Hanif

Tuesday, November 19, 2019

AWS Solutions Architect Associate Concepts- Networking & Content Delivery

Networking & Content Delivery

CloudFront

Edge location
Origin
Distribution

Web
RTMP

Objects are cashed for life TTL (Time to Live)
Edge locations are not read-only
There is a cost associated with cleanup the cache

AWS Solutions Architect Associate Concepts, S3

Storage

S3 - Simple Storage Service

S3 is object bases storage to upload files (0-5TB file size)
It is unlimited storage
In S3 files are stored in globally unique buckets
It is a storage service so not suitable for any sort of installation e.g Operating System.
Turn on MFA Delete - Multi-factor Delete used to avoid accidental deletion of files/ object from S3
S3 Fundamental

ID, Value, Version, Metadata
Sub-resources

Access control list
Torrent

Read after write consistency
Eventual Consistency
S3 Classes/Tiers

S3 Standard
S3 - IA (Infrequent Access) - Charge on the basis of access
S3 One Zone - IA
S3 Intelligent Tiering
S3 Glacier (Retrieval Time: Minutes to Hours)
S3 Glacier Deep Archive ( Retrieval Time: 12 Hours)

https://aws.amazon.com/s3/faqs/

S3 Encryptions

Encryption in Transit (SSL/TSL)
Encryption at Rest / Server-Side Encryption

SSE-S3
SSE-KMS
SSR-C

Client-Side Encryption

S3 Version

Stores all version of an object
Versioning can be suspended not disable after enabling it
MFA Delete can be an extra protection layer for object deletion

S3 Life Cycle Management
S3 Cross-Region Replication
S3 Transfer Accelerator

https://s3-accelerate-speedtest.s3-accelerate.amazonaws.com/en/accelerate-speed-comparsion.html

Storage Gateway

File Gateway
Volume Gateway

Stored Volumes
Cached Volumes

Gateway Virtual Tape Library

Saturday, November 16, 2019

AWS Solutions Architect Associate - Concepts

Security, Identity, and Compliance

IAM Service - Identity Access Management Service

Users
Groups
Policies
Roles
MFA - Multi-Factor Authentication
Google Authentication
Root user

Management and Governance

Cloud Watch

Billing Alarm

Friday, February 19, 2016

AngularJS Services

The service is a javascript object or a function available to the application. We can use services to wrap the common functionality for the application.

There are my built-in services in Angular JS like $http, $interval, $location etc.

We can define our own services depending on requirements.

<body>

<p>Result : {{result}}</p>

</div>

var app = angular.module('myApp', []);

app.service('myCalc', function() {

this.multiply = function (x,y) {

return x*y;

}

this.add = function (x,y) {

return x+y;

}

});

app.controller('myCtrl', function($scope, myCalc) {

$scope.result= myCalc.add(5,4);

});

</script>

</body>

AngularJS Filters ( | )

Filters are used to transform the data in desired formats. Angular provides many builtin filters (json, orderby, uppercase,currency,date and filter etc.) and we can define our own filters as well depending on requirements.

Filters can be used to an expression by using '|' followed by the filter.

<body>

<div ng-app="myApp" ng-controller="formatCtrl">
Amount : {{ amount | currency }}
</div>

<script>
var app = angular.module('myApp', []);
app.controller('formatCtrl', function($scope) {
$scope.amount = 14523.2;
});
</script>

</body>

AngularJS Scope ($scope)

Scope is bridge between Html(View) and controller in Angular JS applications. It is a java script object holding properties and method for view and controller.

The scoped defined at application level is called $rootScope and is available in entire application.

If we two variable with same names in root scope and current scope then current scope variable will get precedence.

