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Simple PHP7, SQLite3, and AJAX Tutorial

Simple PHP7, SQLite3, and AJAX Tutorial

Ajax and PHP
Ajax and PHP

Using PHP and AJAX can be somewhat confusing. But, the benefits are countless when it comes to doing web related projects. So, I wanted to do a simple tutorial/example of how to get things setup and how to do some basic insert and retrieval of data. For this project, I’m using PHP7, SQLite3, AJAX, Firefox, and Atom. You can use any browser with debugging options and any integrated development environment (IDE) or text editor you want. I choose SQLite3 as my database because it’s lightweight and good for applications that need a database.


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Setup

Creating The Layout & Files

Ultimately, my file and directory layout looks like this:

├── ajaxNphp  // This is my working dir
       ├── index.html
       ├── process.php
       └── resources
           └── server.db

The ajaxNphp folder is the root folder of this project. In this folder, we have a resources folder that holds the database and can hold CSS and JavaScript files among other stuff. ***Note: For this project, JavaScript and CSS are inline to the files! I’m trying to keep this as simple as possible.*** For this part, I recommend using the terminal since it can be faster and we will use it for some other stuff during this project. So, KEEP IT UP! Anyway, My project is located in my Downloads folder under the ajaxNphp folder.
So, I open a terminal and type:

cd ~/Downloads/ajaxNphp/

The tilda (~) means your home folder and the rest is pretty self explanatory. I then do:

mkdir resources && touch index.html process.php

This creates the resources directory where our database will go; if successful, it will then create our PHP and HTML files that we will use for the project. The next part is for us to actually install the tools so we can setup our database and start writing code.

The Tools

I’m using an Ubuntu based operating system so I’ll show the commands you need to get PHP7, SQLite3, and Firefox installed.

sudo apt-get install sqlite3 php-sqlite3 php firefox

OK, now let’s just check that we have the proper versions installed.

PHP Check

// This will somewhat cleanup the version info on retrieval
    php -v | awk '{ print $1 $2 }' | head -n1
    // I get PHP7.0.25-0ubuntu0.16.04.1 which is PHP 7.0.25, so I'm set.

SQLite Check

sqlite -version
    // I get 2.8.17
    
    // If you do too, try:
    sqlite3 -version
    // If you get a return, then you are set for SQLite3.
    // I get a return value so am set.

Ok, so now we need to determine an environment to work with. I recommend Atom because it has a robust set of plugins and themes that make it more pleasant to work with. You’ll need to get it through their website if you wish to use the same thing; but, any text editor will suit this project.

Setup The Database

OK, so we now need to setup a database that we can query and insert to by using AJAX, PHP7, and SQLite3. I hope you’ve kept your terminal open as we will now change directory (cd) into the resources directory and launch SQLite3. So, here is what we do:

cd resources/ && sqlite3 server.db

We will then be presented with:

SQLite version <Your SQLite3 Version>
    Enter ".help" for usage hints.
    sqlite>

If you are seeing this, then let’s go ahead and create our database. I setup three columns for this project and they are title, date, and link. Recall, I’m doing a movies database so the first is for movie titles. The second is for when it was released, and the third is the cover image. So let’s create the table in our database.
Simply do:

CREATE TABLE Movies(title MAX, date varchar(10), link MAX);

If it was successful, you should see NO ERRORS and if you run :

.tables

you’ll get it returned. MAX means that the field can take the largest string possible. The varchar(10) means the field is limited to ten characters. There are other data types such as ints, but we will ignore them for now. Now, let’s insert some initial movie data by doing these below commands one at a time. Make sure there is an ending semi-colon for each!

// Date is in MM/DD/YYYY format
    
    INSERT INTO Movies VALUES('Alien', '05/25/1979', 'https://images-na.ssl-images-amazon.com/images/I/61ujvw4OXNL._SX342_.jpg');
    
    INSERT INTO Movies VALUES('Contact', '07/11/1997', 'http://www.filmsgraded.com/posters/01/1/8/8/84a.jpg');
    
    INSERT INTO Movies VALUES('Paul', '03/18/2011', 'https://upload.wikimedia.org/wikipedia/en/thumb/9/96/Paul_poster.jpg/215px-Paul_poster.jpg');
    
    // Check your work
    SELECT * FROM Movies;
    // You should see the data you entered returned.
    
    // If so, then simply exit.
    .exit

Excellent! The commands are pretty simple to understand. They even give a hint of what is going on. We use “INSERT INTO” to start the insert process. We reference our “Movies” table we created and then pass “VALUES” which match up with our title, date, link table layout. We end each command with a semi-colon. Next, we need a server to process PHP commands, interpret our form data, retrieve our data, etc.

Setup The Server

There are many servers out there one can use and there are some servers that are for testing. If you want to see some options, read my post on Quick Test Servers. For this project, I’m using PHP’s built in server used for testing since it will process PHP and our HTML files.
If you’ve kept the terminal up do this:

cd .. && php -S 127.0.0.1:1212

It’s pretty straightforward for what we are doing here. We moved back to the top directory of the project using cd .. since we only moved down one directory, We then use the “php” command with “-S” as a switch to use its server. We give “-S” an argument of “localhost” (127.0.0.1) and a port of 1212. The port needs to be bigger than 1024 since any port lower and equal to that requires sudo to use. It then waits to process requests. We can use ctrl + c to kill the server which can be helpful for when we want to use ctrl + l to clear the terminal screen of any text output and restart. When your project is complete, you can omit the change directory command and just do the PHP et all part. Add an “&” to the command so that the process is persistent even if the terminal closes. Now, we are truly ready to code!

HTML

Our Basic HTML Template

Let’s start off with a basic HTML template that we will add to shortly:

<!DOCTYPE html>
    <html>
    <head>
    <meta charset="utf-8">
    <title>Test AJAX/PHP</title>
    
    <script type="text/javascript">
    </script>
    
    </head>
    <body>
    
    <h2>Save Movie Info</h2>
    <form action="process.php" method="post">
    <input type="text" title="Title" placeholder="Title" name="Title" value="">
    <input type="text" title="Date" placeholder="Date" name="Date" value="">
    <input type="text" title="Link" placeholder="Link" name="Link" value="">
    <input type="submit" name="saveInfo" value="Save">
    <button type="reset" value="Reset">Clear</button>
    </forn>
    
    
    <br/><br/>
    <h2>Search Movie Info</h2>
    <form>
    <input type="text" name="searchField"
    title="Search"
    placeholder="Search..."
    onkeyup="getData(this.value)"/>
    </form>
    <br/><br/>
    
    
    <div id="dynDataField"></div>
    </body>
    </html>

Let’s break this down. We have two forms with their own input fields. One form is used for saving new movie entries and the other searches the database and gets the data back. The form that saves new movie info has three fields and a submit button. The three fields correspond to the three columns in our database and Movies table. The submit action uses the forms submit action to send our process.php script POST data about the form for processing.

