first working login logout day chart

mtsenliven.py

@@ -57,10 +57,10 @@ except:
           " minetest-server package or compiling from git instructions"
           " on minetest.net")
     exit(1)
-msg_flags = ["WARNING[Server]: ", "ACTION[Server]: "]
+msgprefix_flags = ["WARNING[Server]: ", "ACTION[Server]: "]
-msg_lists = {}  # where flag is key
+msgprefix_lists = {}  # where flag is key
-for flag in msg_flags:
+for flag in msgprefix_flags:
-    msg_lists[flag] = []
+    msgprefix_lists[flag] = []
 # see https://www.endpoint.com/blog/2015/01/28/getting-realtime-output-
 # using-python
 
@@ -91,7 +91,7 @@ def print_unique_only(output, err_flag=False):
         if flag in output:
             always_show_enable = True
     if not always_show_enable:
-        for flag in msg_flags:
+        for flag in msgprefix_flags:
         # such as '2018-02-06 21:08:06: WARNING[Server]: Deprecated call to get_look_yaw, use get_look_horizontal instead'
         # or 2018-02-06 21:08:05: ACTION[Server]: [playereffects] Wrote playereffects data into /home/owner/.minetest/worlds/FCAGameAWorld/playereffects.mt.
             f_i = output.find(flag)
@@ -105,10 +105,10 @@ def print_unique_only(output, err_flag=False):
                     sub_msg = wrap["opener"] + "..." + wrap["closer"]
                     msg_msg = "similar messages"
                     break
-            if sub_msg in msg_lists[found_flag]:
+            if sub_msg in msgprefix_lists[found_flag]:
                 show_enable = False
             else:
-                msg_lists[found_flag].append(sub_msg)
+                msgprefix_lists[found_flag].append(sub_msg)
     if show_enable:
         print(output_strip)
         if found_flag is not None:

webapp/README.md

@@ -10,6 +10,7 @@ see <https://stackoverflow.com/questions/18543047/mocha-monitor-application-outp
 ## Developer Notes
 
 ### Things webapp should deprecate
+* mtanalyze/web
 * /home/owner/GitHub/EnlivenMinetest/etc/change_hardcoded_world_name_first/eauth
   * shell script which contains only `nano ~/.minetest/worlds/FCAGameAWorld/auth.txt`
 * mts-ENLIVEN and mtsenliven.py (run minetestserver with selected game and world)

webapp/node_modules/n-readlines/.npmignore

@@ -0,0 +1,2 @@
+node_modules
+npm-debug.log

webapp/node_modules/n-readlines/.travis.yml

@@ -0,0 +1,6 @@
+language: node_js
+os:
+    - linux
+    - osx
+node_js:
+    - "0.10"

webapp/node_modules/n-readlines/LICENSE

@@ -0,0 +1,20 @@
+The MIT License (MIT)
+
+Copyright (c) 2013 Liucw
+
+Permission is hereby granted, free of charge, to any person obtaining a copy of
+this software and associated documentation files (the "Software"), to deal in
+the Software without restriction, including without limitation the rights to
+use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
+the Software, and to permit persons to whom the Software is furnished to do so,
+subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
+IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

webapp/node_modules/n-readlines/README.md

@@ -0,0 +1,48 @@
+[![Build Status](https://travis-ci.org/nacholibre/node-readlines.svg)](https://travis-ci.org/nacholibre/node-readlines)
+# node-readlines
+Reading file line by line may seem like a trivial problem, but in node, there is no straightforward way to do it. There are a lot of libraries using Transform Streams to achieve it, but it seems like a overkill, so I've wrote simple version using only the `filesystem` module of node. Note that this is *synchronous* library.
+
+Install with
+`npm install n-readlines`
+
+---------------------------------------
+
+## Documentation
+### new readlines(filename, [options]);
+### new readlines(fd, [options]);
+
+**Arguments**
+
+* `filename` - String path to the file you want to read from
+* `fd` - File descriptor
+* `options` - Object
+  * `readChunk` - Integer number of bytes to read at once. Default: 1024
+  * `newLineCharacter` - String new line character, only works with one byte characters for now. Default: `\n` which is `0x0a` hex encoded
+
+`node-readlines` can handle files without newLineCharacter after the last line
+
+---------------------------------------
+
+### readlines.next()
+Returns `buffer` with the line data without the `newLineCharacter` or `false` if end of file is reached.
+
+---------------------------------------
+### readlines.reset()
+Resets the pointer and starts from the beginning of the file. This works only if the end is not reached.
+
+---------------------------------------
+
+## Example
+```javascript
+var lineByLine = require('n-readlines');
+var liner = new lineByLine('./textFile.txt');
+
+var line;
+var lineNumber = 0;
+while (line = liner.next()) {
+    console.log('Line ' + lineNumber + ': ' + line.toString('ascii'));
+    lineNumber++;
+}
+
+console.log('end of line reached');
+```

