Web Developers Portal

Tuesday, 26 April 2022

SaaS (Software as a Service)

SaaS - Definition

The most complete cloud computing service model is one in which the computing hardware and software, as well as the solution itself, are provided by a vendor as a complete service offering.
SaaS is a model where an application is hosted on a remote data center and provided as a service to customers across the internet.
In this model the provider takes care of all software development, maintenance and upgrades.
Salesforce.com is a common and popular example of a CRM SaaS application.

Is it customizable?

Many people believe that SaaS software is not customizable, and in many SaaS applications this is indeed the case. eg: user-centric application like office suite
Many other SaaS solutions expose Application Programming Interfaces (API) to developers to allow them to create custom composite applications eg: Salesforce.com, Quicken.com, etc

So, SaaS does not necessarily mean that the software is static or monolithic.

SaaS characteristics

The software is available over the Internet globally through a browser on demand
The typical license is subscription-based or usage-based and is billed on a recurring basis
The software and the service are monitored and maintained by the vendor, regardless of where all the different software components are running
Reduced distribution, maintenance costs and minimal end
user system costs generally make SaaS applications cheaper to use than their shrink-wrapped versions
Such applications feature automated upgrades, updates, and patch management and much faster rollout of changes
SaaS applications often have a much lower barrier to entry than their locally installed competitors, a known recurring cost, and they scale on demand
All users have the same version of the software, so each user's software is compatible with another's
SaaS supports multiple users and provides a shared data model through a single-instance, multi-tenancy model

SaaS - Pros

No large upfront costs - usually free trials
Anywhere, anytime, anyone - mobility
Stay focused on business processes
Change software to an Operating Expense instead of a Capital Purchase, making better accounting and budgeting sense.
Create a consistent application environment for all users
No concerns for cross platform support
Easy Access
Reduced piracy of your software
Lower Cost:

For an affordable monthly subscription;
Implementation fees are significantly lower

Continuous Technology Enhancements

SaaS - Cons

Initial time needed for licensing and agreements

Trust, or the lack thereof, is the number one factor blocking the adoption of software as a service (SaaS).
Centralized control
Possible erosion of customer privacy

Absence of disconnected use
Not suited to high volume data entry
Broadband risk

SaaS ??

Imagine a system

where you don't have to buy new hardware or update software
where you pay nothing or pay as much as you use
where everything is done as a service: Infrastructure, computing, storage and usage
where you don't worry about your resources spent on Infrastructure security and operational security where you cut your IT spending
where you have freedom of usage from anywhere with internet connectivity
which is eco-friendly

Example SaaS applications

Salesforce.com
Google Apps

Gmail, Google Groups, Google Calendar, Talk, Docs, etc
Google Apps Marketplace (Google apps for both free and for a fee)

Microsoft Office 365

Office 365 is a subscription-based online office and software plus services suite which offers access to various services and software built around the Microsoft Office platform

Which applications are suitable?

Any application can be deployed in this way. However communications over the Internet are not as fast as local connections - so leave any high volume data entry applications on your internal LAN or WAN. All the rest can go on the Internet under a SaaS approach.

Myths

SaaS is still relatively new and untested
SaaS is just another version of the failed ASP and hosting models of the past and will suffer the same fate as its predecessors
SaaS only relieves companies of the upfront costs of traditional software licenses
SaaS is only for small and mid-sized businesses and will not be accepted by large-scale organizations
SaaS only applies to applications such as CRM and Salesforce automation
SaaS will only have a minor impact on the software industry and will fade over time
It will be easy for the established software vendors to offer SaaS and dominate this market
SaaS is only for corporate users

Traditional packaged Software Vs SaaS

Traditional packaged Software	Saas
Designed for customers to install, manage and maintain	Designed from the outset up for delivery as Internet-based services
Architect solutions to be run by an individual company in a dedicated instantiation of the software	Designed to run thousands of different customers on a single code
Infrequent, major upgrades every 18-24 months, sold individually to each installed base customer	Frequent, "digestible" upgrades every 3-6 months to minimize customer disruption and enhance satisfaction
Version control	Version control
Upgrade fee	- do -
Fixing a problem for individual customer	Fixing a problem for one customer fixes it for everyone