The search form has one input field and an onkeyup event that calls a function called “getData”. This function has a parameter passed to it of “this.value” which will take the query that one has typed in. AJAX will be used in this instance to get data from the server as we type in a character. We have a div tag with an ID of “dynDataField” that we will reference to insert the returned data from the server. This is our bare bones HTML. But, it is pretty useless. Clicking any of the buttons or typing a search does nothing. So, let’s create an AJAX script to get our already entered data!

AJAX

AJAX Search Script

At the heart of AJAX, there are 4 core steps for GET and 5 core steps for POST.

  1. Create an XMLHttpRequest object
  2. Setup an onreadystatechange function for the XMLHttpRequest object
  3. Open a connection with the XMLHttpRequest object
  4. With POST: Setup a setRequestHeader with an XMLHttpRequest object
  5. Send the data with an XMLHttpRequest object
    // Step 1: Create object
    var xhttp = new XMLHttpRequest();  // Create the xhttp object
    // Step 2: Setup an onreadystatechange function for the XMLHttpRequest object
    // This is actually run after send is done and the server spits out info.
    xhttp.onreadystatechange = function() {
        // Confirm we have a  successful connection. Then, receive the response info.
        // For PHP it is echo that sends it.
        // Loops seem to cause this to wait which means an array can be traversed
        // and the output could be written as a table, etc.
        if (this.readyState == 4 && this.status == 200) {
            // do something with the returned data
        }
    };
    // Step 3: Open connection
    // More or less, open a connection: @Params POST or GET, path to XML page or php script, set async t/f
    xhttp.open("GET", "process.php", true);
    // Step 4: Send the data and let server process it.
    //         After done processing it, onreadystatechange is triggered.
    xhttp.send();    // Start the process and send GET data
    
    
    //      For POST do and add these changes
    //  xhttp.open("POST", "process.php", true);
    // Used in POST to setup data types like JSON, XML, etc... MUST BE DONE AFTER OPEN
    // xhttp.setRequestHeader("Content-type", "application/x-www-form-urlencoded");
    // Example data structure for Sending POST with above RequestHeader. See that this mimics GET
    // xhttp.send("fname=Henry&lname=Ford");
    // xhttp.sebnd(formData);  // Can use a string variable with formatted data structure instead

The above is the process. Here is what we setup in our scripts tag that’s in the head tag:

function getData(query) {
    if (query == "") {
        document.getElementById("dynDataField").innerHTML = "<p></p>";
        return;
    } else {
        var xhttp = new XMLHttpRequest();  // Create the xhttp object
        var formData = "dbQuery=" + query; // Our query being setup for processing
        // This is actually run after open and send are done
        xhttp.onreadystatechange = function() {
            if (this.readyState == 4 && this.status == 200) {
                updatePage(this);  // Send the returned data to further process
            }
        };
        xhttp.open("POST", "process.php", true);  // Open the connection
        xhttp.setRequestHeader("Content-type", "application/x-www-form-urlencoded");
        xhttp.send(formData);    // Start the process
        
    }
}

function updatePage(returnData) {
    // Get the echoed data and insert to div of dynDataField
    document.getElementById("dynDataField").innerHTML = returnData.responseText;
}

OK, so we have two functions here. One is for getting the data and the other inserts the results into our div. Get data checks to see if the input field is empty and if so leaves things as they are. If there is data in the field, it is then inserted into a variable “formData” and tied in with “dbQuery=”. This is what PHP will look at and use to insert into a database query. We then setup a statechange listener to wait for the server to finish processing the search and we send the result to the other function.

After this setup part, we do the standard open process but use POST instead of GET. Then, we tell the server what kind of data this is. Recall, GET defines it for us but is limited and less secure while POST has more data formats and better security but we have to define it using the setrequestheader. We then send the data in its formatted string to the server for processing. This w3schools link has some more info about each part. In this instance, the PHP script transfers a string back to the requester. Note, we can transfer JSON, XML, and other data. But, a string or “responseText” is good for now.

Alright, all that’s left is to write our PHP script to process the search and our insert to table option.

PHP

Base PHP

We have three core parts for the PHP project. We want to determine which form sent the POST. We then call one of two functions. One function will search the database. The other function will insert to the database.
Here is the basic setup:

<?php
    
    // Retrieve data
    function searchDB($QUERY) {
    }
    
    // Save new entry
    function saveInfo($TITLE, $DATE, $INFOLINK) {
    }
    
    // Determin action
    if(isset($_POST['saveInfo'])) {
        saveInfo($_POST["Title"], $_POST["Date"], $_POST["Link"]);
    } elseif (isset($_POST['dbQuery'])) {
        searchDB($_POST['dbQuery']);
    } else {
        echo "<h2 style='width:100%;background-color:#ff0000;color:#ffffff;text-align:center;'>Error! Illegal Access Method!</h2>";
    }
    
    ?>

The part of interest here is the the determine action section. This is how we determine which function to call when a form is submitted or an AJAX call is made. If neither call the script, we drop an error and exit the script. We are simply checking if “saveInfo” or “dbQuery” are set. We then call the proper function and pass the data that is sent. Let’s now setup our search function.

Search Function

As you might have seen, we are calling our search function “searchDB” and we are passing the “dbQuery” value to it.
So let’s see how we connect to the database and return data:

try {
    $serverPDO = new SQLite3('resources/server.db');
    $query = "SELECT * FROM Movies WHERE title LIKE '%" . $QUERY . "%' OR " .
    "date LIKE '%" . $QUERY . "%' OR " .
    "link LIKE '%" . $QUERY . "%'";
    $result = $serverPDO->query($query);
    
    while ($row = $result->fetchArray()) {
        echo "<div style='float: left;margin-left: 1em; margin-right: 1em;'>" .
        "<a href=" . $row["link"] ." target='blank'>" .
        "<img style='width:8em; height:10em;' src='" . $row["link"] . "'/></a><br/>" .
        "Title: " . $row["title"] .
        "<br/>Date: " . $row["date"] . "</div>";
    }
    
    if ($result->fetchArray() == 0) {
        echo "<div style='float:left;width:100%; background-color:pink;color:#ffffff;text-align:center;'>Nothing Found...</div>";
    } else {
        echo "<div style='float:left;margin-top:2em;width:100%; background-color:lightgreen;color:#ffffff;text-align:center;'>Search Completed...</div>";
    }
} catch (Exception $e) {
    echo "<h2 style='width:100%; background-color:ff0000;color:#ffffff;text-align:center;'>Error!</h2><br/>" . $e;
}

Let’s break this down. In our “searchDB” function, we have a try catch block that checks any exception that might occur. Technically, we really should be more specific to what exceptions might occur but for now, this will suffice. We try to create an SQLite3 database object and give it a local path name of “resources/server.db”. This is set to the “serverPDO” variable. We then create a “query” variable of type string that comprises of an SQL command that very broadly makes the database look at he table and see if any field matches the query. Please note, this is a very in-efficient way to do this as it looks at each field and then sees if any part is like the query both in upper, lower, and mixed casing. If we were being efficient, we’d base our queries on the columns and have either multiple input fields for the search with a “submit” button or use other techniques to keep the searches quick. Since this is a small database, performance isn’t poor and we can get away with this in a general context. Take note that the VALUES section is ordered just like we ordered it when we created the table columns.

