FU::Log: Add logger and basic integration with FU

FU.pm

@@ -2,7 +2,9 @@ package FU 0.1;
 use v5.36;
 use Carp 'confess', 'croak';
 use IO::Socket;
-use POSIX;
+use POSIX ();
+use Time::HiRes 'time';
+use FU::Log 'log_write';
 use FU::Util;
 
 
@@ -21,6 +23,12 @@ our $REQ = {}; # Internal request-local data
 our $fu = bless {}, 'FU::obj'; # App request-local data
 sub fu() { $fu }
 
+FU::Log::capture_warn(1);
+FU::Log::set_fmt(sub($msg) {
+    FU::Log::default_fmt($msg,
+        fu->path && fu->method ? fu->method.' '.fu->path.(fu->query?'?'.fu->query:'') : '[init]',
+    );
+});
 
 sub debug            { state $v = 0; $v = $_[0] if @_; $v }
 sub log_slow_pages   { state $v = 0; $v = $_[0] if @_; $v }
@@ -235,7 +243,8 @@ sub _read_req($c) {
         # All other errors suggest a misconfigured web server, anyway.
         if ($r == -6) { fu->error(400, 'Client disconnect before request was read') }
         elsif ($r) {
-            warn $r == -1 ? "Unexpected EOF while reading from FastCGI socket\n"
+            log_write
+                 $r == -1 ? "Unexpected EOF while reading from FastCGI socket\n"
                : $r == -2 ? "I/O error while reading from FastCGI socket\n"
                : $r == -3 ? "FastCGI protocol error\n"
                : $r == -4 ? "Too long FastCGI parameter\n"
@@ -246,6 +255,9 @@ sub _read_req($c) {
         fu->error(400, 'Invalid request') if !$REQ->{method} || $REQ->{method} !~ /^$method_re$/ || !$REQ->{path};
     } else {
         _read_req_http($c->{client_sock}, $REQ);
+
+        # Silly hack to clear ${^LAST_FH}, removes the "at <GEN#> line $n" from warn()
+        open my $bullshit, '<', \"\n"; <$bullshit>;
     }
 
     # The HTTP reader above and the FastCGI XS reader operate on bytes.
@@ -264,7 +276,16 @@ sub _is_done($e) { ref $@ eq 'FU::err' && $@->[0] == 200 }
 sub _log_err($e) {
     return if !$e;
     return if !debug && ref $@ eq 'FU::err' && $@->[0] != 500;
-    warn $e =~ /\n$/ ? $e : "$e\n";
+    if (!$REQ->{full_err} && (ref $@ ne 'FU::err' || $@->[0] == 500)) {
+        $REQ->{full_err}++;
+        log_write join "\n",
+            'IP: '.($REQ->{ip}||'-'),
+            'Headers:', (map "  $_: $REQ->{hdr}{$_}", sort keys $REQ->{hdr}->%*),
+            'ERROR:', $e =~ s/(^|\n)/  /rg;
+            # TODO: decoded body, if we have that.
+    } else {
+        log_write $e;
+    }
 }
 
 sub _do_req($c) {
@@ -276,6 +297,7 @@ sub _do_req($c) {
 
     my $ok = eval {
         _read_req $c;
+        $REQ->{trace_start} = time;
 
         for my $h (@before_request) { $h->() }
 
@@ -318,7 +340,15 @@ sub _do_req($c) {
         } || _err_500();
     }
 
+    $REQ->{trace_end} = time;
     fu->_flush($c->{fcgi_obj} || $c->{client_sock});
+
+    my $proc_ms = (time - $REQ->{trace_start}) * 1000;
+    log_write(sprintf "%.0fms %s-%s %s-%d\n", $proc_ms,
+        $REQ->{status}, ($REQ->{reshdr}{'content-type'}//'-') =~ s/;.+$//r,
+        $REQ->{reshdr}{'content-encoding'}//'bytes', length($REQ->{resbody}),
+        # TODO: SQL timings
+    ) if FU::debug || $proc_ms > (FU::log_slow_pages||1e10);
 }
 
 
@@ -338,7 +368,7 @@ sub _run_loop($c) {
         $c->{fcgi_obj} ||= $c->{listen_proto} eq 'fcgi' && FU::fcgi::new(fileno $c->{client_sock}, $c->{proc});
 
         if ($c->{monitor} && _monitor) {
-            warn "File change detected, restarting process.\n" if debug;
+            log_write "File change detected, restarting process.\n" if debug;
             passclient;
         }
 
@@ -384,7 +414,7 @@ sub _supervisor($c) {
             $err = 1 if POSIX::WIFEXITED($?) && POSIX::WEXITSTATUS($?) != 0;
             if (!$err && (!$childs{$pid} || $childs{$pid} != 2)) {
                 $err = 1;
-                warn "Script exited before calling FU::run()\n";
+                log_write "Script exited before calling FU::run()\n";
             }
             delete $childs{$pid};
         }
@@ -459,7 +489,9 @@ sub _spawn {
             $c{max_reqs} = $1 if /^--max-reqs=([0-9]+)$/;
             debug 1 if /^--debug$/;
             debug 0 if /^--no-debug$/;
+            $ENV{FU_LOG_FILE} = $1 if /^--log-file=(.+)$/;
         }
+        FU::Log::set_file($ENV{FU_LOG_FILE}) if $ENV{FU_LOG_FILE};
     };
 
     # Single process, no need for a supervisor
@@ -493,7 +525,7 @@ sub _spawn {
                 LocalAddr => $addr,
             )
         ) or die "Unable to create listen socket: $!\n";
-        print "Listening on $addr\n" if debug;
+        log_write "Listening on $addr\n" if debug;
     }
 
     if ($need_supervisor) {
@@ -753,6 +785,8 @@ standalone and can be used independently of the framework:
 
 =item * L<FU::XMLWriter> - Dynamic XML generation, easy and fast.
 
+=item * L<FU::Log> - Global logger.
+
 =back
 
 Note that everything in this distribution requires a moderately recent version
@@ -944,6 +978,12 @@ and then can never hurt.
 
 Set the initial value for C<FU::debug>.
 
+=item FU_LOG_FILE=path
+
+=item --log-file=path
+
+Set the initial value for C<FU::Log::set_file()>.
+
 =item LISTEN_FD=num
 
 =item LISTEN_PROTO=http/fcgi