webapp/node_modules/n-readlines/dummy_files/badEndFile.txt

@@ -0,0 +1,2 @@
+google.com
+yahoo.com

webapp/node_modules/n-readlines/dummy_files/noNewLinesFile.txt

@@ -0,0 +1 @@
+no new line

webapp/node_modules/n-readlines/dummy_files/normalFile.txt

@@ -0,0 +1,3 @@
+google.com
+yahoo.com
+yandex.ru

webapp/node_modules/n-readlines/dummy_files/twoLineFile.txt

@@ -0,0 +1,2 @@
+hello
+hello2

webapp/node_modules/n-readlines/dummy_files/withEmptyLines.txt

@@ -0,0 +1,5 @@
+hello
+hello4
+
+hello2
+hello3

webapp/node_modules/n-readlines/example.js

@@ -0,0 +1,13 @@
+'use strict';
+
+var lineByLine = require('./readlines.js');
+var liner = new lineByLine('./dummy_files/twoLineFile.txt');
+
+var line;
+var lineNumber = 0;
+while (line = liner.next()) {
+    console.log('Line ' + lineNumber + ': ' + line.toString('ascii'));
+    lineNumber++;
+}
+
+console.log('end of line reached');

webapp/node_modules/n-readlines/package.json

@@ -0,0 +1,67 @@
+{
+  "_from": "n-readlines",
+  "_id": "n-readlines@0.2.8",
+  "_inBundle": false,
+  "_integrity": "sha512-FRr6GU0vooiPAuHMBt/Pspm4htItJKCehs8Q2urdUuigXsdQzP8V03UaQedeCmiygqJwtuGhnidWHRHhUOAg9w==",
+  "_location": "/n-readlines",
+  "_phantomChildren": {},
+  "_requested": {
+    "type": "tag",
+    "registry": true,
+    "raw": "n-readlines",
+    "name": "n-readlines",
+    "escapedName": "n-readlines",
+    "rawSpec": "",
+    "saveSpec": null,
+    "fetchSpec": "latest"
+  },
+  "_requiredBy": [
+    "#USER",
+    "/"
+  ],
+  "_resolved": "https://registry.npmjs.org/n-readlines/-/n-readlines-0.2.8.tgz",
+  "_shasum": "6022f0b1a034a32dc0bfcc0e8ca9fbd6877d341a",
+  "_spec": "n-readlines",
+  "_where": "/home/owner/GitHub/EnlivenMinetest/webapp",
+  "author": {
+    "name": "Yoan Arnaudov",
+    "email": "jonidev@gmail.com"
+  },
+  "bugs": {
+    "url": "https://github.com/nacholibre/node-readlines/issues"
+  },
+  "bundleDependencies": false,
+  "dependencies": {},
+  "deprecated": false,
+  "description": "Read file line by line without buffering the whole file in memory.",
+  "devDependencies": {
+    "mocha": "^2.0.1"
+  },
+  "engines": {
+    "node": ">=0.10.0"
+  },
+  "homepage": "https://github.com/nacholibre/node-readlines#readme",
+  "keywords": [
+    "read",
+    "line",
+    "reader",
+    "linereader",
+    "readfile",
+    "linebyline",
+    "synchronous",
+    "sync",
+    "readline",
+    "readlines"
+  ],
+  "license": "MIT",
+  "main": "./readlines.js",
+  "name": "n-readlines",
+  "repository": {
+    "type": "git",
+    "url": "git+ssh://git@github.com/nacholibre/node-readlines.git"
+  },
+  "scripts": {
+    "test": "./node_modules/mocha/bin/mocha *_test.js"
+  },
+  "version": "0.2.8"
+}