Anyway, we then execute the query and get the result set into the “result” variable. This is essentially a 2D array that comprises an array of result objects that then have an array of values for each object. This is why we use the while loop and access the “row” and then any values there in. We assign the values to a string formatted with HTML markup that is then echoed. After that, we echo whether we traversed an arrays by saying the search was or was not found.

As I understand it, the “onreadystatechange” is triggered after the script is finished. So, all echos are collected by “onreadystatechange” and once the script sends an exit code the “onreadystatechange” sends what was echoed to whatever you setup to collect and parse the data.

Insert Function

As you can tell, our insert function will take three paramets which are the title, date, and link.

if ($TITLE != "" && $DATE != "" && $INFOLINK != "") {
    try {
        $serverPDO = new SQLite3('resources/server.db');
        $command = "INSERT INTO Movies VALUES('" . $TITLE . "','" . $DATE . "','" . $INFOLINK . "')";
        $serverPDO->exec($command);
        
        echo "<h2 style='width:100%;background-color:#0000ff;color:#ffffff;text-align:center;'>Inserted to db...</h2><br/>" .
        "Title: " . $TITLE . "<br/>Date: " . $DATE . "<br/>Link: " . $INFOLINK;
    } catch (Exception $e) {
        echo "<h2 style='width:100%; background-color:ff0000;color:#ffffff;text-align:center;'>Error! Database Insert Failed...</h2><br/>" . $e;
    }
} else {
    echo "<h2 style='width:100%; background-color:ff0000;color:#ffffff;text-align:center;'>Error!</h2><br/>" .
    "<h3>A field is empty...</h3>" . $e;
}

Lets break this down. The first parts are pretty much the same as the search function with the exception of execute than query being the command. We also confirm that each field is filled and if not we generate an error HTML markup. We have a try catch block if they are filled. In the try section, we connect to the database. We create a “command” of type string that inserts the sent data from the form. We then echo a success or failure message. Take note that this insert process is not AJAX. Our page will redirect to the process.php file and the file will output HTML. I’m doing it this way to show you two ways of processing data and why AJAX is useful in that we aren’t being redirected. As you can see, it’s a much cleaner user experience to use AJAX and this PHP example shows why. You can change this to AJAX but I will leave that to you to figure out how.

Conclusion

Discussion

We are DONE! Pat yourself on the back and get a cold beer or favorite beverage. You now have new possibilities available to you since you understand the basic concepts. Let’s do a quick recap and talk about pitfalls and the next steps one should take.

We start off by creating two files and one sub-folder. We then install our needed programs and a development environment. From there, we create our database in the sub-folder and the table in the database. It is important to recall that one of the fields is limited to a string size of 10. Anyway, we then entered some initial data so we could work with it after creating our code. After launching our PHP server, we create our initial HTML markup and talk about what we will do next. Next, we create our AJAX search script that checks against empties and so on. Since the HTML is done, we move on to the PHP. In the PHP, we check what’s sending the request and determine the necessary action from the POST data. We create our two functions and their logic which get called after the initial checks. Once the script exits, our AJAX sees this and we end the data to a function that then inserts the data to a div tag OR we get an HTML output in the case of the data insert form. We then drink our beverage and think about pitfalls and the next project we will do based off the work done here.

Pitfalls

The first massive pitfall is that we aren’t sanitizing our data. NEVER do a production project without cleaning input data! I skipped it here because I’m lazy and this article would get longer than I want it to. It can be pretty easy to do though since there are libraries out there one can use. You should use a JavaScript library or your own scripts to check the input. I recommend checking through the server too but the JavaScript should get most issues.

The next pitfall is that we aren’t checking the length of the date field. This can be done through JavaScript too and PHP can cover the process too. So, this would be one of the next steps to do as well as the above input sanitation.

The next pitfall is that the search function implements a poor query structure. I mentioned this before but we are collating things to keep in mind so I mention it here too.

I’m sure there are some other things of note but these three are the biggies. Let’s look at what our next steps might be with such a project.

Next Steps

    Here are some next steps to consider.

  • New Projects:
      • Use cookies to create a login system and account control to then access or create users for the database.
      • Use cookies and AJAX to create a tracking system that’ll insert data to the database about links clicked.
      • Create a meta search engine.
      • Create a password manager..
  • Improve Current Project:
      • Sanitize input fields to avoid exploits and future errors.
      • Implement a date field length check.
      • Make a better search system.

Result Images

ajax and php result
ajax and php result
ajax and php result 2
ajax and php result 2
error handling
error handling
error handling 2
error handling 2
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db insert
HTML, CSS, JavaScript Useful Cheat Sheet!

HTML, CSS, JavaScript Useful Cheat Sheet!


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Web Technologies
Web Technologies

I love web technologies because they provide a quick return on interest (ROI) and for the beginner gives immediate feedback in terms of accomplishment and sense of progress. There are many frameworks that one can use for a web based project but knowing the base elements these frameworks are comprised from is still important. Here is a reference list/cheat sheet of some of the most common HTML tags, CSS, and JavaScript one will likely use. This is great for Web Devs, Web Admins, coders, programmers, and the like.

HTML Tags

Most HTML tags are setup as open and close tags. This means that most tags are a pare/set and denote where they start and end. The end tag has a forward slash (/) to indicate the tag is the end tag.

<tag>Stuff in tag...</tag>
(open tag)content(/end tag)

<!--Some tags end like this-->
<tag/>

<div>

Div tags are considered devision tags and are used to section data on a page. CSS will then be used to style the tag by setting its position, setting the background color, setting the text color, etc. Think of the div as a container and your scaffolding for the page. Div tags are block elements.

<p>

The P tag stands for paragraph tag and this is like a sub container for the div tag. It often holds text but can contain images, links, and other non-block tags. Browsers will automatically add some space (margin) before and after each <p> element. This behavior can be modified with CSS using the margin properties. P tags are block elements.

<span>

The span tag is pretty much like the div tag. The difference between the two is that div is a block element which puts it on a separate line. A span tag, however, is an inline element, meaning that it can be on a line with other elements.


<img>

The img tag stands for images. People like images and I like images.

<img src="https://www.itdominator.com/wp-content/uploads/2017/07/wp-cli.jpg" alt="If image doesn't render, this text will show instead." />

<a>

Anchor tags link to parts on the same page or to new pages entirely. They are essentially links.

