X-Git-Url: http://www.git.stargrave.org/?a=blobdiff_plain;f=lib%2FPublicInbox%2FWwwStatic.pm;h=e1f536f3f21c1d7ce63ea74f140d2646fb1284b1;hb=b99e2465205a8f27801066b1e914bd4091406fa2;hp=76e50c789b7336a653e99de9e46afbe67dee9203;hpb=07d0e2d336d4697c3284fe3dd59dae0583984e23;p=public-inbox.git

diff --git a/lib/PublicInbox/WwwStatic.pm b/lib/PublicInbox/WwwStatic.pm
index 76e50c78..e1f536f3 100644
--- a/lib/PublicInbox/WwwStatic.pm
+++ b/lib/PublicInbox/WwwStatic.pm
@@ -1,9 +1,55 @@
 # Copyright (C) 2016-2019 all contributors <meta@public-inbox.org>
 # License: AGPL-3.0+ <https://www.gnu.org/licenses/agpl-3.0.txt>
 
+# This package can either be a PSGI response body for a static file
+# OR a standalone PSGI app which returns the above PSGI response body
+# (or an HTML directory listing).
+#
+# It encapsulates the "autoindex", "index", and "gzip_static"
+# functionality of nginx.
 package PublicInbox::WwwStatic;
 use strict;
-use Fcntl qw(:seek);
+use parent qw(Exporter);
+use bytes ();
+use Fcntl qw(SEEK_SET O_RDONLY O_NONBLOCK);
+use POSIX qw(strftime);
+use HTTP::Date qw(time2str);
+use HTTP::Status qw(status_message);
+use Errno qw(EACCES ENOTDIR ENOENT);
+use URI::Escape qw(uri_escape_utf8);
+use PublicInbox::Hval qw(ascii_html);
+use Plack::MIME;
+our @EXPORT_OK = qw(@NO_CACHE r path_info_raw);
+
+our @NO_CACHE = ('Expires', 'Fri, 01 Jan 1980 00:00:00 GMT',
+		'Pragma', 'no-cache',
+		'Cache-Control', 'no-cache, max-age=0, must-revalidate');
+
+our $STYLE = <<'EOF';
+<style>
+@media screen {
+	*{background:#000;color:#ccc}
+	a{color:#69f;text-decoration:none}
+	a:visited{color:#96f}
+}
+@media screen AND (prefers-color-scheme:light) {
+	*{background:#fff;color:#333}
+	a{color:#00f;text-decoration:none}
+	a:visited{color:#808}
+}
+</style>
+EOF
+
+$STYLE =~ s/^\s*//gm;
+$STYLE =~ tr/\n//d;
+
+sub r ($;$) {
+	my ($code, $msg) = @_;
+	$msg ||= status_message($code);
+	[ $code, [ qw(Content-Type text/plain), 'Content-Length', length($msg),
+		@NO_CACHE ],
+	  [ $msg ] ]
+}
 
 sub prepare_range {
 	my ($env, $in, $h, $beg, $end, $size) = @_;
@@ -35,7 +81,9 @@ sub prepare_range {
 		if ($len <= 0) {
 			$code = 416;
 		} else {
-			sysseek($in, $beg, SEEK_SET) or return [ 500, [], [] ];
+			if ($in) {
+				sysseek($in, $beg, SEEK_SET) or return r(500);
+			}
 			push @$h, qw(Accept-Ranges bytes Content-Range);
 			push @$h, "bytes $beg-$end/$size";
 
@@ -43,63 +91,228 @@ sub prepare_range {
 			$env->{'psgix.no-compress'} = 1;
 		}
 	}
+	if ($code == 416) {
+		push @$h, 'Content-Range', "bytes */$size";
+		return [ 416, $h, [] ];
+	}
 	($code, $len);
 }
 
