Step 1: Load the Web.config File

Firstly, you will need to load the Web.config file into PowerShell. You can accomplish this using the XmlDocument class.

[xml]$webConfig = Get-Content 'C:\path\to\web.config'

Step 2: Navigate to the appSettings Section

Once the Web.config file is loaded, navigate to the appSettings section to access the key-value pairs. Utilize the SelectNodes method to get all the add elements under the appSettings section.

$appSettings = $webConfig.Configuration.appSettings.add

Step 3: Create an Array to Store Key-Value Pairs

Before iterating through the appSettings, create an array to store the key-value pairs.

$keyValuePairs = @()

Step 4: Extract Key-Value Pairs

Iterate over each added element, create a customized PowerShell object for each key-value pair, and add each object to the array.

foreach ($setting in $appSettings) {
    $obj = New-Object PSObject
    $obj | Add-Member -MemberType NoteProperty -Name "Key" -Value $setting.Key
    $obj | Add-Member -MemberType NoteProperty -Name "Value" -Value $setting.Value
    $keyValuePairs += $obj
}

Step 5: Export Key-Value Pairs to a CSV File

Finally, use the Export-Csv cmdlet to write the key-value pairs to a CSV file.

$keyValuePairs | Export-Csv -Path 'C:\path\to\output.csv' -NoTypeInformation

Using PowerShell, you can extract appSettings from a Web.config file and export them to a CSV file with just a few lines of code. This approach provides a straightforward way to manage and analyze your application configurations. The script can be further customized or wrapped into a reusable function, making it a versatile tool for configuration management in .NET applications.

The post Exporting Web.config AppSettings to CSV using PowerShell appeared first on TEKSpace Blog.

Unlike the traditional command-line interface (CLI) like the Command Prompt, PowerShell’s flexibility comes from its ability to work with objects and data streams. By utilizing cmdlets, users can perform operations on data objects directly, making it easier to manipulate and manage information. Moreover, PowerShell offers the capability to create and execute scripts, enabling users to automate intricate processes and repetitive tasks efficiently.

However, before harnessing the full potential of PowerShell commands and scripts, one must navigate the concept of execution policies. These policies dictate the level of trust PowerShell places in various scripts and configurations. Understanding and managing these policies ensures a secure and controlled environment for executing scripts and commands. Whether it’s for automating routine tasks, managing systems at scale, or extracting insights from data, Windows PowerShell serves as an indispensable platform that empowers users to achieve efficient and streamlined operations within the Windows environment.

Here are the top 100 PowerShell commands to use and everyone should master:

The post Top 100 Essential PowerShell Commands: Your Must-Know Cheat Sheet appeared first on TEKSpace Blog.

To make life easier, I have checked my PowerShell code on Github. Feel free to download them and modify them to your needs.

In this tutorial, I will go over how to get resource groups from Azure REST API. One of the basic CRUD operations, I will perform.

Create a file called Get-AzureResourceGroup.ps1. Let’s create the required variables. Make sure to fill in the required variables from your Azure subscription.

Variables

# Variables
$TenantId = "" # Enter Tenant Id.
$ClientId = "" # Enter Client Id.
$ClientSecret = "" # Enter Client Secret.
$Resource = "https://management.core.windows.net/"
$SubscriptionId = "" # Enter Subscription Id.

Once you have updated the above required values. Let’s make a first REST call to get access token.

We will use the below URL to make a REST call to get access token.

POST https://login.microsoftonline.com/{tenantId}/oauth2/token

Request Access Token

Add the following code to your PowerShell script after variables.

$RequestAccessTokenUri = "https://login.microsoftonline.com/$TenantId/oauth2/token"

$body = "grant_type=client_credentials&client_id=$ClientId&client_secret=$ClientSecret&resource=$Resource"

$Token = Invoke-RestMethod -Method Post -Uri $RequestAccessTokenUri -Body $body -ContentType 'application/x-www-form-urlencoded'

Write-Host "Print Token" -ForegroundColor Green
Write-Output $Token

After you have retrieved the access token, we will use that to authorize Azure REST methods.

Get Resource groups

To retrieve all resource groups in Azure. We will use the below URL.

GET https://management.azure.com/subscriptions/{subscriptionId}/resourcegroups?api-version=2017-05-10

Enter below code to Get-AzureResourceGroup.ps1.

# Get Azure Resource Groups
$ResourceGroupApiUri = "https://management.azure.com/subscriptions/$SubscriptionId/resourcegroups?api-version=2017-05-10"

$Headers = @{}

$Headers.Add("Authorization","$($Token.token_type) "+ " " + "$($Token.access_token)")

$ResourceGroups = Invoke-RestMethod -Method Get -Uri $ResourceGroupApiUri -Headers $Headers

Write-Host "Print Resource groups" -ForegroundColor Green
Write-Output $ResourceGroups

The above line of code should return all the resource groups from an Azure subscription.

Below is the full script and output.

# Variables
$TenantId = "" # Enter Tenant Id.
$ClientId = "" # Enter Client Id.
$ClientSecret = "" # Enter Client Secret.
$Resource = "https://management.core.windows.net/"
$SubscriptionId = "" # Enter Subscription Id.

