Showing posts with label software development. Show all posts
Showing posts with label software development. Show all posts

Header Text Resizing on Scroll

This is a useful tool for any modern website UI with content that you want to showcase (and get the header content out of the way as much as you can).

CodePen: https://codepen.io/radagast27/pen/JqWENL

Source: This feature works by having JavaScript detect when a certain scroll position from the top of the web document (50 in this case) has been reached at which point a resize animation of the header text and area takes place. Then, the reverse happens when that same scroll position is reached while scrolling back up.

 <!DOCTYPE html>  
 <html>  
 <head>  
 <meta name="viewport" content="width=device-width, initial-scale=1">  
 <style>  
 body {   
  margin: 0;  
  font-family: Arial, Helvetica, sans-serif;  
  color: white;  
  background-color: black;  
 }  
 #header {  
  background-color: green;  
  padding: 30px 30px;  
  color: lightblue;  
  text-align: left;  
  font-size: 74px;   
  font-weight: bold;  
  position: fixed;  
  top: 0;  
  margin-bottom:5%;  
  width: 100%;  
  transition: 0.4s;  
 }  
 </style>  
 </head>  
 <body>  
 <div id="header">Hello.</div>  
 <div style="margin-top:190px; padding:15px 15px 250px 15px;">  
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      tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat. Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur. Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim id est laborum.Lorem ipsum dolor dummy text sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat. Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur. Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim id est laborum. ipsum dolor dummy text sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat. Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur. Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim id est laborum.Lorem ipsum dolor dummy text sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat. Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur. Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim id est laborum. ipsum dolor dummy text sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat. Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur. Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim id est laborum.Lorem ipsum dolor dummy text sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat. Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur. Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim id est laborum. ipsum dolor dummy text sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat. Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur. Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim id est laborum.Lorem ipsum dolor dummy text sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat. Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur. Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim id est laborum. ipsum dolor dummy text sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat. Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur. Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim id est laborum.Lorem ipsum dolor dummy text sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat. Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur. Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim id est laborum. ipsum dolor dummy text sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat. Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur. Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim id est laborum.Lorem ipsum dolor dummy text sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat. Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur. Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim id est laborum. ipsum dolor dummy text sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat. Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur. Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim id est laborum.Lorem ipsum dolor dummy text sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat. Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur. Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim id est laborum. ipsum dolor dummy text sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat. Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur. Excepteur sint occaecat consequat. Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur. Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim id est laborum. ipsum dolor dummy text sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat. Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur. Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim id est laborum.Lorem ipsum dolor dummy text sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat. Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur. Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim id est laborum. ipsum dolor dummy text sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat. Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur. Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim id est laborum.Lorem ipsum dolor dummy text sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat. Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur. Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim id est laborum. ipsum dolor dummy text sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat. Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur. Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim id est laborum.  
  </p>  
  <br />  
  The end.  
 </div>  
 <script>  
 window.onscroll = function() {scrollFunction()};  
 function scrollFunction() {  
  var hdr = document.getElementById("header")  
  if (document.body.scrollTop > 50 || document.documentElement.scrollTop > 50) {  
   hdr.style.fontSize = "30px";  
   hdr.style.height = "2%";  
  } else {  
   hdr.style.fontSize = "74px";  
   hdr.style.height = "10%";  
  }  
 }  
 </script>  
 </body>  
 </html>


Reference: https://www.w3schools.com/howto/tryit.asp?filename=tryhow_js_shrink_header_scroll
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Regular Expressions

Regular expressions are a strings of (regex) code and matching (character) references used for finding patterns of characters within some defined contiguous string of characters (ie. forms validation, an IDE identifying opening and closing tags in markup code or a terminating semicolon in Java/C#). A more official definition describes regex as:
"In computing, regular expressions provide a concise and flexible means for identifying strings of text of interest, such as particular characters, words, or patterns of characters. Regular expressions (abbreviated as regex or regexp, with plural forms regexes, regexps, or regexen) are written in a formal language that can be interpreted by a regular expression processor, a program that either serves as a parser generator or examines text and identifies parts that match the provided specification."