<!DOCTYPE html>
<html>
<script src="http://ajax.googleapis.com/ajax/libs/angularjs/1.4.8/angular.min.js"></script>

<body ng-app="myApp">

RootScope : {{myVar}}

<div ng-controller="myCtrl">

Controller Scope : {{myVar}}

</div>

<script>

var app = angular.module('myApp', []);
app.run(function($rootScope) {
$rootScope.myVar = 'In Root Scope';
});
app.controller('myCtrl', function($scope) {
$scope.myVar = "In current contrller scope";
});

</script>

</body>
</html>

Thursday, February 18, 2016

AngularJS Controllers (ng-controller)

It controls the application data. It is a regular javascript object created by object constructor.
It wraps up all logic for UI manipulation and is a bridge between client side and server side/third party API's etc.

It stores the application data and performs operations on it depending on requirements.

<div ng-app="myApp" ng-controller="myController">
First Name: <input type="text" ng-model="firstName"><br>
Last Name: <input type="text" ng-model="lastName"><br>
<br>
Full Name: {{fullName()}}
</div>

<script>
var app = angular.module('myApp', []);
app.controller('myController', function($scope) {
$scope.firstName = "";
$scope.lastName = "";
$scope.fullName = function() {
return $scope.firstName + " " + $scope.lastName;
};
});
</script>

Angular Model

The ng-model directive binds the HTML control value to the application data. This is a two way binding if we change value in control it will automatically get changed in the app data and vice versa.

AngularJS will create property implicitly if it is missing in ng-model attribute.

In order to check status of the application data like valid, modified or touched, ng-model provides a power support.

Following classes are being added ore removed depending on status of the model.

ng-valid
ng-invalid
ng-pending
ng-pristine
ng-touched
ng-untouched
ng-dirty

<form ng-app="" name="testForm">
Email Address :<input type="email" name="emailAddress" ng-model="myText" required>
<p>Valid: {{testForm.emailAddress.$valid}} </p>
<p>Touched: {{testForm.emailAddress.$touched}} </p>
<p>Dirty: {{testForm.emailAddress.$dirty}} </p>
</form>

AngularJS Directives

Directives provide AngularJS core functionality of extending HTML with new attributes.

There are a lot of built-in directives to support diverse functionality to the applications.

e.g.

ng-app directive initializes an AngularJS application.
ng-init directive initializes application data.
ng-model directive binds the HTML controls to application data.

We can also define our own directives depending on requirements.

<!DOCTYPE html>

<html>

<my-btn-submit></my-btn-submit>

var app = angular.module("myApp", []);

app.directive("myBtnSubmit", function() {

return {

restrict : "C",

template : "<input type='submit' value='Submit'></input>"

};

});

</script>

</body>

</html>

We can restrict directive invocation with 'restrict' values are:

E - Invoke as Element name

A - Can be used as Attribute

C - Can be use as Class

By default the value is EA, means can be invoked both as, an Element name and attribute name.

AngularJS Modules

AngularJS
module defines the application. Which wraps up all different components of the
application like controllers, directives etc. The controllers always belong to
a module.

<div ng-app="myApp">...</div>

<script>

var app = angular.module("myApp", []);

</script>

AngularJS Expressions

AngularJS Expressions are used to bind data to HTML and can be written in side double curly braces {{2+2}} and in can also be written in directives like ng-bind=”2+2”.

<div ng-app="">
<p> Angular Expression: {{ 10 + 20 }}</p>
</div>

AngularJS Expressions are very similar to JavaScript Expressions but there are some differences.

Both support literals, operators, and variables.
Angular expressions support filters, while JavaScript expressions do not.
Angular expressions can be written inside HTML but we can not write JavaScript expressions inside HTML.
JavaScript expressions support conditionals, loops, and exceptions, while Angular expressions do not support this.

What is difference between angular expression {{}} and ‘ng-bind’ and which is better?

The expression {{}} binds data to HTML same like ng-bind directive. But ng-bind is better approach than {{}}. Followings are few of the considerations.

Key difference is {{ }} can flash on page load while ‘ng-bind’ hides the expression until it is displayed correctly.
The Angular JS registers a watcher for the variable being used in ng-bind.
The ‘ng-bind’ stores only value of the variable in memory.

