SharePoint On Premise : Script to fetch the list of users having access to a SiteCollection, groups they are part of and subsites having access to

 Below scirpt will help you to pull the above mentioned inventory from SharePoint site collection quickly to a CSV file.

#Load required dlls
if ((Get-PSSnapin
"Microsoft.SharePoint.PowerShell" -ErrorAction SilentlyContinue) -eq
$null) { 
  Add-PSSnapin"Microsoft.SharePoint.PowerShell" 
} 
 

#File references.
$csvClientsPath = $PSScriptRoot+"\ClientDetails.csv";

 
$dateTime = $(Get-Date -format u)-replace ':','_' ;
$logPath = $PSScriptRoot +'\ExportedUsers_'+$dateTime+'.csv' -replace '\s',''

 
#Result
$global:UserDataCollection = @();

  
function LogMessages()
{
param($clientId,$clientURL,$userLogin,$userDisplayName,$userEmail, $UserProjects,
$userGroupString)

 
 $UserData = New-Object PSObject;

$UserData| Add-Member -type NoteProperty -name "ClientId" -value $clientId;        
$UserData| Add-Member -type NoteProperty -name "ClientURL" -value $clientURL;                        
$UserData| Add-Member -type NoteProperty -name "UserLogin" -value $userLogin;
$UserData| Add-Member -type NoteProperty -name "DisplayName" -value $userDisplayName;
$UserData| Add-Member -type NoteProperty -name "EmailID" -value $userEmail;
$UserData| Add-Member -type NoteProperty -name "Projects" -value $UserProjects; 
$UserData| Add-Member -type NoteProperty -name "Groups" -value $userGroupString; 

$global:UserDataCollection += $UserData;                                                                                     

Write-Host $(Get-Date -format g) $UserData -ForegroundColor Yellow -backgroundcolor Blue;
}

 
function Import-UsersFromClient()

{
  Import-Csv -Path $csvClientsPath |%{
  #Loop CSV to get client ID and Client URL.

    $web=$null;
    $site=$null;
    try{
      if($_.ClientURL)
      {

      if([bool] ($site = Get-SPSite $_.ClientURL -ErrorAction SilentlyContinue) -eq $true) {      

      $web = $site.rootweb;

      if($web)
      {

       $allUsers= $web.siteUsers;
        #Loop thourgh all the users and pull the required information.

        foreach($currUser in $allUsers)

        {
          $userGroups;
          $userSites;

          try{          
 
          $currSiteCollection= $null;
          $rootWeb= $null;

          try{
           #Get the list of all the SharePoint Groups user is part of.

          $userGroups = $currUser| select @{Name='Groups';Expression={$_.Groups -join '|'}}

          #Get the list of subsites user has access to.

          $token = $currUser.UserToken;

          $currSiteCollection = new-object microsoft.sharepoint.spsite($_.ClientURL, $token);

          $rootWeb = $currSiteCollection.RootWeb;                

          $accessWeb = $rootWeb.GetSubwebsForCurrentUser();

          if($accessWeb.count-gt 0)
          {               
          $userSites= $accessWeb.WebsInfo.ToArray().ServerRelativeUrl -join '|';
          }  
           
           LogMessages -clientId $_.ClientId -clientURL $_.ClientURL -userLogin $currUser.UserLogin.ToString()
-userDisplayName $currUser.displayName.ToString() -userEmail
$currUser.Email.ToString() -UserProjects $userSites -userGroupString $userGroups.Groups.ToString()
          }

          catch{
          LogMessages -clientId $clientId -clientURL $_.ClientURL -userLogin
$currUser.UserLogin.ToString()
-userDisplayName $currUser.displayName.ToString() -userEmail
$_.Exception.Message -UserProjects $_.Exception.Message -userGroupString
$_.Exception.Message

          }

          finally
          {
          if($rootWeb)
          {
          $rootWeb.Dispose();
          }

          if($currSiteCollection)
          {
          $currSiteCollection.Dispose();
          }
          }
        }
          catch{
LogMessages -clientId $clientId -clientURL $_.ClientURL -userLogin
$_.Exception.Message -userDisplayName $_.Exception.Message -userEmail
$_.Exception.Message -UserProjects $_.Exception.Message -userGroupString
$_.Exception.Message

        }
        }
      }
      }
      }
     }

    catch{
    LogMessages -clientId $_.Exception.Message -clientURL $_.Exception.Message -userLogin
$_.Exception.Message -userDisplayName $_.Exception.Message -userEmail
$_.Exception.Message -UserProjects $_.Exception.Message -userGroupString
$_.Exception.Message
    }
    finally
    {
     if($web){
     $web.Dispose();
     } 
     if($site){
     $site.Dispose();

     }
    }
}
} 

#Call Method
Import-UsersFromClient;

#Store Data To CSV.
$UserDataCollection | Export-Csv-LiteralPath $logPath -NoTypeInformation