_fork => 0,
   uid => $uid, gid => $gid,
 })->run;
 
 # the guts of this are borrowed from Plack::Loader::Restarter - many thanks!!
+my $child = 0;
 
 sub restarter {
   my ($daemon, @program_args) = @_;
   $0 = 'netdisco-daemon';
 
-  my $child = fork_and_start($daemon, @program_args);
+  $child = fork_and_start($daemon, @program_args);
   exit(1) unless $child;
 
-  my $watcher = Filesys::Notify::Simple->new([$ENV{DANCER_ENVDIR}]);
+  my $watcher = Filesys::Notify::Simple->new([$ENV{DANCER_ENVDIR}, $log_dir]);
   warn "config watcher: watching $ENV{DANCER_ENVDIR} for updates.\n";
 
-  local $SIG{TERM} = sub { signal_child('TERM', $child); exit(0); };
+  local $SIG{TERM} = sub { $child = signal_child('TERM', $child); exit(0); };
 
   while (1) {
       my @restart;
@@ -85,19 +88,33 @@ sub restarter {
       # this is blocking
       $watcher->wait(sub {
           my @events = @_;
-          @events = grep {file($_->{path})->basename eq $config} @events;
+          @events = grep {$_->{path} eq $log_file or
+                          file($_->{path})->basename eq $config} @events;
           return unless @events;
           @restart = @events;
       });
 
+      my ($hupit, $rotate) = (0, 0);
       next unless @restart;
-      warn "-- $_->{path} updated.\n" for @restart;
 
+      foreach my $f (@restart) {
+          if ($f->{path} eq $log_file) {
+              ++$rotate;
+          }
+          else {
+              warn "-- $f->{path} updated.\n";
+              ++$hupit;
+          }
+      }
+
+      rotate_logs($child, $daemon, @program_args) if $rotate;
+      if ($hupit) {
           signal_child('TERM', $child);
           $child = fork_and_start($daemon, @program_args);
           exit(1) unless $child;
       }
   }
+}
 
 sub fork_and_start {
   my ($daemon, @daemon_args) = @_;
@@ -121,6 +138,36 @@ sub signal_child {
   waitpid($pid, 0);
 }
 
+sub rotate_logs {
+  my $child = shift;
+
+  return unless (-f $log_file) and
+    ((-s $log_file) > (10 * 1024768));
+
+  my @files = glob file($log_dir, '*');
+  foreach my $f (reverse sort @files) {
+      next unless $f =~ m/$log_file\.(\d)$/;
+      my $pos = $1;
+      unlink $f if $pos == 7;
+      my $next = $pos + 1;
+      (my $newf = $f) =~ s/\.$pos$/.$next/;
+      rename $f, $newf;
+  }
+
+  # if the log file's about 10M then the race condition in copy/truncate
+  # has a low probability. if the file's larger, then we rename and kill
+  if ((-s $log_file) > (11 * 1024768)) {
+      rename $log_file, $log_file .'.1';
+      signal_child('TERM', $child);
+      $child = fork_and_start(@_);
+      exit(1) unless $child;
+  }
+  else {
+      copy $log_file, $log_file .'.1';
+      truncate $log_file, 0;
+  }
+}
+
 =head1 NAME
 
 netdisco-daemon - Job Control Daemon for Netdisco

Netdisco/bin/netdisco-web

@@ -42,6 +42,7 @@ BEGIN {
 use Daemon::Control;
 use Filesys::Notify::Simple;
 use IO::File;
+use File::Copy;
 
 use App::Netdisco::Environment;
 my $config = ($ENV{PLACK_ENV} || $ENV{DANCER_ENVIRONMENT}) .'.yml';
@@ -92,7 +93,7 @@ sub restarter {
   my $child = fork_and_start($daemon, @program_args);
   exit(1) unless $child;
 
-  my $watcher = Filesys::Notify::Simple->new([$ENV{DANCER_ENVDIR}]);
+  my $watcher = Filesys::Notify::Simple->new([$ENV{DANCER_ENVDIR}, $log_dir]);
   warn "config watcher: watching $ENV{DANCER_ENVDIR} for updates.\n";
 
   # TODO: starman also supports TTIN,TTOU,INT,QUIT
@@ -105,15 +106,27 @@ sub restarter {
       # this is blocking
       $watcher->wait(sub {
           my @events = @_;
-          @events = grep {file($_->{path})->basename eq $config} @events;
+          @events = grep {$_->{path} eq $log_file or
+                          file($_->{path})->basename eq $config} @events;
           return unless @events;
           @restart = @events;
       });
 
+      my ($hupit, $rotate) = (0, 0);
       next unless @restart;
-      warn "-- $_->{path} updated.\n" for @restart;
 
-      signal_child('HUP', $child);
+      foreach my $f (@restart) {
+          if ($f->{path} eq $log_file) {
+              ++$rotate;
+          }
+          else {
+              warn "-- $f->{path} updated.\n";
+              ++$hupit;
+          }
+      }
+
+      rotate_logs($child) if $rotate;
+      signal_child('HUP', $child) if $hupit;
   }
 }
 
@@ -139,6 +152,34 @@ sub signal_child {
   waitpid($pid, 0);
 }
 
+sub rotate_logs {
+  my $child = shift;
+
+  return unless (-f $log_file) and
+    ((-s $log_file) > (10 * 1024768));
+
+  my @files = glob file($log_dir, '*');
+  foreach my $f (reverse sort @files) {
+      next unless $f =~ m/$log_file\.(\d)$/;
+      my $pos = $1;
+      unlink $f if $pos == 7;
+      my $next = $pos + 1;
+      (my $newf = $f) =~ s/\.$pos$/.$next/;
+      rename $f, $newf;
+  }
+
+  # if the log file's about 10M then the race condition in copy/truncate
+  # has a low probability. if the file's larger, then we rename and kill
+  if ((-s $log_file) > (15 * 1024768)) {
+      rename $log_file, $log_file .'.1';
+      signal_child('HUP', $child);
+  }
+  else {
+      copy $log_file, $log_file .'.1';
+      truncate $log_file, 0;
+  }
+}
+
 =head1 NAME
 
 netdisco-web - Web Application Server for Netdisco