<!--To an external page...-->
<a href="http://www.google.com" target="_blank">Google</a>

<!--This will jump to the content that is wrapped with another anchor tag on the same page.-->
<a href="#colors">Colors</a>

<a name="colors">
<p>Colors are cool. The primary colors are red, green, and blue.</p>
</a>

<table>

Table is a block element that denotes there will be sub elements of th, tr, td. There are others but these are the core parts. Th stands for table header and
is inset within a tr (table row). Tr is table row which makes a row for the table. Td is table data which is like a column and is inset in a table row too.

border-collapse: separate (default):

Firstname Lastname
Tom Gar
Lois Griffin

border-collapse: collapse:

Firstname Lastname
Peter Griffin
Lois Matt

form

A form is used to submit data to the server. There are many form objects one can use. Below is a table covering all HTML5 form objects and their code and examples.

Object Preview HTML 5 code
Label

<label>Texte</label>
Button

<input type=”button” name=”name” value=”Bouton”>
Image button


<input type=”image” src=”image/bimage.jpg”>
Text field

<input type=”text” name=”text” value=”empty”>
Password

<input type=”password” name=”monpass” value=”12345″>
Date

<input type=”date” name=”date” value=”<?php echo $today?>”>
Date and time

<input type=”datetime” name=”time” value=”<?php echo $now?>”>
Time <time>2013-06-27</time>
Number

<input type=”number” name=”num” value=”12345″>
Color

<input type=”color” name=”color” value=””>
Search input

<input type=”search” name=”” list=”datalist” value=””>
Data
Dix
<data value=”10″>Ten</data>
Check box

<input type=”checkbox” name=”checkbox1″ value=”checkbox”>
Radio group



<label>Choice 1
<input type=”radio” name=”radio1″ value=”radio1″>
</label>
<label>Choice 2
<input type=”radio” name=”radio1″ value=”radio2″>
</label>
Textarea

<textarea name=”textarea”>content</textarea>
Range


<input type=”range” min=”-100″ max=”100″
value=”0″ step=”2″ name=”power” list=”powers”>
<datalist id=”powers”>
<option value=”0″>
<option value=”-30″>
<option value=”30″>
<option value=”+50″>
</datalist>
Data list To be used with input
<datalist id=”identifier”>
<option value=”1″>
<option value=”2″>
<option value=”3″>
</datalist>
Select

<select name=”select”>
<option>Alpha</option>
<option>Beta</option>
<option>Delta</option>
</select>
Select list

<select name=”select2″ size=”3″>
<option>Alpha</option>
<option>Beta</option>
<option>Delta</option>
</select>
Menu

  • New
  • Open
  • Save
  • <menu type=”context”>
    <li>New</li>
    <li>Open</li>
    <li>Save</li>
    </menu>
    Toolbar

  • <menu type=”toolbar”>
    <li><button type=”button” onclick=”fnew()”>New</button></li>
    <li><button type=”button” onclick=”fopen()”>Open</button></li>
    <li><button type=”button” onclick=”fsave()”>Save</button></li>
    </menu>
    Combo box


    <input type=”text” list=”comboid”>
    <datalist id=”comboid”>
    <option value=”0″>
    <option value=”-30″>
    <option value=”30″>
    <option value=”+50″>
    </datalist>
    File upload

    <input type=”file” name=”file”>
    Image & caption

    Caption

    <figure>
    <img src=”image/image.gif”>
    <figcaption>Caption</figcaption>
    </figure>
    Fieldset
    Title

    …Content…

    <fieldset>
    <legend>Title </legend>

    <p>Content</p>
    </fieldset>

    Output

    <output onforminput=”value = 2 + 2″></output>
    Meter
    12 units
    <meter min=0 max=24 value=12>12 units</meter>
    Progress 0%
    <progress id=”prog” max=100>
    Summary

    Overview
    term
    definition

    <details>
    <summary>
    Presentation
    </summary>
    <dl>
    <dt>term</dt>
    <dd>definition</dd>

    </dl>
    </details>

    Submit button

    <input type=”submit” name=”submit” value=”Submit”>
    Clear/Reset button

    <input type=”reset” name=”clear” value=”Clear”>

    HTML Entities

    HTML entities are used in place of reserved characters in HTML. Characters that are not present on your keyboard can also be replaced by entities as well. The most common are listed in a table below.

    Result Description Entity Name Entity Number
    non-breaking space &nbsp; &#160;
    < less than &lt; &#60;
    > greater than &gt; &#62;
    & ampersand &amp; &#38;
    double quotation mark &quot; &#34;
    single quotation mark (apostrophe) &apos; &#39;
    ¢ cent &cent; &#162;
    £ pound &pound; &#163;
    ¥ yen &yen; &#165;
    euro &euro; &#8364;
    © copyright &copy; &#169;
    ® registered trademark &reg; &#174;

    HTML Notes

    Recommended Default HTML Markup Before Content Is Added

    <!DOCTYPE html> <!--Tells a browser its an html page-->
    <html lang="en">
    <head>
      <meta charset="utf-8">  <!--Encoding model-->
      <title>Title seen on its tab</title>
      <link rel="stylesheet" href="/css/master.css"> <!-- Attach CSS through a path -->
    
    
    
    
    </head>
    <body>
    
    <!-- content goes here... -->
    
    
    <script src="resources/scripts/script.js" charset="utf-8"></script>  <!-- Attach Javascript File through path -->
    </body>
    </html>
    

    Block Elements

    In general, HTML elements can be divided into two categories : block level and inline elements. HTML block level elements can appear in the body of an HTML page. It can contain another block level as well as inline elements. By default, block-level elements begin on new lines. Block level elements create larger structures (than inline elements).

    • p
    • h1, h2, h3, h4, h5, h6
    • ol, ul
    • pre
    • address
    • blockquote
    • dl
    • div
    • fieldset
    • form
    • hr
    • noscript
    • table

    Inline Elements

    HTML inline elements can appear in the body of an HTML page. They can contain data and other inline elements. By default, inline elements do not begin on new lines. Inline elements create shorter structures (than block elements).

    • b, big, i, small, tt
    • abbr, acronym, cite, code, dfn, em, kbd, strong, samp, var
    • a, bdo, br, img, map, object, q, script, span, sub, sup
    • button, input, label, select, textarea

    Margins

    Margins are the spacing around an element.

    This span tag has 2em margin set…

    Padding

    Padding is the spacing internal to an element and its “walls”.