 This diagram breaks down the gist of how an expression works- see the reference below for full list of matching modifiers and syntax

Having more than a passing familiarity with regex can be a tremendous help when doing any kind of development related to the identification of patterns in character/symbol data. When you understand how each component works you can very easily begin to build your own expressions to suit your particular application's pattern matching needs.

Below are some common regular expressions:

Alphanumeric Strings and Chars
^\w+$

Username (16 characters)
/^[a-z0-9_-]{3,16}$/

Hexadecimal ID
/^#?([a-f0-9]{6}|[a-f0-9]{3})$/

Email
/^([a-z0-9_\.-]+)@([\da-z\.-]+)\.([a-z\.]{2,6})$/

URL
/^(https?:\/\/)?([\da-z\.-]+)\.([a-z\.]{2,6})([\/\w \.-]*)*\/?$/

ipV4 Address
/^(?:(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\.){3}(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)$/

HTML Tag
/^<([a-z]+)([^<]+)*(?:>(.*)<\/\1>|\s+\/>)$/

XML Tags
Don't use Regex, use something like XPath


Just remember that the brackets are regex matching patterns, the curly braces are index positioners, the parens surround regex "capture groups" and the other syntax denotes flags for how much to match and other special conditions to be applied to the match/regex expression. Go here to practice and learn more: https://regexr.com/
The above illustrates Regex in 2 Capture Groups, One for alpha chars and the other for numeric chars


 Reference: https://code.tutsplus.com/tutorials/8-regular-expressions-you-should-know--net-6149
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Continuous Integration

"Continuous Integration (CI) is a development practice that requires developers to integrate code into a shared repository several times a day. Each check-in is then verified by an automated build, allowing teams to detect problems early."


The idea behind CI is that by having all developers continuously tracking (pulling down changes from)- and incrementally integrating their branch/feature code into- a "master" branch (or some common branch that facilitates CI of all other branches), problems that stem from incompatible or "not easily merge-able" features surface at the first detection of incompatibility, as opposed to at the end of feature branch development when any incompatibilities are magnified, and result in time-consuming redesign efforts to make things merge and interoperate cleanly.

In short, CI is used to nip potential integration problems in the bud.
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Accessing SQL Server Data in Python

So you want to access Microsoft SQL Server from your Python script(s)?

After weeding out some long-abandoned and/or nonworking solutions, I discovered a very simple Python ODBC driver that works with virtually all SQL Servers since MSSQL 2005 called "pyodbc". 

First, you will need to install this MSSQL ODBC (13.1 or 17 should work) component on your machine in addition to installing the pyodbc driver.

Next, get the pyodbc module for Python by running this from Windows command prompt:

pip install pyodbc

Then open up a python shell using 'py' or 'python' and enter the following after editing configuration values to match your development environment:

 import pyodbc  
 cnxn = pyodbc.connect('DRIVER={ODBC Driver 17 for SQL Server};SERVER=localhost;DATABASE=WideWorldImporters;UID=DemoUser;PWD=123Password')  
 cursor = cnxn.cursor()  
 #Sample of a simple SELECT  
 cursor.execute("SELECT TOP (100) Comments, count(*) FROM WideWorldImporters.Sales.Orders GROUP BY Comments")  
 row = cursor.fetchone()   
 while row:   
   print(row[0] + ': ' + str(row[1]))  
   row = cursor.fetchone()

Running this code will result in the below if you have configured everything correctly (note this example makes use of the Microsoft SQL Server demo WorldWideImporters database):


Reference: https://docs.microsoft.com/en-us/sql/connect/python/pyodbc/step-3-proof-of-concept-connecting-to-sql-using-pyodbc?view=sql-server-2017
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Refactoring Made Obvious

Refactoring (as a term if not as a practice) gets thrown around quite a bit. Sometimes really necessary refactoring doesn't get the priority it deserves because it is hard to quantify or even visualize/sense the result of a good refactoring (it should be relatively transparent in experience to the original, any differences should be optimization or enhancement- without losing of the original functionality along the way). We can take the case of a simple JavaScript animation, for example.