webapp/node_modules/n-readlines/readlines.js

@@ -0,0 +1,160 @@
+'use strict';
+
+var fs = require('fs');
+
+function LineByLine(file, options) {
+    options = options || {};
+
+    if (!options.readChunk) {
+        options.readChunk = 1024;
+    }
+
+    if (!options.newLineCharacter) {
+        options.newLineCharacter = 0x0a; //linux line ending
+    } else {
+        options.newLineCharacter = options.newLineCharacter.charCodeAt(0);
+    }
+
+    if (typeof file === 'number') {
+        this.fd = file;
+    } else {
+        this.fd = fs.openSync(file, 'r');
+    }
+
+    this.options = options;
+
+    this.newLineCharacter = options.newLineCharacter;
+
+    this.reset();
+}
+
+LineByLine.prototype._searchInBuffer = function(buffer, hexNeedle) {
+    var found = -1;
+
+    for (var i = 0; i <= buffer.length; i++) {
+        var b_byte = buffer[i];
+        if (b_byte === hexNeedle) {
+            found = i;
+            break;
+        }
+    }
+
+    return found;
+};
+
+LineByLine.prototype.reset = function() {
+    this.bufferData = null;
+    this.bytesRead = 0;
+
+    this.bufferPosition = 0;
+    this.eofReached = false;
+
+    this.line = '';
+
+    this.linesCache = [];
+
+    this.lastBytePosition = null;
+
+    this.fdPosition = 0;
+};
+
+LineByLine.prototype._extractLines = function(buffer) {
+    var line;
+    var lines = [];
+    var bufferPosition = 0;
+
+    var lastNewLineBufferPosition = 0;
+    while (true) {
+        var bufferPositionValue = buffer[bufferPosition++];
+
+        if (bufferPositionValue === this.newLineCharacter) {
+            line = buffer.slice(lastNewLineBufferPosition, bufferPosition);
+            lines.push(line);
+            lastNewLineBufferPosition = bufferPosition;
+        } else if (!bufferPositionValue) {
+            break;
+        }
+    }
+
+    var leftovers = buffer.slice(lastNewLineBufferPosition, bufferPosition);
+    if (leftovers.length) {
+        lines.push(leftovers);
+    }
+
+    return lines;
+};
+
+LineByLine.prototype._readChunk = function(lineLeftovers) {
+    var totalBytesRead = 0;
+
+    var bytesRead;
+    var buffers = [];
+    do {
+        var readBuffer = new Buffer(this.options.readChunk);
+
+        bytesRead = fs.readSync(this.fd, readBuffer, 0, this.options.readChunk, this.fdPosition);
+        totalBytesRead = totalBytesRead + bytesRead;
+
+        this.fdPosition = this.fdPosition + bytesRead;
+
+        buffers.push(readBuffer);
+    } while (bytesRead && this._searchInBuffer(buffers[buffers.length-1], this.options.newLineCharacter) === -1);
+
+    var bufferData = Buffer.concat(buffers);
+
+    if (bytesRead < this.options.readChunk) {
+        this.eofReached = true;
+        bufferData = bufferData.slice(0, totalBytesRead);
+    }
+
+    if (bytesRead) {
+        this.linesCache = this._extractLines(bufferData);
+
+        if (lineLeftovers) {
+            this.linesCache[0] = Buffer.concat([lineLeftovers, this.linesCache[0]]);
+        }
+    }
+
+    return totalBytesRead;
+};
+
+LineByLine.prototype.next = function() {
+    var line = false;
+
+    if (this.eofReached && this.linesCache.length === 0) {
+        return line;
+    }
+
+    var bytesRead;
+
+    if (!this.linesCache.length) {
+        bytesRead = this._readChunk();
+    }
+
+    if (this.linesCache.length) {
+        line = this.linesCache.shift();
+
+        var lastLineCharacter = line[line.length-1];
+
+        if (lastLineCharacter !== 0x0a) {
+            bytesRead = this._readChunk(line);
+
+            if (bytesRead) {
+                line = this.linesCache.shift();
+            }
+        }
+    }
+
+    if (this.eofReached && this.linesCache.length === 0) {
+        fs.closeSync(this.fd);
+        this.fd = null;
+    }
+
+    if (line && line[line.length-1] === this.newLineCharacter) {
+        line = line.slice(0, line.length-1);
+    }
+
+    return line;
+};
+
+module.exports = LineByLine;

