LoadModule python_module modules/mod_python.so

# Log viewer
Alias /log_viewer "C:/work/log_viewer"
<Directory "C:/work/log_viewer">
    SetHandler mod_python
    PythonHandler mod_python.publisher
    DirectoryIndex index.py
    Options FollowSymlinks
    AllowOverride None
    Order deny,allow
    Allow from all
    Satisfy all
</Directory>

import time, os
from os.path import basename

# command line utilities
SSH = 'C:/local/bin/plink.exe -C %(host)s -P %(port)s -l %(userid)s -pw %(passwd)s "%(cmd)s"'
LOCAL = '%(cmd)s'
CAT = 'cat %s'
WC = 'wc -l %s'
TAIL = 'wc -l %s && tail --lines=+%s %s'

# initial number of lines to show
INITIAL_LINES = 100

APPS_LIST = [ 
    'local_app',
    'remote_app', 
]

APPS = {
    'local_app' : {
        'name' : 'My Application - Local',
        'file' : 'C:/logs/myapp/mylog.%(date)s.txt',
        'shell' : LOCAL,
        'host' : 'localhost',
    },
    'remote_app' : { 
        'name' : 'My Application - Remote',
        'file' : '/home/myapp/mylog.%(date)s.txt',
        'shell' : SSH,
        'host' : 'apphost',
        'port' : 22,
        'userid' : 'userid',
        'passwd' : 'passwd',
     },
}

def index(app = None):
    appInfo = APPS.get(app)
    if appInfo:
        file = appInfo['file'] % { 'date' : time.strftime('%Y-%m-%d') }
    else:
        file = None

    return ''.join((html_header(app, file), html_footer()))

def download_log(req, app = None, file = None):
    appInfo = APPS.get(app)
    if not appInfo:
        return

    req.content_type = 'application/octet-stream'
    req.headers_out['Content-Disposition'] = 'attachment; filename=%s' % basename(file)
    appInfo['cmd'] =  CAT % file
    cmd =  appInfo['shell'] % appInfo 
    f = os.popen(cmd)
    for line in f:
        req.write(line)
    f.close()

def get_log(req, app = None, file = None, start_line = 1):
    try:
        start_line = int(start_line)
        if start_line < 1:
            start_line = 1
    except:
        start_line = 1
    (new_line, payload) = __get_log(app, file, start_line)
    req.content_type = 'text/xml'
    req.no_cache = True
    req.no_local_copy = True
    return """<?xml version="1.0" encoding="utf-8"?>
<ajax-response startLine="%s">
<![CDATA[%s]]>
</ajax-response>
""" % (new_line, payload)

def __get_log(app, file, start_line):
    appInfo = APPS.get(app)
    if not appInfo:
        return (1, '')

    if start_line == 1:
        appInfo['cmd'] = WC % file
        cmd = appInfo['shell'] % appInfo
        f = os.popen(cmd)
        lineCount = f.read()
        if f.close():
            return (1, '<span class="error">[ERROR] Failed to open file: %s:%s</span>' % (appInfo['host'], file))

        try:
            lineCount = int(lineCount.split()[0])
        except:
            return (1, '<span class="error">[ERROR] Failed to get a line count of: %s:%s (%s)</span>' % (appInfo['host'], file, lineCount))

        start_line = lineCount > INITIAL_LINES and (lineCount - INITIAL_LINES) or 1

    appInfo['cmd'] = TAIL % (file, start_line, file)
    cmd = appInfo['shell'] % appInfo

    f = os.popen(cmd)
    lineCount = f.readline()
    try:
        lineCount = int(lineCount.split()[0])
    except:
        return (1, '<span class="error">[ERROR] Failed to get a line count of: %s:%s (%s)</span>' % (appInfo['host'], file, lineCount))

    if start_line > lineCount:
        start_line = 1
    
    lines = []
    log_level = ''
    for line in f.readlines():
        if line.find('[DEBUG') >= 0:
            line = '<span class="debug">%s</span><br/>' % __escape(line.rstrip())
            log_level = 'DEBUG'
        elif line.find('[INFO') >= 0:
            line = '<span class="info">%s</span><br/>' % __escape(line.rstrip())
            log_level = 'INFO'
        elif line.find('[WARN') >= 0:
            line = '<span class="warn">%s</span><br/>' % __escape(line.rstrip())
            log_level = 'WARN'
        elif line.find('[ERROR') >= 0:
            line = '<span class="error">%s</span><br/>' % __escape(line.rstrip())
            log_level = 'ERROR'
        elif log_level == 'WARN' or log_level == 'ERROR':
            line = '<span class="%s">%s</span><br/>' % (log_level, __escape(line.rstrip()))
        else:
            line = '<span>%s</span><br/>' % __escape(line.rstrip())
        lines.append(line)
        start_line += 1

    if f.close():
        return (1, '<span class="error">[ERROR] Failed to read log file: %s:%s</span>' % (appInfo['host'], file))
    else:
        return (start_line, ''.join(lines))

def __escape(html):
    return html.replace('&', '&amp;').replace('<', '&lt;').replace('>', '&gt;').replace('"', '&quot;').replace("'", '&#39;')

def html_header(theApp, file):
    # generate links
    links = []
    for app in APPS_LIST:
        links.append('<a href="./?app=%s">%s</a>' % (app, APPS[app]['name']))