Simple animating of "+" dropping across the browser screen

Long ago, I used a mobile app that had a neat UI animation feature I really liked, but it took me a while to track down just how to accomplish it. I found some good starting points on SO, and began implementing a draft on JSFiddle.net.

The animation behavior I went about creating is simply a delay of an HTML element falling from the screen (via the "topToBottom" variable you'll see below- which is just the browser screen height property) . In a cascading and sequential set of delays, each falling element is pushed an increasing distance from the left of the screen so that the elements can fall independently (otherwise you would see just one column for all of the falling +'s in the end result).

In the following 4 steps, I am going to present a very basic refactoring scenario- going from the code template references I found, to the final refactored code (css, html and .js).

(1) First I found a fiddle via the SO question reference below: http://jsfiddle.net/reWwx/4/

(2) I then changed the code to create my own draft on JSFiddle.net: http://jsfiddle.net/reWwx/539/

(3) Next, I created an .htm file with the CSS styles and JavaScript inline (not quite what we'd want to check into source control...):
 <html>  
 <head>  
 <style>  
 body {height: 600px; background-color: #999}  
 #line-3 {  
   position:absolute;  
   width:100%;  
   left:20px;  
   top:0px;  
 }  
 #line-4 {  
   position:absolute;  
   width:100%;  
   left:30px;  
   top:0px;  
 }  
 #line-5 {  
   position:absolute;  
   width:100%;  
   left:40px;  
   top:0px;  
 }  
 #line-6 {  
   position:absolute;  
   width:100%;  
   left:55px;  
   top:0px;  
 }  
 #line-7 {  
   position:absolute;  
   width:100%;  
   left:70px;  
   top:0px;  
 }  
 #line-8 {  
   position:absolute;  
   width:100%;  
   left:85px;  
   top:0px;  
 }  
 #line-9 {  
   position:absolute;  
   width:100%;  
   left:100px;  
   top:0px;  
 }  
 #line-10 {  
   position:absolute;  
   width:100%;  
   left:115px;  
   top:0px;  
 }  
 #line-11 {  
   position:absolute;  
   width:100%;  
   left:130px;  
   top:0px;  
 }  
 #line-12 {  
   position:absolute;  
   width:100%;  
   left:145px;  
   top:0px;  
 }  
 #line-13 {  
   position:absolute;  
   width:100%;  
   left:160px;  
   top:0px;  
 }  
 #line-14 {  
   position:absolute;  
   width:100%;  
   left:175px;  
   top:0px;  
 }  
 #line-15 {  
   position:absolute;  
   width:100%;  
   left:195px;  
   top:0px;  
 }  
 #line-16 {  
   position:absolute;  
   width:100%;  
   left:210px;  
   top:0px;  
 }  
 </style>  
 <script>  
 $(document).ready(function(){  
   var bodyHeight = $('body').height();  
   var footerOffsetTop = $('#line-3').offset().top;  
   var topToBottom = bodyHeight -footerOffsetTop;  
  $('#line-3').css({top:'auto',bottom:topToBottom});  
  $("#line-3").delay(100).animate({  
   bottom: '100px',  
   }, 2200);   
  $('#line-4').css({top:'auto',bottom:topToBottom});  
  $("#line-4").delay(108).animate({  
   bottom: '100px',  
   }, 2200);   
  $('#line-5').css({top:'auto',bottom:topToBottom});  
  $("#line-5").delay(145).animate({  
   bottom: '100px',  
   }, 2200);   
  $('#line-6').css({top:'auto',bottom:topToBottom});  
  $("#line-6").delay(119).animate({  
   bottom: '100px',  
   }, 2200);   
  $('#line-7').css({top:'auto',bottom:topToBottom});  
  $("#line-7").delay(115).animate({  
   bottom: '100px',  
   }, 2200);   
    $('#line-8').css({top:'auto',bottom:topToBottom});  
  $("#line-8").delay(176).animate({  
   bottom: '100px',  
   }, 2100);   
    $('#line-9').css({top:'auto',bottom:topToBottom});  
  $("#line-9").delay(13).animate({  
   bottom: '100px',  
   }, 2200);   
    $('#line-10').css({top:'auto',bottom:topToBottom});  
  $("#line-10").delay(12).animate({  
   bottom: '100px',  
   }, 2200);   
    $('#line-11').css({top:'auto',bottom:topToBottom});  
  $("#line-11").delay(11).animate({  
   bottom: '100px',  
   }, 2000);   
    $('#line-12').css({top:'auto',bottom:topToBottom});  
  $("#line-12").delay(10).animate({  
   bottom: '100px',  
   }, 2100);   
    $('#line-13').css({top:'auto',bottom:topToBottom});  
  $("#line-13").delay(11).animate({  
   bottom: '100px',  
   }, 600);   
    $('#line-14').css({top:'auto',bottom:topToBottom});  
  $("#line-14").delay(14).animate({  
   bottom: '100px',  
   }, 700);   
      $('#line-15').css({top:'auto',bottom:topToBottom});  
  $("#line-15").delay(14).animate({  
   bottom: '100px',  
   }, 800);   
      $('#line-16').css({top:'auto',bottom:topToBottom});  
  $("#line-16").delay(24).animate({  
   bottom: '100px',  
   }, 900);   
 })  
 </script>  
 </head>  
 <body>  
 <div id="line-3">+</div>  
 <div id="line-4">+</div>  
 <div id="line-5">+</div>  
 <div id="line-6">+</div>  
 <div id="line-7">+</div>  
 <div id="line-8">+</div>  
 <div id="line-9">+</div>  
 <div id="line-10">+</div>  
 <div id="line-11">+</div>  
 <div id="line-12">+</div>  
 <div id="line-13">+</div>  
 <div id="line-14">+</div>  
 <div id="line-15">+</div>  
 <div id="line-16">+</div>  
 </body>    
 </html>
(4) And lastly I identified all of the repeating parts and made them dynamic in JavaScript, using the jQuery library to shorten much of the .js behavior:
  <html>   
  <head>   
  <style>   
  body {height: 600px; background-color: #000000; color:lime;}   
  div {   
   position:absolute;   
   top:0px;   
    width:100%;   
  }   
  </style>   
  <script src="https://ajax.googleapis.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>   
  <script>   
  $(document).ready(function(){   
   var base = $('#base');  
   var topToBottom = $('body').height();    
   for(i=0; i<83; i++){   
    base.append('<div id=\"line-'+i+'\" style=\"left:'+ Math.abs(i*10) +'\px">+</div>')   
    $("#line-" + i).css({top:'auto', bottom:topToBottom}).delay(100*i).animate({bottom: '100px'}, (1000));    
   }   
  })   
  </script>   
  </head>   
  <body id="base">   
  </body>    
  </html>

