Load each logger that the configuration names before using it

tPSGI called new on every class in loggers without loading it.  It builds
its log the first time it logs, and new() logs while it is still loading the
routers, so a logger that an application ships beside its router was never
loaded by then.  Naming one stopped the server with "Can't locate object
method new".  Load each by name with Module::Runtime, which also refuses a
name that is not a module name.

Building the log moves into _build_log, so that a test can build it more
than once.  log() still keeps the first one.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

Makefile.PL

@@ -36,6 +36,7 @@ WriteMakefile(
         "Linux::Perl::inotify" => "0",
         "List::Util" => "0",
         "Log::Dispatch" => "0",
+        "Module::Runtime" => "0",
         "Log::Dispatch::FileRotate" => "0",
         "Log::Dispatch::Screen" => "0",
         "Mojo::File" => "0",
@@ -51,6 +52,7 @@ WriteMakefile(
     TEST_REQUIRES => {
         "File::Temp" => "0",
         "Test2::V0"  => "0",
+        "Test2::Plugin::NoWarnings" => "0",
     },
     test => {TESTS => 't/*.t'}
 );

Readme.md

@@ -23,7 +23,7 @@ Obeys ~/.tpsgi.ini -- this is what will control all the custom aspects mentioned
     custom_log  : Custom location for default (rotated) log
     routers     : Router module(s), separate with comma.  Relative to TPSGI install dir.
     indices     : Dirindex files.  In addition to index.html, index.htm, index.cgi
-    loggers     : Logger module(s), separate with comma
+    loggers     : Logger module(s), separate with comma.  Each is a Log::Dispatch::Output class.  tPSGI loads it by name, so it can live beside a router
     auth        : Authentication module
     domain      : Domain name of the application, used by things like service files
     basedir     : Directory you want to chdir into on startup. Relative to TPSGI install dir.  Default '.'

bin/tpsgi

@@ -23,7 +23,7 @@ tpsgi obeys a config file, ~/.tpsgi.ini which is in Config::Simple (key=value) f
     custom_log  # Custom location for default (rotated) log
     routers     # Router module(s), separate with comma.  Relative to TPSGI install dir.
     indices     # Dirindex files.  In addition to index.html, index.htm, index.cgi
-    loggers     # Logger module(s), separate with comma
+    loggers     # Logger module(s), separate with comma.  Loaded by name, from beside a router or @INC
     auth        # Authentication module
     domain      # Domain name of the application, used by things like service files
     basedir     # Directory you want to chdir into on startup. Relative to TPSGI install dir.  Default '.'

lib/TPSGI.pm

@@ -35,6 +35,7 @@ use File::Copy;
 use Cwd qw{abs_path};
 
 use File::Basename qw{dirname basename};
+use Module::Runtime();
 use Log::Dispatch;
 use Log::Dispatch::Screen;
 use Log::Dispatch::FileRotate;
@@ -92,7 +93,11 @@ sub log {
     my $self = shift;
 
     state $log;
-    return $log if $log;
+    return $log //= $self->_build_log();
+}
+
+sub _build_log {
+    my $self = shift;
 
     my $LOGNAME = $self->{log_name};
     my $LOGDIR  = $self->{log_dir};
@@ -119,11 +124,14 @@ sub log {
         min_level => $LEVEL,
     );
 
-    $log = Log::Dispatch->new();
+    my $log = Log::Dispatch->new();
     $log->add($rotate);
     $log->add($screen);
+
+    # The first line is logged while new() is still loading the routers, so a
+    # logger that an application ships beside its router is not loaded yet.
     foreach my $logger ( @{ $self->{loggers} } ) {
-        $log->add( $logger->new( min_level => $LEVEL, log_dir => $LOGDIR ) );
+        $log->add( Module::Runtime::use_module($logger)->new( min_level => $LEVEL, log_dir => $LOGDIR ) );
     }
 
     $log->info( $self->_log("Opening Log $LOGNAME at $LEVEL level") );

t/loggers.t

@@ -0,0 +1,75 @@
+use strict;
+use warnings;
+
+use Test2::V0;
+use Test2::Plugin::NoWarnings;
+
+use Cwd            qw{abs_path};
+use File::Path     qw{make_path};
+use File::Temp     qw{tempdir};
+use File::Basename qw{dirname};
+
+use lib dirname( abs_path(__FILE__) ) . '/../lib';
+
+use TPSGI;
+
+# A logger named in the configuration is a class that nothing has loaded yet.
+# An application ships it beside its router, and TPSGI logs its first line
+# while it is still loading that router.
+my $dir = tempdir( CLEANUP => 1 );
+my $lib = "$dir/lib";
+make_path("$lib/Test/Logger");
+
+open( my $fh, '>', "$lib/Test/Logger/Capture.pm" ) or die "Cannot write the test logger: $!";
+print $fh <<'LOGGER';
+package Test::Logger::Capture;
+use strict;
+use warnings;
+use parent qw{Log::Dispatch::Output};
+
+our @lines;
+our %given;
+
+sub new {
+    my ( $class, %p ) = @_;
+    %given = %p;
+    my $self = bless {}, $class;
+    $self->_basic_init( name => 'capture', min_level => $p{min_level} );
+    return $self;
+}
+
+sub log_message {
+    my ( $self, %p ) = @_;
+    push( @lines, $p{message} );
+    return;
+}
+
+1;
+LOGGER
+close($fh);
+
+push( @INC, $lib );
+
+my $tpsgi = bless(
+    {
+        log_name => "$dir/tpsgi.log",
+        log_dir  => $dir,
+        verbose  => 0,
+        loggers  => ['Test::Logger::Capture'],
+        ip       => '0.0.0.0',
+    },
+    'TPSGI'
+);
+
+ok( lives { $tpsgi->log }, 'a logger class that nothing loaded is loaded by name' ) or note $@;
+
+no warnings 'once';
+is( $Test::Logger::Capture::given{log_dir},   $dir,   'it is handed the log directory' );
+is( $Test::Logger::Capture::given{min_level}, 'info', 'and the level' );
+like( \@Test::Logger::Capture::lines, [qr/Opening Log/], 'and it receives the lines that the file gets' );
+
+# The name becomes a path to load, so only a module name is one.
+my $refusing = bless( { %$tpsgi, loggers => ['../../etc/passwd'] }, 'TPSGI' );
+like( dies { TPSGI::_build_log($refusing) }, qr/not a module name/, 'a logger that is not a module name is refused' );
+
+done_testing();