<!DOCTYPE html>
<html>
<script src="http://ajax.googleapis.com/ajax/libs/angularjs/1.4.8/angular.min.js"></script>
<body>

<div ng-app="" data-ng-init="var1=5;var2=7">

<p>Result = <span data-ng-bind="var1+var2"></span></p>
<div>Result = {{(var1+var2)}}</div>

</div>

</body>
</html>

Initializing multiple variables in ‘ng-init’ for AngularJS application

<!DOCTYPE html>
<html>
<script src="http://ajax.googleapis.com/ajax/libs/angularjs/1.4.8/angular.min.js"></script>
<body>

<div ng-app="" data-ng-init="var1=5;var2=7; varStr='Hello'">
<p> <span data-ng-bind="varStr"></span></p>
<p> var1 = <span data-ng-bind="var1"></span></p>
<p>var2 = <span data-ng-bind="var2"></span></p>
<div>var1+var2 = {{(4+5)}}</div>

</div>

</body>
</html>

Friday, August 22, 2014

How to Enable Code Preview Scroll Bar in VS 2013.

Tuesday, August 12, 2014

How to Enable/Disable JavaScript In Chrome?

Tuesday, July 15, 2014

Creating nth level menu by recursion

Private Sub AppendChildToMenuStrip(ByRef DropDownItems As ToolStripItemCollection, _
ByVal Tag As String, _
ByVal Title As String, _
ByVal ParentIDAs Integer)

For Each Item As Object In DropDownItems

Dim SubMenu As ToolStripMenuItem = TryCast(Item, ToolStripMenuItem)

If SubMenu.Tag = ParentID Then

Dim ToolStripItem As New ToolStripMenuItem

ToolStripItem.Tag = Tag : ToolStripItem.Text = Title

SubMenu.DropDownItems.Add(ToolStripItem)

ElseIf SubMenu.HasDropDownItems Then

AppendChildToMenuStrip(SubMenu.DropDownItems, Tag, Title, ParentID)

End If

Next

End Sub

Using MS Script control to Evaluate Arithmetic Expressions

The MS Script Control COM component provide simple way to evaluate arithmetic expressions like below.

(2*3)/3

2+3-4

(3*4)+(4+6)/4*5

Add reference of MS Script Control COM component in the project

Following is the sample code to evaluate it.

Public Function EvaluateExpression(ByVal expression As String) As Double

Dim ScriptControl As New MSScriptControl.ScriptControl

ScriptControl.Language = "VBSCRIPT"
Return Convert.ToDouble(ScriptControl.Eval(expression))

End Function

Wednesday, June 5, 2013

Integrating “jqxGrid” in ASP.NET C# Application

Download Code Sample

I explored the JqxGrid on last weekend, and found it a very powerful tool for data representation on client side.

Find the attached code sample with main features filtering like Sorting, Paging and Filtering.
Use link below to see useful demos of “jqxGrid” and some other powerful plugins provide by jQWidgets.

http://www.jqwidgets.com/jquery-widgets-demo/demos/jqxgrid/index.htm?(web)

Thursday, April 4, 2013

How to register 32 bit DLL to 64 bit in Win 7?

Use following simple steps to register 32 bit Dll in 64bit operating system.

1. Copy MyDll.dll to “c:\windows\sysWOW64\”
2. Run command prompt as administrator
3. Reach to "sysWOS64" directory by “cd c:\windows\sysWOW64\” command
4. Run “regsvr32 MyDll.dll” in command prompt

Wednesday, March 27, 2013

The calling thread must be STA, because many UI components require this. in WPF.

I faced this issue while opening my window in WPF application. After spending some hour on Google found I got this work around.

[STAThread]

public void ShowPopuWindow()

{

try

{

Thread _Worker = new Thread(DisplayIncommingCallPopup);

_Worker.SetApartmentState(ApartmentState.STA);

_Worker.Start();

_Worker.Join();

}

catch (Exception ex) {MessageBox.Show(ex.Message);}

}

public void DisplayIncommingCallPopup()

{

try

{

CallPopupWindow callPopupWindow = new CallPopupWindow();

callPopupWindow.ShowDialog();

}

catch (Exception ex) { MessageBox.Show(ex.Message); }

}