The final result contains the same behavior of the draft but it eliminates repetition by dynamically generating the HTML and dynamically attaching the falling action (which is really just coordinated position and visibility property changes behind the scenes of .animate()). Eliminating duplication, standardizing for better readability, reorganization for better clarity of code purpose and finding patterns (or finding different patterns that are a better match for the task) are the key concepts in refactoring.

Try it yourself by copying the code above, saving to an .htm file and opening the file in a web browser.

Final JSFiddle result: https://jsfiddle.net/radagast/6uzypc80/5

Larger font is always fun: https://twickrtape.azurewebsites.net/Home/About

Reference: https://stackoverflow.com/questions/8518400/jquery-animate-from-css-top-to-bottom
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DNS Rebinding and the Fallacy of "Walled Gardens"

Attacking Private Networks from the Internet with DNS Rebinding

The well-written research article above by Brannon Dorsey is a must-read for any developer of home-integrated devices, and perhaps, all developers, even those who develop products that run within highly secure networks that, via an authenticated user- (as was done with Stuxnet)- can inadvertently intercept and execute malicious code.

Don't let script kiddies mess with your code via DNS

Essentially Mr. Dorsey discovered that smart home gadgets that are supposed to operate securely in private networks can be exploited from the outside by simply embedding scripts containing network hi-jack exploits in links that can make requests back to the client browser that appear- via dynamic IP-to-same-origin-hostname switching* (ie. "DNS Spoofing") done through a malicious DNS server -to be from a trusted, same-origin source.

ie.