webapp/node_modules/n-readlines/readlines_test.js

@@ -0,0 +1,106 @@
+'use strict';
+
+var lineByLine = require('./readlines.js');
+
+var assert = require('assert');
+
+describe('Line by line', function() {
+    it('should get all lines', function () {
+        var filename = __dirname + '/dummy_files/twoLineFile.txt';
+
+        var liner = new lineByLine(filename);
+
+        assert(liner.next().toString('ascii') === 'hello');
+        assert(liner.next().toString('ascii') === 'hello2');
+        assert(liner.next() === false);
+        assert(liner.next() === false);
+        assert(liner.fd === null);
+    });
+
+    it('should get all lines even if the file doesnt end with new line', function () {
+        var filename = __dirname + '/dummy_files/badEndFile.txt';
+
+        var liner = new lineByLine(filename);
+
+        assert(liner.next().toString('ascii') === 'google.com');
+        assert(liner.next().toString('ascii') === 'yahoo.com');
+        assert(liner.next() === false);
+        assert(liner.fd === null);
+    });
+
+    it('should get all lines if there is no new lines', function () {
+        var filename = __dirname + '/dummy_files/noNewLinesFile.txt';
+
+        var liner = new lineByLine(filename);
+
+        assert(liner.next().toString('ascii') === 'no new line');
+        assert(liner.next() === false);
+        assert(liner.fd === null);
+    });
+
+    it('should handle empty files', function () {
+        var filename = __dirname + '/dummy_files/emptyFile.txt';
+
+        var liner = new lineByLine(filename);
+
+        assert(liner.next() === false);
+        assert(liner.fd === null);
+    });
+
+    it('should read right between two chunks', function () {
+        var filename = __dirname + '/dummy_files/normalFile.txt';
+        var liner = new lineByLine(filename, {'readChunk': 16});
+
+        assert(liner.next().toString('ascii') === 'google.com');
+        assert(liner.next().toString('ascii') === 'yahoo.com');
+        assert(liner.next().toString('ascii') === 'yandex.ru');
+        assert(liner.next() === false);
+        assert(liner.fd === null);
+    });
+
+    it('should read empty lines', function () {
+        var filename = __dirname + '/dummy_files/withEmptyLines.txt';
+        var liner = new lineByLine(filename);
+
+        assert(liner.next().toString('ascii') === 'hello');
+        assert(liner.next().toString('ascii') === 'hello4');
+        assert(liner.next().toString('ascii') === '');
+        assert(liner.next().toString('ascii') === 'hello2');
+        assert(liner.next().toString('ascii') === 'hello3');
+        assert(liner.next() === false);
+        assert(liner.fd === null);
+    });
+
+    it('should reset and start from the beggining', function() {
+        var filename = __dirname + '/dummy_files/normalFile.txt';
+        var liner = new lineByLine(filename, {'readChunk': 16});
+
+        assert(liner.next().toString('ascii') === 'google.com');
+        assert(liner.next().toString('ascii') === 'yahoo.com');
+
+        liner.reset()
+
+        assert(liner.next().toString('ascii') === 'google.com');
+        assert(liner.next().toString('ascii') === 'yahoo.com');
+        assert(liner.next().toString('ascii') === 'yandex.ru');
+        assert(liner.next() === false);
+        assert(liner.fd === null);
+    });
+
+    it('should read big lines', function() {
+        var filename = __dirname + '/dummy_files/bigLines.json';
+        var liner = new lineByLine(filename);
+
+        var parsedLine = JSON.parse(liner.next().toString('ascii'));
+        assert(parsedLine);
+
+        var parsedLine = JSON.parse(liner.next().toString('ascii'));
+        assert(parsedLine);
+
+        var parsedLine = JSON.parse(liner.next().toString('ascii'));
+        assert(parsedLine);
+
+        assert(liner.next() === false);
+        assert(liner.fd === null);
+    });
+});

webapp/package-lock.json

@@ -232,6 +232,11 @@
       "resolved": "https://registry.npmjs.org/ms/-/ms-2.0.0.tgz",
       "integrity": "sha1-VgiurfwAvmwpAd9fmGF4jeDVl8g="
     },
+    "n-readlines": {
+      "version": "0.2.8",
+      "resolved": "https://registry.npmjs.org/n-readlines/-/n-readlines-0.2.8.tgz",
+      "integrity": "sha512-FRr6GU0vooiPAuHMBt/Pspm4htItJKCehs8Q2urdUuigXsdQzP8V03UaQedeCmiygqJwtuGhnidWHRHhUOAg9w=="
+    },
     "negotiator": {
       "version": "0.6.1",
       "resolved": "https://registry.npmjs.org/negotiator/-/negotiator-0.6.1.tgz",

