lbussy/log_tail.php

## log_tail.php
<!--
	PHP Log Tail
	by Lee C. Bussy

	A single-page log file viewer with "tail -f" capabilities.

	Pass the name of the log file to be viewed as a URL parameter:
		log_tail.php?logFile=my.log

	For safety and to prevent breakouts, the path to the log file
	is hard-coded as $logDir.  This is compared to the concatenated
	path before reading to eliminate any "../.." shenanigans.

	The page will send a second request to itself with:
		log_tail.php?getLog=True
	The getLog parameter will cause the page to feed the log file
	into the original page.
 -->

<?php
$logDir = "/var/log"; // Prepend this path (no trailing slash)

$shortName = $_GET['logFile']; // Log file to get = ?logFile={foo}
$logPath = $logDir . "/" . $shortName;

if (isset($_GET['getLog'])) {
	$thisDirName = dirname(realpath($logPath));
	if ($thisDirName == $logDir) {
		if (is_file($logPath)) {
			echo file_get_contents($logPath);
		} else {
			echo "No log found.";
		}
	} else {
		echo "Error: Illegal input - path name.";
	}
} else {
?>

<!DOCTYPE html>
<html lang="en">
	<title>Log Viewer</title>
	<link rel="stylesheet" href="logstyle.css">
    <script
        src="https://code.jquery.com/jquery-3.6.4.min.js"
        integrity="sha256-oP6HI9z1XaZNBrJURtCoUT5SUnxFr8s3BzRl+cbzUq8="
        crossorigin="anonymous">
    </script>
	<script>
		let thisPage = window.location.pathname;
		let interval = 1000;
		var scrollLock = true;
		var readingFile = false;

		// Get logfilename from ?logFile={foo}
		const params = new Proxy(new URLSearchParams(window.location.search), {
			get: (searchParams, prop) => searchParams.get(prop),
		});
		let thisLog = params.logFile;

		$(document).ready(function(){
			$('.disableScrollLock').click(function(){
				$("html,body").clearQueue()
				$(".disableScrollLock").hide();
				$(".enableScrollLock").show();
				scrollLock = false;
			});
			$('.enableScrollLock').click(function(){
				$("html,body").clearQueue()
				$(".enableScrollLock").hide();
				$(".disableScrollLock").show();
				scrollLock = true;
			});
			setInterval(readLogFile, interval);
		});

		function readLogFile() {
			// Singleton trap
			if (! readingFile) {
				readingFile = true;
				$.get(thisPage, { getLog : "true", logFile : thisLog }, function(data) {
					data = data.replace(new RegExp("\n", "g"), "<br />");
					$("#log").html(data);
					if(scrollLock == true) { $('html,body').animate({scrollTop: $("#scrollLock").offset().top}, interval) };
				})
				.fail(function() {
					alert( "GET error (this should not be possible.)" );
				})
				.always(function() {
					readingFile = false;
				});
			}
		}
	</script>
	<body>
		<h4><?php echo "Following: " . $shortName; ?></h4>
		<div id="log"></div>
		<div id="scrollLock"> <input class="disableScrollLock" type="button" value="Disable Scroll Lock"> <input class="enableScrollLock" style="display: none;" type="button" value="Enable Scroll Lock"></div>
	</body>
</html>

<?php
}
?>

## logstyle.css
@import url(http://fonts.googleapis.com/css?family=Ubuntu);

body {
    background-color: black;
    color: white;
    font-family: 'Ubuntu', sans-serif;
    font-size: 16px;
    line-height: 20px;
}

h4 {
    background-color: black;
    color: white;
    font-size: 18px;
    line-height: 80px;
}

#log {
    position: relative;
    top: -34px;
}

#scrollLock {
    width: 2px;
    height: 2px;
    overflow: visible;
}
	<!--
	PHP Log Tail
	by Lee C. Bussy

	A single-page log file viewer with "tail -f" capabilities.

	Pass the name of the log file to be viewed as a URL parameter:
	log_tail.php?logFile=my.log

	For safety and to prevent breakouts, the path to the log file
	is hard-coded as $logDir. This is compared to the concatenated
	path before reading to eliminate any "../.." shenanigans.

	The page will send a second request to itself with:
	log_tail.php?getLog=True
	The getLog parameter will cause the page to feed the log file
	into the original page.
	-->

	<?php
	$logDir = "/var/log"; // Prepend this path (no trailing slash)

	$shortName = $_GET['logFile']; // Log file to get = ?logFile={foo}
	$logPath = $logDir . "/" . $shortName;

	if (isset($_GET['getLog'])) {
	$thisDirName = dirname(realpath($logPath));
	if ($thisDirName == $logDir) {
	if (is_file($logPath)) {
	echo file_get_contents($logPath);
	} else {
	echo "No log found.";
	}
	} else {
	echo "Error: Illegal input - path name.";
	}
	} else {
	?>

	<!DOCTYPE html>
	<html lang="en">
	<title>Log Viewer</title>
	<link rel="stylesheet" href="logstyle.css">
	<script
	src="https://code.jquery.com/jquery-3.6.4.min.js"
	integrity="sha256-oP6HI9z1XaZNBrJURtCoUT5SUnxFr8s3BzRl+cbzUq8="
	crossorigin="anonymous">
	</script>
	<script>
	let thisPage = window.location.pathname;
	let interval = 1000;
	var scrollLock = true;
	var readingFile = false;

	// Get logfilename from ?logFile={foo}
	const params = new Proxy(new URLSearchParams(window.location.search), {
	get: (searchParams, prop) => searchParams.get(prop),
	});
	let thisLog = params.logFile;

	$(document).ready(function(){
	$('.disableScrollLock').click(function(){
	$("html,body").clearQueue()
	$(".disableScrollLock").hide();
	$(".enableScrollLock").show();
	scrollLock = false;
	});
	$('.enableScrollLock').click(function(){
	$("html,body").clearQueue()
	$(".enableScrollLock").hide();
	$(".disableScrollLock").show();
	scrollLock = true;
	});
	setInterval(readLogFile, interval);
	});

	function readLogFile() {
	// Singleton trap
	if (! readingFile) {
	readingFile = true;
	$.get(thisPage, { getLog : "true", logFile : thisLog }, function(data) {
	data = data.replace(new RegExp("\n", "g"), "<br />");
	$("#log").html(data);
	if(scrollLock == true) { $('html,body').animate({scrollTop: $("#scrollLock").offset().top}, interval) };
	})
	.fail(function() {
	alert( "GET error (this should not be possible.)" );
	})
	.always(function() {
	readingFile = false;
	});
	}
	}
	</script>
	<body>
	<h4><?php echo "Following: " . $shortName; ?></h4>
	<div id="log"></div>
	<div id="scrollLock"> <input class="disableScrollLock" type="button" value="Disable Scroll Lock"> <input class="enableScrollLock" style="display: none;" type="button" value="Enable Scroll Lock"></div>
	</body>
	</html>

	<?php
	}
	?>
	@import url(http://fonts.googleapis.com/css?family=Ubuntu);

	body {
	background-color: black;
	color: white;
	font-family: 'Ubuntu', sans-serif;
	font-size: 16px;
	line-height: 20px;
	}

	h4 {
	background-color: black;
	color: white;
	font-size: 18px;
	line-height: 80px;
	}

	#log {
	position: relative;
	top: -34px;
	}

	#scrollLock {
	width: 2px;
	height: 2px;
	overflow: visible;
	}