Malicious hostname: exploit.net
Malicious ip address: 59.33.12.9

Victim recent request hostname: somebank.com
Victim recent request ip address: 122.76.21.19

<<Very brief DNS Hijack via a malicious DNS server>>

Malicious hostname: exploit.net
Malicious ip address as far as victim browser client is aware: 122.76.21.19

......See the problem?

He goes on to explain how entire protocols like UPnP "are built around the idea that devices on the same network can trust each other".

Remember: what appears to the browser client to be a "same-origin" request is not always actually a same-origin request. Make sure that you change the default credentials on your network router(s) and as the article above insists:

"We need developers to write software that treats local private networks as if they were hostile public networks. The idea that the local network is a safe haven is a fallacy. If we continue to believe it people are going to get hurt."

Good to remember: protocol://host:port/path?query

*DNS cache poisoning, also known as DNS spoofing, is a type of attack that exploits vulnerabilities in the domain name system (DNS) to divert Internet traffic away from legitimate servers and towards fake ones.
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Visualize Hashing and Salt as Part of Password Encryption Process

The image below is a simplified and easy-to-understand illustration of how hashing and salting work. The main takeaway from this post- multiple users can have the same password, but will all have different salt values, thus making their hash result value different, and when you authenticate, you authenticate by the hash result value of your passwords, which is virtually always going to be unique for each user record:

Simple, no?

Even in the case of 2 users having the same hash result, the usernames will/should not be the same, so you still have distinct accounts, because UserID is also checked in the authentication process.

Companies increasingly (and for good data privacy reasons) do not even store the clear text textbox value you enter when you sign up for and then log into Fb, Google, Amazon, etc- they check your entered password's hash result against the hash result they have for your user/account record either from when you registered or last changed your password.

Good answer to the question you may come across, "what is the difference between salt and an IV (initialization vector)?" (TL;DR: not all IV's are salt, but salt is a kind of IV): https://security.stackexchange.com/questions/6058/is-real-salt-the-same-as-initialization-vectors

Reference: https://www.slideshare.net/rahulrajatsingh/password-hashing-28725754

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The GOF Software Design Patterns at a Glance

If you are serious about developing software, read this book. It contains timeless concepts you should know well.

 I. Creational Patterns
1. Abstract Factory - facilitates the creation of similar objects that share interface
2. Builder - dynamic SQL statements and other dynamically constructed code
3. Factory Method - custom way to construct an object (vs. normal/default class constructor)
4. Prototype - create new instances by copying existing instances
5. Singleton - assurance of 1 and only 1 instance of an entity in an application

II. Structural Patterns
1. Adapter - a means of making an object compatible with another object via a common interface
2. Bridge - the decoupling of the adaptor/interface and the incompatible items (light switch w/fans)
3. Composite - a group of objects treated the same way as a single instance of the same type of object
4. Decorator - adding new functionality to a class via subclass with new methods, props, etc.
5. Façade - simplified interface to a complicated backend
6. Flyweight - reuse of an object instance to create more instances of the same type
7. Proxy - entity serving as a stand-in for the real thing. Often a wrapper for a more complex class.

III. Behavioral Patterns
1. Chain of Responsibility - source command is served by multiple processes with distinct linear roles.
2. Command - encapsulate a request as an object, works great with HttpRequest and user actions
3. Interpreter - dynamic culture and localization settings to display appropriate UI text
4. Iterator - centralize communication among objects that have a common interface (ie. TV remote)
5. Mediator - centralize complex communication and control among related objects
6. Memento - persist and recall object state
7. Observer - a central watcher picks up picks up broadcast messages from everywhere it observes (Twitter)
8. State - persists object state and can react in different ways according to attributes of its current state
9. Strategy - enabling an object to change/choose algorithm(s) at runtime
10. Template Method - great for interfaces; design skeleton w/base needs; allow concretes to implement details
11. Visitor - code execution varies according to visiting object (ie. keyboard keys, mice clicks, WiFi Routers, etc.)
References:

https://softwareengineering.stackexchange.com/questions/234942/differentiating-between-factory-method-and-abstract-factory

https://www.cs.cmu.edu/~charlie/courses/15-214/2016-spring/slides/24%20-%20All%20the%20GoF%20Patterns.pdf

https://quizlet.com/129434321/design-patterns-gof-in-1-sentence-flash-cards/

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SOLID

"These principles, when combined together, make it easy for a programmer to develop software that are easy to maintain and extend." -Robert 'Uncle Bob' Martin

S - Single-Responsibility - objects should only serve one purpose

 O - Open-Closed - types should be open to extending capabilities, closed to base changes

 L - Liskov Substitution - subtypes of base types should produce objects compatible with base

 I - Interface Segregation - client types do not have to depend on unused interface methods

 D - Dependency Inversion - rely on abstract templates, not prescriptive/restrictive concretes
Reference: https://scotch.io/bar-talk/s-o-l-i-d-the-first-five-principles-of-object-oriented-design
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Levity on the Never-ending Race Towards the Next Big IT Trend

Because, c'mon now- at some level, every one of us can relate to 1 or both of these guys 😆

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Dynamic SQL

"a programming technique that enables you to build SQL statements dynamically at runtime." -Oracle Docs

Dynamic SQL is a very useful tool but should only be used when absolutely necessary. Having SQL compiled at runtime amplifies the threat of SQL injection and the readability of the SQL code (dynamic SQL SPs result in large double and quadruple quoted red text which can make things much more difficult to read than when reading regular highlighted SQL code).

But when circumstances require you to use dynamic SQL to get the data you need (ie. there is no other way to structure your database environment and/or the "dynamism" can't be done equally as easy or easier using some sort of data adapter like .NET CLR code) dynamic SQL may be your best option.

For more in-depth info on this subject, see this great reference from SQL Server MVP Erland Sommarskog on this subject and the pros and cons of using dynamic SQL: http://www.sommarskog.se/dynamic_sql.html

Here is a brief example of dynamic SQL:

 DECLARE @mult bit = 0  
 DECLARE @sqlToExecute varchar(500)  
 DECLARE @srvWest varchar(50) = 'WestZoneSqlSrv08'  
 DECLARE @srvEast varchar(50) = 'EastZoneSqlSrv08'  
 IF @mult = 0  
      SET @sqlToExecute = 'SELECT TOP 1 OrderId, PersonId FROM ALGO.dbo.[Order]'  
 ELSE  
      SET @sqlToExecute = 'SELECT TOP 1 OrderId, PersonId FROM ' + @srvEast + '.ALGO.dbo.[Order] UNION ALL SELECT TOP 1 OrderID, PersonId FROM ' + @srvWest + '.ALGO.dbo.Order'   
 EXEC(@sqlToExecute)
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Git Flow

Git or "directed acyclic graph" branch-based development is the maintaining of source code version history not just by file alone, but by a cryptographically unique snapshot of every file in your currently selected "working branch" at a point in time (commit).

This style of team development allows for the development of features that are isolated for easy plug-in/roll-back and integration of snapshots (commits) via merging of branches.

Developers need to beware of stepping on each other's toes (or working on the same files) as this can lead to merge conflicts.


For small business, corporate enterprise and all manner of sprawling code bases, Git is the best tool currently (March 2018) available to help manage the continuous change going on within your application source code.

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C# switch case, for/foreach loops and enum

Often in the earlier years of my software development career (esp. after working solely on SQL code for a long stretch of time), I would forget the exact syntax of some commonly used C# logic routines.

I've long since memorized the exact syntax for all of these, but I'd like to help someone else out there who may need a reminder in the future.