Monday, 25 April 2022

Export mysqli resultset as excel with nested table in PhP

<?php
error_reporting(E_ERROR | E_WARNING | E_PARSE);
$con = mysqli_connect("localhost", "root", "", "tablename");
if (mysqli_connect_errno()) {
echo "Failed to connect to MySQL: " . mysqli_connect_error();
}
$output = '';
$stmt3 = $con->prepare("SELECT id,registrationid,name,email,mobile,nationality,state,district,gender from adv33");
$stmt3->execute();
$stmt3->bind_result($id, $registrationid, $name, $email, $mobile, $nationality, $state, $district, $gender);
$stmt3->store_result();
if ($stmt3->num_rows > 0) {
$output .= '
<table border="1">
<tr>
<th>Name</th>
<th>Email</th>
<th>Mobile</th>
<th>Nationality</th>
<th>State</th>
<th>District</th>
<th>Gender</th>
</tr>
';
while ($stmt3->fetch()) {
$output .= '
<tr>
<td>' . $name . '</td>
<td>' . $email . '</td>
<td>' . $mobile . '</td>
<td>' . $nationality . '</td>
<td>' . $state . '</td>
<td>' . $district . '</td>
<td>' . $gender . '</td>
</tr>';
$output .= '
<table border="1">
<tr>
<td><b>Post</b></td>
<td><b>Company</b></td>
<td><b>From Date</b></td>
<td><b>To Date</b></td>
<td><b>Scale of Pay</b></td>
';
$stmt4 = $con->prepare("SELECT slno,email,post,company,fromdate,todate,scale FROM adv33exp where email ='$registrationid'");
$stmt4->execute();
/* bind result variables */
$stmt4->bind_result($slno, $email, $post, $company, $fromdate, $todate, $scale);
$stmt4->store_result();
if ($stmt4->num_rows > 0) {
/* fetch value */
while ($stmt4->fetch()) {
$output .= '
<tr>
<td>' . $post . '</td>
<td>' . $company . '</td>
<td>' . $fromdate . '</td>
<td>' . $todate . '</td>
<td>' . $scale . '</td>
</tr>
';
}
}
}
$output .= '</table>';
header("Content-type: application/octet-stream");
header("Content-Disposition: attachment; filename=Applicants.xls");
header("Pragma: no-cache");
header("Expires: 0");
echo $output;
}
?>

Sunday, 24 April 2022

How to get hidden field value in jquery?

JS Code

$(document).ready(function(){

var userid = $('#userid').val();

}

</script>

HTML Code

Saturday, 23 April 2022

Software Development: Iterative and Evolutionary Development

Iterative and Evolutionary Development

Involves early programming and testing of a partial system, in repeating cycles.
Relies on short quick development steps (or iterations), feedback and adaptation to clarify the requirements and design so successively enlarging and refining a system.
Normally assumes that the development starts before all requirements are defined in detail, feedback is used to clarify and improve the evolving specifications.
Each iteration will include requirements, analysis, design, implementation, and test.
Iterative feedback and evolution leads towards the desired system. The requirements and design instability lowers over time.

Current research demonstrates that iterative methods are associated with higher success and productivity rates, and lower defect levels.

Timeboxing

A key idea is that iterations are timeboxed, or fixed in length.

Most iterative methods recommend in iteration length between 2 – 6 weeks.
If it seems that it will be difficult to meet the deadline, the recommended response is to de-scope

De-scoping: removing tasks or requirements from the iteration, and including them in a future iteration, rather than slipping the completion date.

Iterative and Evolutionary Development (also known as iterative and inceremental development; spiral development and evolutionary development)

Build-Feedback-Adapt Cycles

In complex changing systems, feedback and adaptation are key ingredients for success:

Feedback from early development, programmers trying to read specifications, and client demos: to refine the requirements.
Feedback from tests and developers : to refine the design and models.
Feedback from the progress of the team tackling early features : to refine the schedule and estimates.

Benefits of Iterative development

Less project failure, better productivity, and lower defect rates
Early rather than late mitigation of high risks
Early visible progress
Early feedback, user engagement, and adaptation
Managed complexity: the team is not overwhelmed by “analysis paralysis” or very long and complex steps
The learning within an iteration can be methodically used to improve the development process itself, iteration by iteration.

The Unified Process is a popular iterative software development process.

Why a new methodology?

Process-oriented methods:

Requirements of a project are completely frozen before the design and development process commences.
Not always feasible
Need for flexible, adaptable and agile methods, which allow the developers to make late changes in specifications.

Waterfall (Sequential) Lifecycle

Promotes big up-front “speculative” requirements and design steps before programming.
Historically promoted due to belief or hearsay rather than statistically significant evidence.
Success/failure studies show that the waterfall has high failure rates.

Why the waterfall lifecycle fails?

The key false assumption:

The specifications are predictable and stable and can be correctly defined at the start, with low change rates.
But change is a constant on software projects.
A typical software project experienced a 25% change.