-sub response {
+# returns a PSGI arrayref response iff .gz and non-.gz mtimes match
+sub try_gzip_static ($$$$) {
 	my ($env, $h, $path, $type) = @_;
-	return unless -f $path && -r _; # just in case it's a FIFO :P
+	return unless ($env->{HTTP_ACCEPT_ENCODING} // '') =~ /\bgzip\b/i;
+	my $mtime;
+	return unless -f $path && defined(($mtime = (stat(_))[9]));
+	my $gz = "$path.gz";
+	return unless -f $gz && (stat(_))[9] == $mtime;
+	my $res = response($env, $h, $gz, $type);
+	return if ($res->[0] > 300 || $res->[0] < 200);
+	push @{$res->[1]}, qw(Cache-Control no-transform Content-Encoding gzip);
+	$res;
+}
+
+sub response ($$$;$) {
+	my ($env, $h, $path, $type) = @_;
+	$type //= Plack::MIME->mime_type($path) // 'application/octet-stream';
+	if ($path !~ /\.gz\z/i) {
+		if (my $res = try_gzip_static($env, $h, $path, $type)) {
+			return $res;
+		}
+	}
+
+	my $in;
+	if ($env->{REQUEST_METHOD} eq 'HEAD') {
+		return r(404) unless -f $path && -r _; # in case it's a FIFO :P
+	} else { # GET, callers should've already filtered out other methods
+		if (!sysopen($in, $path, O_RDONLY|O_NONBLOCK)) {
+			return r(404) if $! == ENOENT || $! == ENOTDIR;
+			return r(403) if $! == EACCES;
+			return r(500);
+		}
+		return r(404) unless -f $in;
+	}
+	my $size = -s _; # bare "_" reuses "struct stat" from "-f" above
+	my $mtime = time2str((stat(_))[9]);
+
+	if (my $ims = $env->{HTTP_IF_MODIFIED_SINCE}) {
+		return [ 304, [], [] ] if $mtime eq $ims;
+	}
 
-	# TODO: If-Modified-Since and Last-Modified?
-	open my $in, '<', $path or return;
-	my $size = -s $in;
 	my $len = $size;
 	my $code = 200;
 	push @$h, 'Content-Type', $type;
 	if (($env->{HTTP_RANGE} || '') =~ /\bbytes=([0-9]*)-([0-9]*)\z/) {
 		($code, $len) = prepare_range($env, $in, $h, $1, $2, $size);
-		if ($code == 416) {
-			push @$h, 'Content-Range', "bytes */$size";
-			return [ 416, $h, [] ];
-		}
+		return $code if ref($code);
 	}
-	push @$h, 'Content-Length', $len;
-	my $body = bless {
+	push @$h, 'Content-Length', $len, 'Last-Modified', $mtime;
+	my $body = $in ? bless {
 		initial_rd => 65536,
 		len => $len,
 		in => $in,
 		path => $path,
 		env => $env,
-	}, __PACKAGE__;
+	}, __PACKAGE__ : [];
 	[ $code, $h, $body ];
 }
 
-# called by PSGI servers:
+# called by PSGI servers on each response chunk:
 sub getline {
 	my ($self) = @_;
-	my $len = $self->{len};
-	return if $len == 0;
+	my $len = $self->{len} or return; # undef, tells server we're done
 	my $n = delete($self->{initial_rd}) // 8192;
 	$n = $len if $len < $n;
 	my $r = sysread($self->{in}, my $buf, $n);
-	if (!defined $r) {
-		$self->{env}->{'psgi.errors'}->print(
-			"$self->{path} read error: $!\n");
-	} elsif ($r > 0) { # success!
+	if (defined $r && $r > 0) { # success!
 		$self->{len} = $len - $r;
 		return $buf;
-	} else {
-		$self->{env}->{'psgi.errors'}->print(
-			"$self->{path} EOF with $len bytes left\n");
 	}
+	my $m = defined $r ? "EOF with $len bytes left" : "read error: $!";
+	die "$self->{path} $m, dropping client socket\n";
+}
+
+sub close {} # noop, called by PSGI server, just let everything go out-of-scope
+
+# OO interface for use as a Plack app
+sub new {
+	my ($class, %opt) = @_;
+	my $index = $opt{'index'} // [ 'index.html' ];
+	$index = [ $index ] if defined($index) && ref($index) ne 'ARRAY';
+	$index = undef if scalar(@$index) == 0;
+	my $style = $opt{style};
+	if (defined $style) {
+		$style = \$style unless ref($style);
+	}
+	my $docroot = $opt{docroot};
+	die "`docroot' not set" unless defined($docroot) && $docroot ne '';
+	bless {
+		docroot => $docroot,
+		index => $index,
+		autoindex => $opt{autoindex},
+		style => $style // \$STYLE,
+	}, $class;
+}
+
+# PATH_INFO is decoded, and we want the undecoded original
+my %path_re_cache;
+sub path_info_raw ($) {
+	my ($env) = @_;
+	my $sn = $env->{SCRIPT_NAME};
+	my $re = $path_re_cache{$sn} ||= do {
+		$sn = '/'.$sn unless index($sn, '/') == 0;
+		$sn =~ s!/\z!!;
+		qr!\A(?:https?://[^/]+)?\Q$sn\E(/[^\?\#]+)!;
+	};
+	$env->{REQUEST_URI} =~ $re ? $1 : $env->{PATH_INFO};
+}
 