    This span tag has 2em padding set…

    CSS

    Examples/Logic

    Selector Example Example description
    .class .intro Selects all elements with class=”intro”
    #id #firstname Selects the element with id=”firstname”
    * * Selects all elements
    element p Selects all <p> elements
    element,element div, p Selects all <div> elements and all <p> elements
    element element div p Selects all <p> elements inside <div> elements
    element>element div > p Selects all <p> elements where the parent is a <div> element
    element+element div + p Selects all <p> elements that are placed immediately after <div> elements
    element1~element2 p ~ ul Selects every <ul> element that are preceded by a <p> element
    [attribute] [target] Selects all elements with a target attribute
    [attribute=value] [target=_blank] Selects all elements with target=”_blank”
    [attribute~=value] [title~=flower] Selects all elements with a title attribute containing the word “flower”
    [attribute|=value] [lang|=en] Selects all elements with a lang attribute value starting with “en”
    [attribute^=value] a[href^=”https”] Selects every <a> element whose href attribute value begins with “https”
    [attribute$=value] a[href$=”.pdf”] Selects every <a> element whose href attribute value ends with “.pdf”
    [attribute*=value] a[href*=”w3schools”] Selects every <a> element whose href attribute value contains the substring “w3schools”
    :active a:active Selects the active link
    ::after p::after Insert something after the content of each <p> element
    ::before p::before Insert something before the content of each <p> element
    :checked input:checked Selects every checked <input> element
    :disabled input:disabled Selects every disabled <input> element
    :empty p:empty Selects every <p> element that has no children (including text nodes)
    :enabled input:enabled Selects every enabled <input> element
    :first-child p:first-child Selects every <p> element that is the first child of its parent
    ::first-letter p::first-letter Selects the first letter of every <p> element
    ::first-line p::first-line Selects the first line of every <p> element
    ype.asp”>:first-of-type p:first-of-type Selects every <p> element that is the first <p> element of its parent
    :focus input:focus Selects the input element which has focus
    :hover a:hover Selects links on mouse over
    sp”>:in-range input:in-range Selects input elements with a value within a specified range
    :invalid input:invalid Selects all input elements with an invalid value
    :lang(language) p:lang(it) Selects every <p> element with a lang attribute equal to “it” (Italian)
    sp”>:last-child p:last-child Selects every <p> element that is the last child of its parent
    ype.asp”>:last-of-type p:last-of-type Selects every <p> element that is the last <p> element of its parent
    :link a:link Selects all unvisited links
    :not(selector) :not(p) Selects every element that is not a <p> element
    sp”>:nth-child(n) p:nth-child(2) Selects every <p> element that is the second child of its parent
    hild.asp”>:nth-last-child(n) p:nth-last-child(2) Selects every <p> element that is the second child of its parent, counting from the last child
    f-type.asp”>:nth-last-of-type(n) p:nth-last-of-type(2) Selects every <p> element that is the second <p> element of its parent, counting from the last child
    ype.asp”>:nth-of-type(n) p:nth-of-type(2) Selects every <p> element that is the second <p> element of its parent
    ype.asp”>:only-of-type p:only-of-type Selects every <p> element that is the only <p> element of its parent
    sp”>:only-child p:only-child Selects every <p> element that is the only child of its parent
    :optional input:optional Selects input elements with no “required” attribute
    ange.asp”>:out-of-range input:out-of-range Selects input elements with a value outside a specified range
    sp”>:read-only input:read-only Selects input elements with the “readonly” attribute specified
    sp”>:read-write input:read-write Selects input elements with the “readonly” attribute NOT specified
    :required input:required Selects input elements with the “required” attribute specified
    :root :root Selects the document’s root element
    ::selection ::selection Selects the portion of an element that is selected by a user
    :target #news:target Selects the current active #news element (clicked on a URL containing that anchor name)
    :valid input:valid Selects all input elements with a valid value
    :visited a:visited Selects all visited links

    IDs

    ID selectors are supposed to be unique within the HTML document. When queried with JavaScript it should return a single element but it can return an array/list if the web developer set the document with multiple IDs of the same type. Standards dictate this is poor form if done.

    <!-- The IDs are arbitrary. -->
    
    <div id="left-container"> <!-- Content --> </>
    <div id="middle-container"> <!-- Content --> </>
    <div id="right-container"> <!-- Content --> </>
    

    Classes

    Class selectors don’t have to be unique within the HTML document. When queried with JavaScript it usually returns an array/list.

    <!-- The Class is arbitrary. -->
    
    <div class="book"> <!-- Content --> </>
    <div class="book"> <!-- Content --> </>
    <div class="book"> <!-- Content --> </>
    

    CSS Button Generator Button Generator

    Quickly make buttons…

    Button













    JavaScript

    Get Elements By ID/Class/TagName/CSS Selector

    Getting elements by id, class, and tag among other options is a sizeable chunk of the JavaScripting one will do. This allows us to interact with the DOM

    // Get HTML element(s) with specified id.
      var x = document.getElementById('id');
    
    // Get HTML elements with specified class.
      var x = document.getElementsByClassName('className');
    
    // Get HTML elements with specified tag.
      var x = document.getElementsByTagName('tagName');
    
    // Get HTML elements tht matches a specified CSS selector
    // This example returns a list of all  elements with class="icon".
      var x = document.querySelectorAll("img.icon"); 
    

    Function

    The basic block of coding we all know and have come to love. Yes…the function.

    function sum(a, b) {
        return a + b;      // The function returns the sum of a and b
    }
    var sumVal = sum(2,4);
    alert(sumVal);  // Will pop-up saying 6
    

    If Statement

    Check the conditions.

    if (condition) {
    }
    

    Loops

    Loops baby, they’re needed and these will meet your needs.

    // Standard loop
    for (var i=0; i<array.length; i++) {
       array[i].innerHTML;
    }
    
    // For In Loop
    for (var tag in elements) {
        // Do stuff while there are tags to work on
    }
    
    // While Loop
    while (condition) {
        // Do stuff while condition is met
    }
    
    // Do While
     do {
        // One at least one and keep doing stuff while condition is met
    }
    while (condition);
    

    Switch/Case Statement

    Good for menu stuff, switch/case statements are ready for the job.

    var day;
    switch (new Date().getDay()) {
        case 0:
            day = "Sunday";
            break;
        case 1:
            day = "Monday";
            break;
        case 2:
            day = "Tuesday";
            break;
        case 3:
            day = "Wednesday";
            break;
        case 4:
            day = "Thursday";
            break;
        case 5:
            day = "Friday";
            break;
        case  6:
            day = "Saturday";
    }
    alert(day);
    

    Alert & Console Log

    Error logging is helpful. The two way to do this are through alerts and console logging. Most of the time, alert isn’t used but it can be helpful to warn the user, etc.

    // This will generate a pop-up window with the "Hello, World!" text.
    alert("Hello, World!");
    
    // This will log to the console the "Hello, World!" text.
    To access the console in Firefox, do Ctrl+Shift+J
    console.log("Hello, World!");
    

    Adding Event Listeners

    Event listeners are the next most important after getting an element. They allow us to let the user click on stuff or interact through other ways in order to create dynamic interactions.

    // This attaches a click event to the entire DOM.
    // We can then check which IDs, Classes, etc were clicked to then do other things.
    
    document.addEventListener("click", (e) => {
        if(e.target.id == "alert2")
            alert("You clicked an element with the ID of alert2");
    
    });
    
    
    // This attaches to a specific element with the ID of cars and
    // when clicked alerts us to the innerHTML text.
    
