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PowerShell FundamentalsBY PAWEL MOZDZEN

PowerShell Fundamentals 2

PowerShell ISE

DEMOFinalProduct.ps1

FinalProductRun.ps1

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What we will cover Custom Objects

Advanced Parameters

Steps for Building a Proper Function

Help System

Pipeline

Scope

But not.. PowerShell Syntax Specific SharePoint Cmdlets

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Help System Update-Help Get-Help

Get-Help Parameters- Full- Examples- Detailed- Online- ShowWindow

Get-Member

Examples

1. Get-Help Get-SPSite –Full

2. Get-Help Get-SP*

3. Get-Help Get-SPSite –Parameter Limit

Examples

1. Get-SPSite | Get-Member

2. Get-SPSite | Select Url, Owner | Get-Member

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PowerShell ISE

DEMOHelp.ps1

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Understanding Help SyntaxGet-Help New-SPSiteSyntax

New-SPSite [-AdministrationSiteType <None | TenantAdministration>] [-AssignmentCollection <SPAssignmentCollection>] [-CompatibilityLevel <Int32>] [-Confirm <SwitchParameter>] [-ContentDatabase <SPContentDatabasePipeBind>] [-Description <String>] [-HostHeaderWebApplication <SPWebApplicationPipeBind>] [-Language <UInt32>] [-Name <String>] [-OverrideCompatibilityRestriction <SwitchParameter>] [-OwnerEmail <String>] [-QuotaTemplate <SPQuotaTemplatePipeBind>] [-SecondaryEmail <String>] [-SecondaryOwnerAlias <SPUserPipeBind>] [-SiteSubscription <SPSiteSubscriptionPipeBind>] [-Template <SPWebTemplatePipeBind>] [-WhatIf <SwitchParameter>]

[-Url] <String>[-Url] <String> -OwnerAlias <SPUserPipeBind>-OwnerAlias <SPUserPipeBind>

[<CommonParameters>][<CommonParameters>]

Get-Help New-SPUser …[-PermissionLevel <String[]>] …..

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Pipeline

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Pipeline - the Old Way

Command I

StdOut StdIn StdErr

Command II

StdOut StdIn StdErr

Text

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Working with Pipeline – PowerShell Way

Command I

Output Errors Warnings

Command II

-Param

OBJECTVerbose Debug

-Param-Param 1

-Param-Param-Param

…n

? Pipeline Parameter Binding By Value By Property Name

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Pipeline

DEMOPipeByValue.ps1

PipeByPropertyName.ps1

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ScopeGlobal Scope - Runspace Global Scope - Runspace

Function Scope

Script Scope

Function Scope

Script Scope

Script ScopeFunction Scope

Compartmentalization of Scope

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General Rules Scoped elements exist only in scope they were created. Accessing non-existent element will result in reaching out to the parent scope. Scoped elements can be created with the same name as in the parent scope. When a scope is finished processing it is destroyed and removed from memory.

Dot Sourcing

Private variables

Strict Mode Set-StrictMode -Off Set-StrictMode -Version [1,2,3,latest]

Scope

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Scope

DEMOScopeRunScript.ps1

ScopeTempScript.ps1

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Benefits for turning script into a function Once loaded into memory it is available for later use: Dot-Sourcing, Import-Module Function has its own scope Multiple functions per script file. Provides better separation of concerns for complex tasks.

Function Example function Get-SiteColumnStats{ $spWeb = Get-spweb "http://sps-demo:5555/sites/acct" $spFields = $spWeb.Fields $spFields | Group-Object TypeAsString | Sort-Object Count -Descending}Get-SiteColumnStats

Functions

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Everything in PowerShell is an OBJECT

Functions and scripts can return only one kind of thing.

Use Custom Objects to consolidate information before returning it.

To return a collection of data assign it to a property of the custom object.

Techniques for creating custom objects: Using Hashtable Using Select-Object Using Add-Member Using Type Declaration

Custom Objects

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Custom Objects – Creation Techniques

DEMOCustomObjects.ps1

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Custom Objects - Real Life Example

DEMOExport-Audiences.ps1

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Functions – Advanced Parameters

Get-Help about_Functions_Advanced_Paramenters

All PowerShell functions follow a verb dash noun naming standard.

Adds certain features to a function:• Enables [Parameter()] decorator,• Adds standard set of extra function

parameters such us –verbose, -debug

Makes parameter required. Any default values will be ignored. Enables to accept values from pipeline. Accepts values of the same type. Only one such decorator for the same type.

Enables to accept values from pipeline. Accepts values from passed in object’s

properties same name. First it will try to find a match By Value then

by Property Name

BEGIN and END blocks execute only once. PROCESS block executes for each piped in

object

Important to handle function calls where values are passed in via parameter.

Redundant if piped in.

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Advanced Parameters - Real Life Example

DEMOExport-Audiences.ps1

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Defined as set of parameter decorators. Each validator defined as a separate decorator.

[ValidateCount(1,50)]

[ValidateLength(1,50)]

[ValidateScript({...})]

[ValidateSet[("One","Two","Three")]

[ValidatePattern("\w+\\\w+")]

[ValidateRange(1,5)]

Parameter Validation

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Validate against null or empty values:

[ValidateNotNull()]

[ValidateNotNullOrEmpty()]

For mandatory parameters to allow null values:

[AllowNull()]

[AllowEmptyString()]

[AllowEmptyCollection()]

Parameter Validation – Cont’d.

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Parameter Validation - Example

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Verbose Output: Write-VerboseA way to check variables’ state in longer scriptsA way to comment script behavior documenting itA way to notify about longer running processesAnd the most important..

Debug Output: Write-DebugTo let you know which line is currently processingTo pause the execution and let user check things

Verbose and Debug Output

a way to avoid using Write-Host

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Converting script to a module

Accessing Module Use: Import-Module moduleFileName.psm1 Place module in PowerShell searchable locations: $env:PSModulePath

Special considerations for saving modules in PowerShell locations: Always save your module within a folder of the same name. Use letters and numbers only.

Exporting Module Members Export-ModuleMember -Function <functionName>

Export-ModuleMember -Variable <variableName> Example: Export-ModuleMember -Function *-*

Functions in Script Modules

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Start with defining a task. Build base command(s). Turn it into a function. Parameterize it. Test it calling in different ways. Add error handling if necessary. Add Verbose and Debug output. Turn it into a module.

Steps for Building a Proper Function

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Steps for Building a Proper Function

DEMOFunctionBuildingSteps.ps1

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