Friday, 22 April 2022

Add dynamic rows in html table with Add, Edit, Delete feature in PHP and MySQLi

dynamic-table.php

<!DOCTYPE html>

<head>

<title> Dynamic Table in PhP</title>

</head>

<body>

$(document).ready(function(){

$("#fromdate").datepicker({

changeMonth: true,

changeYear: true,

dateFormat: 'dd/mm/yy'

});

$("#todate").datepicker({

changeMonth: true,

changeYear: true,

dateFormat: 'dd/mm/yy'

});

var employeeData = $('#employeeList').DataTable({

"processing":true,

"serverSide":true,

"bFilter":false,

"bSort" : false ,

"bPaginate": false,

"bInfo" : false,

"order":[],

"ajax":{

url:"action.php",

type:"POST",

data:{action:'listEmployee'},

dataType:"json"

}

});

$('#addEmployee').click(function(){

$('#employeeModal').modal('show');

$('#employeeForm')[0].reset();

$('.modal-title').html("<i class='fa fa-plus'></i> Add Employment Details");

$('#action').val('addEmployee');

$('#save').val('Add');

});

$("#employeeList").on('click', '.update', function(){

var empId = $(this).attr("id");

var action = 'getEmployee';

$.ajax({

url:'action.php',

method:"POST",

data:{empId:empId, action:action},

dataType:"json",

success:function(data){

$('#employeeModal').modal('show');

$('#empId').val(data.id);

$('#post').val(data.post);

$('#company').val(data.company);

$('#type').val(data.type);

$('#fromdate').val(data.fromdate);

$('#todate').val(data.todate);

$('#scale').val(data.scale);

$('#gross').val(data.gross);

$('.modal-title').html("<i class='fa fa-plus'></i> Edit Employee");

$('#action').val('updateEmployee');

$('#save').val('Save');

}

})

});

$("#employeeModal").on('submit','#employeeForm', function(event){

event.preventDefault();

$('#save').attr('disabled','disabled');

var formData = $(this).serialize();

$.ajax({

url:"action.php",

method:"POST",

data:formData,

success:function(data){

$('#employeeForm')[0].reset();

$('#employeeModal').modal('hide');

$('#save').attr('disabled', false);

employeeData.ajax.reload();

}

})

});

$("#employeeList").on('click', '.delete', function(){

var empId = $(this).attr("id");

var action = "empDelete";

if(confirm("Are you sure you want to delete this employee?")) {

$.ajax({

url:"action.php",

method:"POST",

data:{empId:empId, action:action},

success:function(data) {

employeeData.ajax.reload();

}

})

} else {

return false;

}

});

</script>

</div>

</div>

<thead>

<tr>

<th>Department/ Institute/ Company</th>

<th>Permanent/ Temporary/ Contract</th>

<th>Scale of pay</th>

<th>Gross Amount</th>

</tr>

</table>

</div>

<h4 class="modal-title"><i class="fa fa-plus"></i> Edit Employment Details</h4>

</div>

<div class="form-group"

</div>

<label for="company" class="control-label">Department/ Institute/ Company</label>

</div>

<label for="type" class="control-label">Permanent/ Temporary/ Contract</label>

</div>

</div>

</div>

<label for="scale" class="control-label">Scale of pay</label>

</div>

<label for="gross" class="control-label">Gross Amount</label>

</div>

<button type="button" class="btn btn-default" data-dismiss="modal">Close</button>

</div>

</form>

</div>

</div>

</div>

</div>

action.php

<?php

include('Employee.php');

$emp = new Employee();

if(!empty($_POST['action']) && $_POST['action'] == 'listEmployee') {

$emp->employeeList();

}

if(!empty($_POST['action']) && $_POST['action'] == 'addEmployee') {

$emp->addEmployee();

}

if(!empty($_POST['action']) && $_POST['action'] == 'getEmployee') {

$emp->getEmployee();

}

if(!empty($_POST['action']) && $_POST['action'] == 'updateEmployee') {

$emp->updateEmployee();

}

if(!empty($_POST['action']) && $_POST['action'] == 'empDelete') {

$emp->deleteEmployee();

}

Config.php

<?php
class dbConfig {
protected $serverName;
protected $userName;
protected $password;
protected $dbName;
function dbConfig() {
$this -> serverName = 'localhost';
$this -> userName = 'root';
$this -> password = "";
$this -> dbName = "employee";
}
}
?>