$RequestAccessTokenUri = "https://login.microsoftonline.com/$TenantId/oauth2/token"

$body = "grant_type=client_credentials&client_id=$ClientId&client_secret=$ClientSecret&resource=$Resource"

$Token = Invoke-RestMethod -Method Post -Uri $RequestAccessTokenUri -Body $body -ContentType 'application/x-www-form-urlencoded'

Write-Host "Print Token" -ForegroundColor Green
Write-Output $Token

# Get Azure Resource Groups
$ResourceGroupApiUri = "https://management.azure.com/subscriptions/$SubscriptionId/resourcegroups?api-version=2017-05-10"

$Headers = @{}

$Headers.Add("Authorization","$($Token.token_type) "+ " " + "$($Token.access_token)")

$ResourceGroups = Invoke-RestMethod -Method Get -Uri $ResourceGroupApiUri -Headers $Headers

Write-Host "Print Resource groups" -ForegroundColor Green
Write-Output $ResourceGroups

Output:

The post Access Azure REST API using PowerShell appeared first on TEKSpace Blog.

In this tutorial, I will show you how to convert a certificate from .pfx to base64.

Open PowerShell as an administrator.

Now that we have a PowerShell console opened. Let’s first load the content into a variable.

$pfx_cert = get-content 'c:\certificate.pfx' -Encoding Byte

The above command will load the content with byte encoding. If you print $pfx_cert in the PowerShell console, you will see random numbers. In order to convert to base64 format, we will use system namespace from Windows system.

To convert a certificate in base64, execute the below command.

$base64 = [System.Convert]::ToBase64String($pfx_cert)

The above command will save it in $base64 variable, and now you can use this variable or output it to a file depending on your scenario.

The post Convert certificate from pfx to base64 with PowerShell appeared first on TEKSpace Blog.

I will be using PowerShell to listen for new changes. You can use any scripting / programing language you like. I chose PowerShell because I would like to manage my Kubernetes Cluster via the Windows system.

Before I get into details, I recommend following this articles on

• How to setup Kubernetes Cluster in Ubuntu 16.04
• How to manage Kubernetes Cluster remotely using windows 10.
• Remote Access Permissions.

Understanding Kubernetes API

Kubernetes API provides access to Kubernetes Cluster to manage Pods, Services, and much more. You can get more details from Kubernetes Reference Documentation.. One of the challenge I had was finding right examples on above reference doc from kubernetes site. But I was able to manage to understand how the API worked using Kubernetes Dashboard and using Fiddler to monitor calls made my Kubernetes Dashboard.

If you followed my articles from above. You will see that accessing API via Kubectl proxy makes it much more easier. You can then write your code in any language and make request to proxy URL that already has all the authentication and access mechanism created for you. So you don’t have to add that in your code.

In this tutorial, I will use a proxy URL to make API calls. You can choose any method you like by referring to Kubernetes Documentation.

From your remote machine where you have kubectl and kube config file setup, execute below command to proxy your API requests.

kubectl proxy

The above link will provide you a proxy URL that then you can use in your script to watch for events. You should receive something similar as shown below.

Starting to serve on 127.0.0.1:8001

The default API URL is http://127.0.0.1:8001/api/v1. Depending on when you are reading this blog, the API version may change. You can get the API version from http://127.0.0.1:8001/ and then you can use that in your code.

Now that you know how to access API. Let’s go deep on how make a get request to watch for changes in services API.

Accessing Services API

Services API can be accessed by making a GET request to http://127.0.0.1:8001/api/v1/services. This will give you all the available services as JSON.

There is also a watch API where you can make GET request, which will keep the connection open as long as your proxy is up and running. You can make the request at http://127.0.0.1:8001/api/v1/watch/services. This will return all the events that are created in all the namespaces. If you want to make a get request on a specific namespace, you can use /api/v1/watch/namespaces/{namespace}/services/{name} and change values that are in {}. I will use /api/v1/watch/services to watch for events for all the namespaces and then filter out on what I need.

I have created a repository on Git that contains PowerShell script that will watch for new events. You can download it and make appropriate changes for your environments from here.

The script contains following logic that will run in while loop and perform action accordingly.

#regions HTTP Watch Request
$request = [System.Net.WebRequest]::Create($watch_services_url)
# Get Response
$resp = $request.GetResponse()
# Get Response Stream
$reqstream = $resp.GetResponseStream()
# Create new object for StreamReader
$sr = New-Object System.IO.StreamReader $reqstream
# Create a loop for listening for new events
while (!$sr.EndOfStream)
{
    # Read the line
    $line = $sr.ReadLine();
    # Convert json string to PSObject
    $line_object = $line | ConvertFrom-Json
    # Get Metadata
    $metadata = $line_object.object.metadata
    # Get request type
    $type = $line_object.type

    # Process data returned
    Process-Request -object $line_object
}
# Function
function Process-Request
{
    Param
    (
        [psobject]$object
    )
    $data = $object
    $data = Remove-Old-Events -object $data
    if ($data.type -eq "ADDED")
    {
        # Create Load balancer
        $metadata = Create-LB-Metadata -object $data
        Create-LoadBalancer -object $metadata
    }
    if ($data.type -eq "DELETED")
    {
        # Delete Load balancer
        # Add logic here

    }
    if ($data.type -eq "MODIFIED")
    {
        # Modify Load balancer 
        # Add logic here

    }
}
#endregions

The above while loop example will run until it reaches the end of the stream. The watch request that we made to Kubernetes API, will continuously run and connection will stay open between client and master node for infinitely unless there is a network disconnect or master node is unreachable. You will have to write your own logic to add retry function in case you have lost access to API.

In the script, I left Create-LoadBalancer & Delete-LoadBalancer empty. You can insert your own business logic to create proxy or virtual IP via your external load balancer.

This tutorial is created to understand how API works for watch events and does not go very deep to it. As long as you understand how the integration to API works, you should be able to add your own custom logic depending on your environment.

The post Kubernetes Services Watch For New Events appeared first on TEKSpace Blog.