    <p id="cars">Hello, World!</p>
    
    document.getElementById('cars').addEventListener("click", (e) => {
            alert("The content is:  " + e.target.innerHTML);
    });
    
    // This attaches it in a different manner.
    document.getElementById('cars').onclick =  function(){
        // do stuff
    }
    
    // You can add it though a tag as well.
    <div onclick="myFunction()"> I am clickable! </div>
    

    Here is a list of some common HTML event attributes:

    Event Description
    onchange An HTML element has been changed
    onclick The user clicks an HTML element
    onmouseover The user moves the mouse over an HTML element
    onmouseout The user moves the mouse away from an HTML element
    onkeydown The user pushes a keyboard key
    onkeyup The user releases a keyboard key
    onload The browser has finished loading the page

    Arrays

    Arrays in JavaScript are a special object and really act like lists or vectors since we can push new values to it.

    // An empty array
    var cars = [];
    
    // Has nodes/objects
    var cars = ["Toyota", "Sab", "Mazda"];
    
    // Add to array
    cars.push("Nesan');
    
    // Remove from end of array
    cars.pop();
    

    Parent Element

    Sometimes, we need to access the element that contains the element we accessed. This could be because we want to remove the element or we want to add something next to it than in it.

    <div>
        <p id="cars" >
            Cars are cool.
        </p>
    But boats are even more cool.
    </div>
    
    var x = document.getElementById('cars').parentElement;
    alert(x.innerHTML);  // This will present an alert box with "But boats are even more cool."
    
    
    // This will remove the element we accessed from the div
    var childElm = document.getElementById('cars');
    var parentElm = childElm.parentElement;
    
    parentElm.removeChild(childElm);
    

    Cookies

    Sometimes, we need to store user information for later usage. This is where cookies come in.

    function saveAsCookie() {
        var uName = document.getElementsByName("userName")[0].value;
        var eml = document.getElementsByName("email")[0].value;
    
    
        // should set expires date: Ex -> expires=(UTC date).
        // Use secure; in argument to make sure it only transports across HTTPS or secure connections
        document.cookie = "username=" + uName  +"; path=" + document.URL;
        document.cookie = "email=" + eml + "; path=" + document.URL;
    }
    
    function displayCookies() {
        var cookiesField = document.getElementById("cookieField");
        var cookies = document.cookie.split(";");  // Set as an array to traverse....
    
        for (var i=0; i<cookies.length; i++) {
            cookiesField.innerHTML += cookies[i] + "<br/>";
        }
    }
    
    function clerCookies() {
        var expireDate = "Thu, 01 Jan 1970 00:00:00 UTC";
        document.cookie = "username=; expires=" + expireDate;
        document.cookie = "email=; expires= " + expireDate;
    }
    
    <form>
    <input type="text" title="User Name" name="userName" placeholder="User Name" value=""/>
    <input type="text" title="Email" name="email" placeholder="Email" value=""/>
    <input type="button" name="submit"  onclick="saveAsCookie()" value="loginSubmit">
    </form>
    
    <button type="button" name="button" onclick="displayCookies()">Get Cookie</button>
    <button type="button" name="button" onclick="clerCookies()">Clear Cookie</button>
    
    <div id="cookieField"></div>
    

    AJAX

    AJAX is a developer’s dream, because you can:

    • Update a web page without reloading the page
    • Request data from a server – after the page has loaded
    • Receive data from a server – after the page has loaded
    • Send data to a server – in the background
    function loadDoc() {
      var xhttp = new XMLHttpRequest();        // Create the xhttp object
      xhttp.onreadystatechange = function() {  // This is actually run after open and send are done
        if (this.readyState == 4 && this.status == 200) {  // Confirm we have a  successful connection
         // Receive the response info. For PHP it is echo that sends it. Then set into demo div
         document.getElementById("demo").innerHTML = this.responseText;  
        }
      };
      xhttp.open("GET", "ajax_info.txt", true);  // post or get, path to XML page or php script, set async 
      xhttp.send();                              // Start the process
    }
    
    
    <button type="button" name="button" onclick="loadDoc()">Load XML</button>
    <div id="demo">
    

    String Manipulation

    String Manipulation can be important when handling cookies or data. Sometimes we need to split it into an array, make it lower case or vise versa, find a sub string, or more.
    These should get you started:

    // Find sub string
    var str = "Hello world, welcome to the universe.";
    var n = str.includes("world");
    
    // Find sub string at offset
    var str = "Hello world, welcome to the universe.";
    var n = str.includes("world", 12);
    
    // Replace string 
    var str = "Windows!";
    var res = str.replace("Windows", "Linux");  // old value, new value
    
    // Replace all case sensitive
    var str = "Mr Blue has a blue house and a blue car";
    var res = str.replace(/blue/g, "red");
    
    // Replace all case-insensitive
    var str = "Mr Blue has a blue house and a blue car";
    var res = str.replace(/blue/gi, "red");
    
    // String split
    var str = "How are you doing today?";
    var arry = str.split(" ");  // Split by spaces
    
    // To Upper
    var x = "Linux";
    x.toUpperCase();
    
    // To Lower
    var x = "LINUX";
    x.toLowerCase();
    

    Conclusion

    I think this list is pretty good and fits most user’s needs. This should definitely help those who are looking for a certain tag or CSS logic or are just wanting to see a broad selection of what web technologies are based off of. Coders, website developers, Admins, etc should have most of what they need right on the page with good samples to start. Leave a commemt if you’d like me to add something else! Anyway, if you liked this reference sheet/cheat sheet, start using what you have learned by setting up a quick test server! Read my article by clicking the below image!


    Servers


    The Developers Dilemma

    The Developers Dilemma

    Atom Text Editor With Code
    Code In Atom

    I’ve been programming for a while now and am enjoying the process a lot. The challenges, the mental stretches, and the success of seeing one’s dreams and ideas come to fruition can only be experienced rather than explained. Still, not all is wonderful throughout the process. For instance, choosing an IDE, Integrated Development Environment, can and often is an ordeal in and of itself. Each developer has questions and they need to have answers. What is the size of the program? Does it have syntax highlighting? How quickly does it launch? Is it open source? What programming languages work best with it?

    Visual Studio is about 4GB in size and launches slower than molasses falling from a container. DevC++ is about 500MB and launches in half the time Visual Studio does. Finally, Geany, it’s smaller than 120MB and launches faster than ether of them. We then have others like Netbeans, Code:Blocks, Eclipse, and many many more filling the rosters. Still, I have not found an environment that I love and would rave over. Rather, I have one or two that I tolerate and the rest I despise. This is frustrating and has dampened my enjoyment of programming to varying degrees during different situations. I will say that I’m picky though and at times am probably not using an environment to its fullest to better appreciate it. Nevertheless, there should be a half-way point where concessions are made on both sides.