webapp/package.json

@@ -13,6 +13,7 @@
   "dependencies": {
     "body-parser": "^1.18.2",
     "cookie-parser": "^1.4.3",
-    "express": "^4.7.2"
+    "express": "^4.7.2",
+    "n-readlines": "^0.2.8"
   }
 }

webapp/server.js

@@ -1,25 +1,34 @@
 'use strict';
 
+var tz_offset = 240; //subtract this from server time to get local time; 4hrs is 240; 5hrs is 300
+//TODO: handle tz_offset not divisible by 60
+//var selected_date_s = null;
+//selected_date_s = "2018-05-08";
+
+
 var express = require('express'),
 //var exphbs  = require("express-handlebars");
 //	exphbs  = require('../../'); // "express-handlebars"
 	cookieParser = require('cookie-parser'),
 	bodyParser = require('body-parser'),
 	//session = require('express-session'),
-	fs = require('fs');
+	fs = require('fs'),
+	readlines = require('n-readlines');
 const os = require('os');
 var app = express();
 //app.engine('handlebars', exphbs({defaultLayout: 'main'}));
 //app.set('view engine', 'handlebars');
 var players = [];
+var player_indices = {};
 //see https://developer.mozilla.org/en-US/docs/Learn/Server-side/Express_Nodejs/Introduction
 var prev_line = null;
 
 //#region derived from mtsenliven.py
-var msg_flags = ["WARNING[Server]: ", "ACTION[Server]: "]
+var msgprefix_flags = ["WARNING[Server]: ", "ACTION[Server]: "]
-var msg_lists = {}  // where flag is key
+var msgprefix_lists = {}  // where flag is key
-for (flag in msg_flags) {
+var mf_len = msgprefix_flags.length;
-	msg_lists[flag] = [];
+for (var mf_i=0; mf_i<mf_len; mf_i++) {
+	msgprefix_lists[msgprefix_flags[mf_i]] = [];
 }
 
 var non_unique_wraps = [];
@@ -33,32 +42,98 @@ var unique_flags = [
 ];
 //#endregion derived from mtsenliven.py
 
-function process_logline(line) {
+function process_logline(line, line_number, selected_date_s) {
-	var player_name = "";
+	//TODO: use store_unique_log_data instead of this function
+	var player_name = null;
 	var verb = "";
-	index = -1;
+	var time_s = "";
-	
+	var date_s = "";
-	if (player_name != "") {
+	var player_ip = null;
+	const time_start_i = 11;
+	var uf_len = unique_flags.length;
+	mf_len = msgprefix_flags.length;
+	var verb_i = -1;
+	var verb_number = -1;
+	var msgprefix_i = -1;
+	var msgprefix_number = -1;
+	var msgprefix = null;
+	var index_msg = "";
+	for (var mf_i=0; mf_i<mf_len; mf_i++) {
+		msgprefix_i = line.indexOf(msgprefix_flags[mf_i]);
+		if (msgprefix_i > -1) {
+			msgprefix_number = mf_i;
+			msgprefix = msgprefix_flags[mf_i];
+			break;
+		}
+	}
+	var skip_date_enable = false;
+	for (var uf_i=0; uf_i<uf_len; uf_i++) {
+		verb_i = line.indexOf(unique_flags[uf_i]);
+		if (verb_i > -1) {
+			verb_number = uf_i;
+			verb = unique_flags[uf_i];
+			date_s = line.substring(0,10).trim();
+			if (selected_date_s==null || selected_date_s==date_s) {
+				//console.log("(verbose message in process_logline) using '" + date_s + "' since selected '"+selected_date_s+"'");
+				time_s = line.substring(time_start_i, time_start_i+8);
+				//console.log("using time "+time_s);
+				if (msgprefix!=null) {
+					player_name = line.substring(msgprefix_i+msgprefix.length, verb_i).trim();
+					var ip_flag = " [";
+					var ip_i = player_name.indexOf(ip_flag);
+					if (ip_i > -1) {
+						player_ip = player_name.substring(ip_i+ip_flag.length, player_name.length-1);
+						player_name = player_name.substring(0,ip_i);
+					}
+				}
+				else {
+					player_name = "&lt;missing msgprefix&rt;";
+				}
+			}
+			else {
+				skip_date_enable = true;
+				//console.log("WARNING in process_logline: skipping '" + date_s + "' since not '"+selected_date_s+"'");
+			}
+			break;
+		}
+	}
+	var index = -1;  // player index
+	if (player_name != null) {
+		if (player_name.length > 0) {
 			if (player_indices.hasOwnProperty(player_name)) {
 				index = player_indices[player_name];
+				index_msg = "cached ";
 			}
 			else {
-			index = player_count;
+				index = players.length;
+				//players.push({});
 				players[index] = {};
 				players[index].display_name = player_name;
-			player_count++;
+				player_indices[player_name] = index;
+				//console.log("created new index "+index);
+			}
+		}
+		else {
+			console.log("WARNING in process_logline: zero-length player name");
 		}
-		
+	}
+	if (index<0 && !skip_date_enable) {
+		//console.log("(verbose message in process_logline) "+index_msg+"index was '"+index+"' but date was good '" + date_s + "' for '"+line+"'");
 	}
 	if (verb == "leaves game") {
-		players[index].logout_time = "";
+		if (index > -1) {
+			players[index].logout_time = time_s;
+		}
 	}
 	else if (verb == "joins game") {
-		players[index].login_time = "";
+		if (index > -1) {
+			//console.log("using index " + index);
+			players[index].login_time = time_s;
+		}
 	}
 }
 