Employee.php

<?php require('config.php'); class Employee extends Dbconfig { protected $hostName; protected $userName; protected $password; protected $dbName; private $empTable = 'employment'; private $dbConnect = false; public function __construct(){ if(!$this->dbConnect){ $database = new dbConfig(); $this -> hostName = $database -> serverName; $this -> userName = $database -> userName; $this -> password = $database ->password; $this -> dbName = $database -> dbName; $conn = new mysqli($this->hostName, $this->userName, $this->password, $this->dbName); if($conn->connect_error){ die("Error failed to connect to MySQL: " . $conn->connect_error); } else{ $this->dbConnect = $conn; } } } public function employeeList(){ $sqlQuery = "SELECT * FROM ".$this->empTable." "; $result = mysqli_query($this->dbConnect, $sqlQuery); $employeeData = array(); while( $employee = mysqli_fetch_assoc($result) ) { $empRows = array(); $empRows[] = $employee['post']; $empRows[] = $employee['company']; $empRows[] = $employee['type']; $empRows[] = $employee['fromdate']; $empRows[] = $employee['todate']; $empRows[] = $employee['scale']; $empRows[] = $employee['gross']; $empRows[] = '<button type="button" name="update" id="'.$employee["id"].'" class="btn btn-warning btn-xs update">Update</button>'; $empRows[] = '<button type="button" name="delete" id="'.$employee["id"].'" class="btn btn-danger btn-xs delete" >Delete</button>'; $employeeData[] = $empRows; } $output = array( "draw" => intval($_POST["draw"]), "data" => $employeeData ); echo json_encode($output); } public function getEmployee(){ if($_POST["empId"]) { $sqlQuery = " SELECT * FROM ".$this->empTable." WHERE id = '".$_POST["empId"]."'"; $result = mysqli_query($this->dbConnect, $sqlQuery); $row = mysqli_fetch_array($result, MYSQLI_ASSOC); echo json_encode($row); } } public function updateEmployee(){ if($_POST['empId']) { $updateQuery = "UPDATE ".$this->empTable." SET userid = '".$_POST["userid"]."', post = '".$_POST["post"]."', company = '".$_POST["company"]."', type = '".$_POST["type"]."', fromdate = '".$_POST["fromdate"]."' , todate = '".$_POST["todate"]."' , scale = '".$_POST["scale"]."', gross = '".$_POST["gross"]."' WHERE id ='".$_POST["empId"]."'"; $isUpdated = mysqli_query($this->dbConnect, $updateQuery); } } public function addEmployee(){ $insertQuery = "INSERT INTO ".$this->empTable." (userid, post, company, type, fromdate, todate,scale, gross) VALUES ('".$_POST["userid"]."','".$_POST["post"]."', '".$_POST["company"]."', '".$_POST["type"]."', '".$_POST["fromdate"]."', '".$_POST["todate"]."', '".$_POST["scale"]."', '".$_POST["gross"]."')"; $isUpdated = mysqli_query($this->dbConnect, $insertQuery); } public function deleteEmployee(){ if($_POST["empId"]) { $sqlDelete = " DELETE FROM ".$this->empTable." WHERE id = '".$_POST["empId"]."'"; mysqli_query($this->dbConnect, $sqlDelete); } } } ?>

employee.sql

CREATE TABLE `employment` (

`id` int(10) NOT NULL,

`userid` int(10) DEFAULT NULL,

`post` varchar(100) DEFAULT NULL,

`company` varchar(100) DEFAULT NULL,

`type` varchar(25) DEFAULT NULL,

`fromdate` varchar(25) DEFAULT NULL,

`todate` varchar(25) DEFAULT NULL,

`scale` varchar(50) DEFAULT NULL,

`gross` varchar(50) DEFAULT NULL

) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4;

Thursday, 21 April 2022

Unified Process (UP) Best Practices

Get high risk and high value requirements first
Constant user feedback and engagement
Early cohesive core architecture
Test early, often, and realistically
Apply use cases where needed
Do some visual modeling with UML
Manage requirements and scope creep
Manage change requests and configuration

How to persist the selected value of the select box after form submit?

<?php
if ($_POST['submit']) {
if ($_POST['srf'] != "") {
$srf = $_POST['srf'];
} else {
$srfErr = "This field is required.";
}
}
?>
<form method="post">
<select name="srf" id="srf" class="form-control">
<option value="">Select</option>
<option <?php if (isset($srf) && $srf=="1") echo "selected";?>>1</option>
<option <?php if (isset($srf) && $srf=="2") echo "selected";?>>2</option>
<option <?php if (isset($srf) && $srf=="3") echo "selected";?>>3</option>
</select> <?php if($srfErr!= ""){ ?>
<p><b><?php echo $srfErr; ?></b></p>
</div>
<?php }?>
<input type="submit" name="submit" value="submit" />
</form>