    For instance, I will accept a larger program with more features providing it doesn’t take a decade to launch. Or, I will accept fewer supported programming languages for syntax highlighting, etc. To meet my requirements and needs I’ve taken a slightly different approach to tackle my dilemma. With the exception of Geany, I don’t actually use the above IDEs. I stick to text editors such as gEdit, gVim, Vim, Geany, and Nano. This greatly reduces the disk space a lotted to my IDE as I only need one of the programs. These editors have varying features and different skill requirements too: caugh, vim, caugh. I generally stick with Geany and then Vim as my auxiliary editor which keeps everything light, fast, and colored. But I want more! I need more! I need sub-panes, tree views, integrated terminals, and so on! What a plight!

    Geany has only two panes to work with and even then it’s clunky. The other editors don’t have secondary panes at all. Geany also allows for a single terminal sub-sub-pane. I need more than that and so I ended up finding Sublime. It’s a text editor with nearly everything I want. It really impresses me and I thought it couldn’t get any better as it has multi-panes for code, tree views, etc. Still, it is lacking a few key features needed or wanted. Sublime isn’t open source and it hasn’t any integrated terminal support. I felt lost and still unhappy even in the marvel that is Sublime. I searched, hunted, and scrounged about until I found my holy grail of text editors! The feeling was like an atom bomb hitting me with its glorious radiation and blissfully passing me away to Nirvana. Ironically or with my skilled writing and metaphors, the name of the text editor matches my description. It’s called Atom. It is powerful and open source. My two favorite descriptors together at last!

    Atom is a programmer’s dream come true. It allows for multiple sub-panes and multiple sub-terminals to code quickly and easily. It supports syntax highlighting and directory views. Plug-ins allow for even more enhancements that I can’t even begin to imagine! Not only that, Atom is as fast and lightweight as Geany. All of this and more under an open source license! All my current needs and picky wants are met and there is a new horizon of options available to me that I can’t wait to explore! I hope everyone will find this diamond in the rough and enjoy it as much as I do!

    W3C Killed Web Security

    W3C Killed Web Security

    W3C Logo
    W3C Logo

    It’s a sad day folks…. The W3C killed web security by accepting DRM without having a caveat that protects against DMCA’s (Digital Millennium Copyright Act) unreasonable reach. Security researchers are out; hackers are in. While I am sure that most users believe that companies and creators have the right to protect their IP (Intellectual Property), I am also sure they believe in having strong security and a reasonable right to use their purchased product in whatever manner they see fit. With the web, it was a last bastion that held to those principles. It was killed both brutally and without much compunction by W3C and its corporate backers in a vain attempt to stem the tide of piracy and illegal copying.

    Let’s be clear here for a moment about the current problem. I don’t have an issue with DRM. I don’t agree with it all the time but neither do I disagree with it all the time. No, the issue is with DMCA and it’s unreasonable reach in trying and failing to protect DRM. There are two sections in the DMCA that are of great interest. The core section I am referring to is Section 1201: Circumvention of copyright protection systems.

    Section 1201 affects the web and all technologies the most and is why it is a sad day for the internet. The EFF letter to W3C addresses some of the concerns regarding Section 1201 in its implementation in web technologies.
    Here are some of the critical points they made when hoping W3C would add a pretext for accepting DRM standards.

    “This covenant would allow the W3C’s large corporate members to enforce their copyrights. Indeed, it kept intact every legal right to which entertainment companies, DRM vendors, and their business partners can otherwise lay claim. The compromise merely restricted their ability to use the W3C’s DRM to shut down legitimate activities, like research and modifications, that required circumvention of DRM….
    More directly, such a covenant would have helped protect the key stakeholders, present and future, who both depend on the openness of the Web, and who actively work to protect its safety and universality. It would offer some legal clarity for those who bypass DRM to engage in security research to find defects that would endanger billions of web users; or who automate the creation of enhanced, accessible video for people with disabilities; or who archive the Web for posterity. It would help protect new market entrants intent on creating competitive, innovative products, unimagined by the vendors locking down web video.”

    There is the crux of the issue and why W3C should have had clear stipulations for implementing DRM into web technologies. There really isn’t anything protecting the user and their right to circumvent DRM when it is not infringing the patent holder or IP source. Security experts are now in a quasi grey area where their work is to determine vulnerabilities but they are violating DMCA. This helps no one but the bad guys and that is just sad in the day and age where billions of users need strong security the most.

    In addition, we don’t know who did and didn’t vote in favor of the implementation of a DRM standard. The votes are secret and that should disturb us even more than the terrible overreach of DMCA’s rules. It is worth noting that W3C’s member votes aren’t always public and by default one must opt-in for public disclosure of said vote. For an organization that affects our lives, to not have public disclosure of votes by default and as enforced practice is egregious. We all know why this is the case though. Companies don’t want to look like the bad guys even when they are. So they hide in anonymity as we all are left to hang by their terrible decisions. We can make some guesses as to who voted for the standardization but don’t know who else are their accomplices. Essentially, a private group gets to affect our lives without us holding them accountable. In addition, their votes wont stop piracy or illegal copying. So all in all, they hurt themselves as well as us with nothing to show for it but the further stripping of our rights.

    While it all looks bad, there are bright spots. The US government is looking to open source its code base as much as it reasonably can. Maybe they’ll step in and decide obtrusive DRM and its protective DMCA rules are too powerful. If interested in some of their projects, check out my article covering some of the best packages released to date.

    Code.gov

    Code.gov

    Picture of code dot gov slogan
    Code.gov

    I just wanted to make a shout out to Code.gov and the work they do. If one isn’t sure of who or what they are they are the US government’s team working to opensource the code used by the government’s agencies. This post comes on the heals of an email I received from their mailing list which reminded me of their transition to open source their code. I can’t think of any better way to express democracy than through opening up a sizable chunk of ones code base.

    Here are 5 projects to keep an eye on


    5 — Consumer Financial Protection Bureau’s Owning a Home Project

    Hey, getting a home isn’t always easy but it can be with these tools provided by Consumer Financial Protection Bureau and its Owning a Home project. Everything is looked at from loan options, terminology, and costs.

    Link: https://github.com/cfpb/owning-a-home

    4 — National Archives and Records Administration’s File Analyzer Project

    So, this project came to my attention because I am programming a CSV file viewer. I’m considering other functions for my application and this file analyzer just might be the thing to give it a cool boost. It says that each file test generates a table of results and that is useful given my CSV viewer dumps a csv file into a GUI table view.

    Link: https://github.com/usnationalarchives/File-Analyzer

    3 — Department of Agriculture’s RIBD Project

    Ahh leisure…. Who doesn’t want to enjoy time off at beautiful federal lands, historic sites, museums, and/or other attractions?
    According to their site, the “Recreation Information Database (RIDB) provides data resources to citizens, offering a single point of access to information about recreational opportunities nationwide.”

    Link: https://usda.github.io/RIDB/

    2 — NSA’s Unfetter Project

    When not spying on us and the world, the NSA is helping us secure our data by giving tools that analyze gaps in our security posture.