-	# drop the client on error
-	if (my $io = $self->{env}->{'psgix.io'}) {
-		$io->close; # this is PublicInbox::DS::close
+sub redirect_slash ($) {
+	my ($env) = @_;
+	my $url = $env->{'psgi.url_scheme'} . '://';
+	my $host_port = $env->{HTTP_HOST} //
+		"$env->{SERVER_NAME}:$env->{SERVER_PORT}";
+	$url .= $host_port . path_info_raw($env) . '/';
+	my $body = "Redirecting to $url\n";
+	[ 302, [ qw(Content-Type text/plain), 'Location', $url,
+		'Content-Length', length($body) ], [ $body ] ]
+}
+
+sub human_size ($) {
+	my ($size) = @_;
+	my $suffix = '';
+	for my $s (qw(K M G T P)) {
+		last if $size < 1024;
+		$size /= 1024;
+		if ($size <= 1024) {
+			$suffix = $s;
+			last;
+		}
 	}
-	undef;
+	sprintf('%lu', $size).$suffix;
 }
 
-sub close {} # noop, just let everything go out-of-scope
+# by default, this returns "index.html" if it exists for a given directory
+# It'll generate a directory listing, (autoindex).
+# May be disabled by setting autoindex => 0
+sub dir_response ($$$) {
+	my ($self, $env, $fs_path) = @_;
+	if (my $index = $self->{'index'}) { # serve index.html or similar
+		for my $html (@$index) {
+			my $p = $fs_path . $html;
+			my $res = response($env, [], $p);
+			return $res if $res->[0] != 404;
+		}
+	}
+	return r(404) unless $self->{autoindex};
+	opendir(my $dh, $fs_path) or do {
+		return r(404) if ($! == ENOENT || $! == ENOTDIR);
+		return r(403) if $! == EACCES;
+		return r(500);
+	};
+	my @entries = grep(!/\A\./, readdir($dh));
+	$dh = undef;
+	my (%dirs, %other, %want_gz);
+	my $path_info = $env->{PATH_INFO};
+	push @entries, '..' if $path_info ne '/';
+	for my $base (@entries) {
+		my $href = ascii_html(uri_escape_utf8($base));
+		my $name = ascii_html($base);
+		my @st = stat($fs_path . $base) or next; # unlikely
+		my ($gzipped, $uncompressed, $hsize);
+		my $entry = '';
+		my $mtime = $st[9];
+		if (-d _) {
+			$href .= '/';
+			$name .= '/';
+			$hsize = '-';
+			$dirs{"$base\0$mtime"} = \$entry;
+		} elsif (-f _) {
+			$other{"$base\0$mtime"} = \$entry;
+			if ($base !~ /\.gz\z/i) {
+				$want_gz{"$base.gz\0$mtime"} = undef;
+			}
+			$hsize = human_size($st[7]);
+		} else {
+			next;
+		}
+		# 54 = 80 - (SP length(strftime(%Y-%m-%d %k:%M)) SP human_size)
+		$hsize = sprintf('% 8s', $hsize);
+		my $pad = 54 - length($name);
+		$pad = 1 if $pad <= 0;
+		$entry .= qq(<a\nhref="$href">$name</a>) . (' ' x $pad);
+		$mtime = strftime('%Y-%m-%d %k:%M', gmtime($mtime));
+		$entry .= $mtime . $hsize;
+	}
+
+	# filter out '.gz' files as long as the mtime matches the
+	# uncompressed version
+	delete(@other{keys %want_gz});
+	@entries = ((map { ${$dirs{$_}} } sort keys %dirs),
+			(map { ${$other{$_}} } sort keys %other));
+
+	my $path_info_html = ascii_html($path_info);
+	my $body = "<html><head><title>Index of $path_info_html</title>" .
+		${$self->{style}} .
+		"</head><body><pre>Index of $path_info_html</pre><hr><pre>\n";
+	$body .= join("\n", @entries) . "</pre><hr></body></html>\n";
+	[ 200, [ qw(Content-Type text/html
+			Content-Length), bytes::length($body) ], [ $body ] ]
+}
+
+sub call { # PSGI app endpoint
+	my ($self, $env) = @_;
+	return r(405) if $env->{REQUEST_METHOD} !~ /\A(?:GET|HEAD)\z/;
+	my $path_info = $env->{PATH_INFO};
+	return r(403) if index($path_info, "\0") >= 0;
+	my (@parts) = split(m!/+!, $path_info, -1);
+	return r(403) if grep(/\A(?:\.\.)\z/, @parts) || $parts[0] ne '';
+
+	my $fs_path = join('/', $self->{docroot}, @parts);
+	return dir_response($self, $env, $fs_path) if $parts[-1] eq '';
+
+	my $res = response($env, [], $fs_path);
+	$res->[0] == 404 && -d $fs_path ? redirect_slash($env) : $res;
+}
 
 1;