-function relog_unique_only(output, err_flag=false) {
+function store_unique_log_data(output, line_number, err_flag=false) {
 	var ret = "";
 	var output_strip = output.trim();
 	var u_prefix = "active block modifiers took ";
@@ -76,13 +151,13 @@ function relog_unique_only(output, err_flag=false) {
 		}
 	}
 	if (!always_show_enable) {
-		var mf_len = msg_flags.length;
+		var mf_len = msgprefix_flags.length;
 		for (var mf_i=0; mf_i<mf_len; mf_i++) {
 			// such as '2018-02-06 21:08:06: WARNING[Server]: Deprecated call to get_look_yaw, use get_look_horizontal instead'
 			// or 2018-02-06 21:08:05: ACTION[Server]: [playereffects] Wrote playereffects data into /home/owner/.minetest/worlds/FCAGameAWorld/playereffects.mt.
-			f_i = output.find(msg_flags[mf_i]);
+			f_i = output.find(msgprefix_flags[mf_i]);
 			if (f_i >= 0) {
-				found_flag = msg_flags[mf_i];
+				found_flag = msgprefix_flags[mf_i];
 				break;
 			}
 		}
@@ -98,11 +173,11 @@ function relog_unique_only(output, err_flag=false) {
 					break;
 				}
 			}
-			if (msg_lists[found_flag].indexOf(sub_msg) > -1) {
+			if (msgprefix_lists[found_flag].indexOf(sub_msg) > -1) {
 				show_enable = false;
 			}
 			else {
-				msg_lists[found_flag].push(sub_msg);
+				msgprefix_lists[found_flag].push(sub_msg);
 			}
 		}
 	}
@@ -114,9 +189,10 @@ function relog_unique_only(output, err_flag=false) {
 	}
 	return ret;
 }
-
+var cached_date = null;
 app.get('/', function (req, res) {
 	var ret = "";
+	ret += '<html><body style="font-family:calibri,sans">';
 	// Whenever server starts the following is logged
 	// (see also etc/example-input.txt):
 	//
@@ -124,11 +200,47 @@ app.get('/', function (req, res) {
 	//  Separator
 	//-------------
 	//
-	ret += os.homedir();
+	var selected_date_s = null;
+	if (req.query.date) selected_date_s = req.query.date
+	ret += "assuming minetestserver ran as: " + os.homedir() + "<br/>\n";
+	ret += "timezone (tz_offset/60*-1): " + (Math.floor(tz_offset/60)*-1) + "<br/>\n";
+	ret += "date (this YYYY-MM-DD filter limits all log processing): " + selected_date_s + "<br/>\n";
+	if (selected_date_s==null) {
+		ret += '<a href="?date=2018-05-08">2018-05-08</a>';
+	}
+	if (cached_date!=selected_date_s && selected_date_s!=null) {
+		cached_date = selected_date_s;
+		players = [];
+		player_indices = [];
+		var log_paths = [os.homedir() + "/.minetest/debug_archived/2018/05/08.txt", os.homedir() + "/.minetest/debug.txt"];
+		var lp_len = log_paths.length;
+		for (var lp_i=0; lp_i<lp_len; lp_i++) {
+			var this_log_path = log_paths[lp_i];
+			console.log("EnlivenMinetest webapp reading '" + this_log_path + "'...");
+			var line_number = 1;
+			if (fs.existsSync(this_log_path)) {
+				//uses n-readlines package: see https://stackoverflow.com/questions/34223065/read-lines-synchronously-from-file-in-node-js
+				var liner = new readlines(this_log_path);
+				var next = true;
+				while (next) {
+					next = liner.next();
+					if (next!=false) {
+						process_logline(next.toString('ascii'), line_number, selected_date_s);
+						line_number++;
+					}
+				}
+			}
+			else {
+				console.log("WARNING: file not found: '" + this_log_path + "' (listing actual archived log folders is not yet implemented, so this is a hard-coded demo folder only on poikilos' server)");
+			}
+		}
+
+	}
+
 	//see ~/.minetest/debug.txt
 	//and logs archived by EnlivenMinetest:
 	//~/.minetest/debug_archived/2018/05/08.txt
-	var ret += `<canvas id="myCanvas" width="100" height="1540"> <!--style="border:1px solid #c3c3c3;">-->
+	ret += `<canvas id="myCanvas" width="100" height="1540"> <!--style="border:1px solid #c3c3c3;">-->
 Your browser does not support the canvas element.
 </canvas>
 <div style="color:gray" id="outputArea">loading...</div>
@@ -161,12 +273,6 @@ outputE.innerHTML = stats_html;`;
 