    Link: https://iadgov.github.io/unfetter/

    1 — NASA’s 3D Resources

    I am a big fan of space and even bigger fan of making beautiful Blender renders. NASA’s 3D model collection is huge and gives great assets to space fans and art lovers alike to play with.

    Link: https://github.com/nasa/NASA-3D-Resources

    Top Resources For Distro Maintainers

    Top Resources For Distro Maintainers

    Distro Maintainer
    Distro Maintainers looking serious….

    There are great resources for a Linux distribution maintainer and here are a few of my favorite. Most sources are geared towards Ubuntu based systems but a few like the Themes and Window Managers links are more or less universal.

    Window Managers

    The first site deals with the plethora of window managers that are out there. XWinMan lists many managers ranging from session and full desktop managers to just the bare windows themselves. There are some that are deprecated so be weary; but, it still has many that are not!
                  Link:  http://www.xwinman.org/

    Source List Generator

    The next is a site that generates source list files for Ubuntu. This is really awesome for a number of reasons but the biggest for me is recovering from a bad dependency hell scenario. While it is rare, it is something that a maintainer and even a user needs to be aware of. Adding too many PPAs (which generally isn’t recommended) can cause loops and other strange and unexpected behavior from a package manager. In addition, the generator gives PPA info on a number of popular software this is not necessarily shipped with the system. It is well worth keeping in ones developer/user arsenal.
                  Link:  https://repogen.simplylinux.ch/index.php

    Themes

    This third link deals with themes, icons, backgrounds, etc. Who doesn’t like themes? Anyway, it has many of these to spruce up the system and make it less boring. I started using Gnome-Look early on in my Linux experience and it has yet to fail to find me something cool or aesthetically pleasing.
                  Link:  http://www.gnome-look.org/

    Debootstrap Versions

    This fourth link is geared towards building a Debian based distribution. Debootstrap is a great peace of software but needs the PPAs of the system it will setup in a subdirectory of ones system. This links provides the needed information.
                  Link:  http://packages.ubuntu.com/search?keywords=debootstrap&searchon=names&suite=all§ion=all

    Ubuntu-Mini-Remix

    This fifth link goes to a website that has minified Ubuntu ISOs. These are phenomenal for creating new distributions from pretty much scratch. It isn’t LFS kinda scratch but it’s as close as it’s likely to get.
                  Link:  http://www.ubuntu-mini-remix.org/

    Chrooting in and building up is the best way to do this. I have a video of the steps too:

    Package List

    This last link is great for doing source compiling. This can be used to find the install name of a package when an error output doesn’t give much of a hint. I must admit I only just recently heard of this page after attempting to compile a installer package. Going to the IRC of the developer was where I learned of this. It’s a bit embarrassing for not having known of this given how long I’ve been using various *nix systems. Still, I guess the old adage, “you can’t teach an old dog new tricks”, is proven wrong.
                  Link:  http://packages.ubuntu.com/

    Quick Test Server

    Quick Test Server

    Server

    There are times when I need a server in order to test some feature or bit of code. I don’t like spooling up a Linux, Apache, MySQL, and PHP (LAMP) or Linux, NGINX, MySQL, and PHP (LEMP) stack because it’s tedious. Notice what I did there? I made the whole sentence tedious to get you to think it really is tedious. It really isn’t but frankly, I needed a reason to write this. Anyway, so, what is one to do? Well, there are two option that come to mind and those are Python, PHP, or Netcat. One might ask: “Whaaat? Rly?”. Yup. Really. All one needs to do is open up a terminal/cli and get ta hackin.

    Python call up the Python module SimpleHTTPServer using the switch -m and then give it a port. Make the port greater than 1024 since those are reserved and require root to use. BAM! Open your browser of poison and go to localhost:portNumber or 127.0.0.1:portNumber.

    Python Server

    python -m SimpleHTTPServer 1337
    

    I did not need to insert any index.html files to the directory. Python automatically gives a list of the directory contents when no index file is found. As a side note, Python doesn’t seem to read Php properly. I have yet to get it to work.

    For PHP all one does is use the switch -S and then give it an address (127.0.0.1) and port. Again, make the port greater than 1024 since those are reserved and require root to use. BAM! Once more, open your browser of poison and go to localhost:portNumber or 127.0.0.1:portNumber.

    PHP Server

    php -S 127.0.0.1:1337
    

    It is worth noting that with PHP I had to insert an index.php file into the directory I ran the command from. It doesn’t generate any list but does throw an error when no index is found. Additionally, this method seems to only work with PHP files. To test if the PHP server works, simply insert in the index.PHP :

    <?php
        phpinfo();
    ?>
    

     

    For the last one we will look at Netcat. Netcat is the swiss army knife of the networking tools and has an interesting way of creating a kind of server. To start off, simply create a file called serve.sh. The name is arbitrary but that’s what we will use for this example. Then, in the file add

    Netcat Server

    #!/bin/bash
    
        echo "`cat index.html`"
    

    When this is done, simply create an index.html as you would any other. In my case, I did:

    <!DOCTYPE html>
    <html>
    <head>
        <meta charset="utf-8">
        <title>Google Link</title>
    </head>
    <body>
        <h1><a href="http://www.google.com">Google</a></h1>
    </body>
    </html>
    

    After all this prep, which isn’t much we simply run in the terminal where serve.sh and index.html is:

    while true; \
    do { \
        echo -e 'HTTP/1.1 200 OK\r\n'; sh serve.sh; \
    } | nc -l 1337; \
    done
    

    One might need to press enter again to actually run it because of the \’s stating “look to next line for rest of command”. One can also just remove the \’s and put the whole command like so:

    while true; do { echo -e 'HTTP/1.1 200 OK\r\n'; sh serve.sh; } | nc -l 1337; done
    

    One can use PHP with this by the way. All one does is rename index.html to index.php. Then one adds some code like in the PHP example above. After that, in the serve.sh, edit the cat index.php to be PHP index.php. This has PHP interpret the file which then has its output gets echoed back to the requester.
    All of this needs some explaining. So what is happening is that the while loop is checking to see if there is anything left to run. Note that the first part before the semicolon tells the browser that there is a server where one requested one. IE, it confirms the request. Then, the serve.sh is ran. In serve.sh it echos out what cat prints from index.html or what PHP prints from index.php. This is essentially sent as the file back to the requester. Thus, we can see the h1 sized Google anchor link in this example.

    Voila! A nice juicy server is ready for use in any project that needs one. If one is adventurous, one can use these simple servers to serve files on the local network. To do this, all you have to do is allow the port to accept connections using UFW and then change the address “127.0.0.1” to “0.0.0.0”. This isn’t recommended for long term use but can be useful when needing to transfer something or using an app that’s for the local network. Even then, one might be better off just using ssh or email! Still, in those rare times, all one does is allow the port to be open by using ufw.

    ufw allow portNumber/tcp
    

    To remove the rule:

    ufw status numbered
    ufw delete "the number associated with ones portNumber"