    # set title, header and download link
    title = APPS.get(theApp) and APPS[theApp]['name'] or 'View Log Files'
    header = APPS.get(theApp) and APPS[theApp]['host'] + ': ' + file or ''
    downloadLink = APPS.get(theApp) and '<a href="download_log?app=%s&file=%s" title="Download"><img src="/download.gif" alt="Download" border="none"/></a>' % (theApp, file) or ''

    return """
<html>
<head>
<title>%s</title>
<style>
body {
    font-family: verdana, arial, sans-serif;
}

#loglinks {
    float: left;
    width: 100%%;
    margin-bottom: 20px;
}

#loglinks a {
    font-size: 0.85em;
    white-space: nowrap;
}

#log { color: #0000ff; }
#log .debug { color: #000000; }
#log .info { color: #208920; }
#log .warn { color: #9c20ee; }
#log .error { color: #ac2020; }

#pause-img {
    position: absolute;
    top: -100px;
    left: 0;
    cursor: pointer;
    z-index: 1;
}

#play-img {
    position: absolute;
    top: -100px;
    left: 0;
    cursor: pointer;
    z-index: 0;
}
</style>
<script language="JavaScript">
function ajaxGet(url, callback) {
    httpGet(url, function(xmldom) {
        var resp = xmldom.firstChild;
        while (resp) {
            if (resp.nodeName == 'ajax-response') {
                break;
            }
            resp = resp.nextSibling;
        }

        var retVal = new Object();
        if (resp) {
            var attributes = resp.attributes;
            for (var i = 0; i < attributes.length; i++) {
                var attr = attributes.item(i);
                retVal[attr.name] = attr.value;
            }

            var child = resp.firstChild;
            while (child) {
                if (child.nodeName == '#cdata-section') {
                    retVal.data = child.data;
                    break;
                }
                child = child.nextSibling;
            }
        }
        callback(retVal);
    });
}

function httpGet(url, callback) {
    var http = getXMLHTTP();
    http.open("GET", url, true);
    http.onreadystatechange = function() {
        if (http.readyState == 4) {
            var xml = http.responseXML;
            if (xml && xml.firstChild) {
                callback(xml);
            }
            else {
                callback(http.responseText);
            }
        }
    };

    http.send(null);
}

function getXMLHTTP() {
    var xmlhttp;
    try {
	xmlhttp = new XMLHttpRequest();
    }
    catch (e) {
	try {
	    xmlhttp = new ActiveXObject("Microsoft.XMLHTTP");
	}
	catch (e) {
	    throw "Unable to create an HTTP Request object";
	}
    }
    return xmlhttp;
}

var tail = true;
function refreshLog() {
    var theApp = document.forms[0].theApp;
    var theFile = document.forms[0].theFile;
    var startLine = document.forms[0].startLine;
    if (! tail) {
        window.setTimeout(refreshLog, 5000);
        return;
    }

    ajaxGet('get_log?app=' + theApp.value + '&file=' + theFile.value + '&start_line=' + startLine.value,
        function(resp) {
            if (resp.data && resp.data.length > 0) {
                startLine.value = resp.startLine;
                var newLines = document.createElement('DIV');
                newLines.innerHTML = resp.data;
                document.getElementById('log').appendChild(newLines);
                if (document.body.scrollHeight > document.body.clientHeight)
                {
                    document.body.scrollTop = document.body.scrollHeight - document.body.clientHeight;
                }

                var pause = document.getElementById("pause-img");
                var play = document.getElementById("play-img");
                pause.style.top = (document.body.scrollHeight - 22) + 'px';
                pause.style.left = (document.body.clientWidth - 22) + 'px';
                play.style.top = (document.body.scrollHeight - 22) + 'px';
                play.style.left = (document.body.clientWidth - 22) + 'px';
            }
            window.setTimeout(refreshLog, 5000);
        }
    );
}

function stopRefresh() {
    var pause = document.getElementById("pause-img");
    pause.style.display = 'none';
    tail = false;
}

function resumeRefresh() {
    var pause = document.getElementById("pause-img");
    pause.style.display = '';
    tail = true;
}

function handleScroll() {
    var pause = document.getElementById("pause-img");
    var play = document.getElementById("play-img");
    var left = document.body.clientWidth + document.body.scrollLeft - 22;
    pause.style.left = left + 'px';
    play.style.left = left + 'px';
}

window.onscroll = handleScroll;
</script>
</head>

<body onload="refreshLog();">
<div id="loglinks">%s</div>
<h3 id="header">%s %s</h3>
<form>
<input type="hidden" name="theApp" value="%s"/>
<input type="hidden" name="theFile" value="%s"/>
<input type="hidden" name="startLine" value="1"/>
</form>
<div>
<pre id="log">""" % (title, '&nbsp;|&nbsp;'.join(links), header, downloadLink, theApp, file)

def html_footer():
    return """</pre></div>
<img id="pause-img" src="/pause.gif" title="Pause" onclick="stopRefresh();"/>
<img id="play-img" src="/play.gif" title="Continue" onclick="resumeRefresh();"/>
</body></html>"""