 
 	var arrayLength = players.length;
-	player_count = 0;
-	player_indices = {};
-	var index = -1;
-	for () {
-		process_logline(line);
-	}
 	for (var i = 0; i < arrayLength; i++) {
 		ret += 'players[' + i + '] = {};' + "\n";
 		ret += 'players[' + i + '].login_time = "' + players[i].login_time + '";' + "\n";
@@ -179,8 +285,9 @@ var ctx = canvas.getContext("2d");
 ctx.font = text_size+"px Arial";
 var arrayLength = players.length;
 var text_x;
-var index = -1;
+var index = -1;`
-for (var i = 0; index < arrayLength; i++) {
+	ret += 'var tz_offset = ' + tz_offset + ';';
+	ret += `for (var i = 0; index < arrayLength; i++) {
 	text_x = text_start_x;
 	ctx.fillStyle = "#dce5ea";
 	ctx.fillRect(0, border_y+1.0, player_name_width, row_y_offset-1.0);
@@ -213,7 +320,13 @@ for (var i = 0; index < arrayLength; i++) {
 		ctx.fillText(players[index].display_name, text_x, text_y);
 		var border_x = border_start_x;
 		var login_places = players[index].login_time.split(':');
+		if (login_places.length>=3) {
+			login_places[0] -= Math.floor(tz_offset/60);
+		}
 		var logout_places = players[index].logout_time.split(':');
+		if (logout_places.length>=3) {
+			logout_places[0] -= Math.floor(tz_offset/60);
+		}
 		var login_second = (+login_places[0]) * 60 * 60 + (+login_places[1]) * 60 + (+login_places[2]);
 		var login_m = login_second / 60.0;
 		var logout_second = (+logout_places[0]) * 60 * 60 + (+logout_places[1]) * 60 + (+logout_places[2]);
@@ -236,16 +349,16 @@ for (var i = 0; index < arrayLength; i++) {
 	index++;
 }
 </script>`;
+	ret += '</body></html>';
 	res.send(ret);
 	//res.render('home');
 });
 
+
+
 var server = app.listen(3000, function () {
 	//console.log('express-handlebars example server listening on: 3000');
 	var host = server.address().address;
 	var port = server.address().port;
-	var this_log_path = os.homedir() + "/.minetest/debug_archived/2018/05/08.txt";
-	console.log("EnlivenMinetest webapp reading '" + this_log_path + "'...");
-	
 	console.log("EnlivenMinetest webapp listening at http://%s:%s", host, port);
 });