So here is a one-stop handy reference for these 3 commonly used C# constructs:

using System;
// enum
public enum Color { Red, Green, Blue }

public class Example
{   // switch
   public static void Main()
   {
      Color c = (Color) (new Random()).Next(0, 3);
      switch (c)
      {
         case Color.Red:
            Console.WriteLine("The color is red");
            break;
         case Color.Green:
            Console.WriteLine("The color is green");
            break;
         case Color.Blue:
            Console.WriteLine("The color is blue");   
            break;
         default:
            Console.WriteLine("The color is unknown.");
            break;   
      }
   }
}

// for loop
for (int i = 1; i <= 5; i++)
{
 Console.WriteLine(i);
}

 // foreach loop
int[] fibarray = new int[] { 0, 1, 1, 2, 3, 5, 8, 13 };
foreach (int element in fibarray)
{
    System.Console.WriteLine(element);
}
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Visual Studio Config Transforms

When you are working on software that needs to target different resources for different environments (ie. local, DEV, STAGE, PRODUCTION), you can easily manage your VS project environment through the use of .config transformation files.

Here is your default web.config:



Simply make an alternate version (with the same name) of the element you wish to change in your various configuration transformations (web.DEBUG.config, web.Development.config, etc.). In this example, we are setting up a transform to change the connection string that has the name, "applicationConnStr":



NOTE: The same configuration element (the same name, specifically) you want to transform must be in the base web.config file.

By default, the transformation we have set up will only be applied when the project is published. In order to get the transformations working with each build, you must edit the bottom of the *.csproj file with the following Target:

  <Target Name="BeforeBuild">
    <TransformXml 
        Source="Web.Base.config" 
        Transform="Web.$(Configuration).config" 
        Destination="Web.config" />
  </Target>



And be sure to uncomment the code, it is commented out by default. Now select a different build configuration, build your project, and you should see the "applicationConnStr" transformed to match the element from the web.config.[Debug||Release||etc.] that you selected to Build:




To add new web.config transform files, just right click on the web.config file and select "Add Config Transformation".



To associate your transformations with different builds, under the Build Dropdown, select "Configuration Manager..." and configure as you like:




Setting up build configurations that point to different web.configs (actually web.config "transforms") allows you to debug and run code according to your needs (ie. show DEMO at a meeting, Debug Development to uncover a bug, point to local for ongoing development, etc.).

ASP.NET Core has a very different configuration setup that uses JSON objects and more configurable things in .NET Core Startup.cs; this reference is for .NET Standard.

The key in all of this is the name of the element you are matching and then replacing. It just has to match in both places and all will be transformed on your application's web.config. In this example, we matched and replaced the value for a config element with the name, "applicationConnStr".

In a real-world scenario, there are many things that we could dynamically replace through config transforms: database connection strings, image servers, mail servers, file shares, printer locations, encryption keys, etc.).

Reference: https://docs.microsoft.com/en-us/aspnet/web-forms/overview/deployment/visual-studio-web-deployment/web-config-transformations
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TDD in small, digestible chunks

Test-Driven Development becomes (necessarily) much more common as code bases grow larger, diverse and more mission critical. Every piece of logic that can be explained in your software's documentation should be testable.

Write the tests, then write the code to meet those conditions, refine, repeat

Though 100% code-coverage is rarely attainable, the closer to fully covered with unit and integration tests, the more secure and solidly structured the code will be. Moreover, the dependency nightmares that many teams wrestle with will be largely mitigated as code reliability checks take place daily when TDD is fully embraced and implemented well.

I am assuming you know the basics of "why" and "how" TDD is done. If TDD does not feel natural, you may want to check out the book Test-Driven Development by Kent Beck. Reading that, what was most impressionable to me and has aided my TDD development style are the following quotes:

"Return a constant and gradually replace constants with variables until you have the real code". -on testing complex functions or objects
 
 "Write tests you wish you had. If you don't- you will eventually break something while refactoring". -on code bases with limited test coverage.

Do not write a few large tests to evaluate multiple ideas/functions at once. Write many small tests that test something that can be said in one short sentence: "Password Reset form successfully sends Reset email to appropriate user".


Write all the tests you know you will need and the tests you wish you had. You will wind up with quite a lot of code, but also quite a lot of "proofs", and you will be able to more confidently add to and refactor your highly-maintainable TDD-developed code.
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