Reporting on expired recurring meetings with EWS and Powershell

Someone asked an interesting question about recurring Appointments in Exchange recently that I thought I'd expand on a bit with blog post. Recurrence in Appointments,Meeting and Tasks are one of the more useful features of Exchange, but they are also one the features that are harder for developers and anybody writing code or scripts to get a handle on. These days there is some really good technical documentation on this so I won't explain too much but firstly http://msdn.microsoft.com/EN-US/library/office/dn727655(v=exchg.150).aspx but also the Exchange Protocol Document http://msdn.microsoft.com/en-us/library/ee201188(v=exchg.80).aspx are a must to read.

To refine this down a bit with Calendar Appointments if you have a recurring Appointment you don't have separate objects for each occurrence of the recurring Appointment, the recurrence is just a pattern stored in a property on what is called the master instance of that particular Appointment, Meeting or Task. Exception information is stored as part of the Recurrence pattern (while the actual data from the Exception if there is anything different from the Master instance eg say you add an attachment to an exception this data gets stored as AttachedItem on the Master instance).

What this all means is that when it comes time to actually query the Calendar Appointments these recurrence patterns need to be expanded. To do this in EWS you use the CalendarView class and you specify a Start and End Date for your query. Exchange will then do all the hard work for you and return the expanded Appointments (and exceptions) to you.

To get back to the actual question however of how you would find expired recurring Calendar Appointments you have to forget about making an expansion query and instead you want to make a query to return a list of these master instances of recurring calendar Appointments and then filter these at the client side to work out what has expired (or if you want to do other reporting like seeing who has made non expiring appointments you can do this).

So to do this you can use the FindItem operation with a restriction on the PidLidRecurring property http://msdn.microsoft.com/en-us/library/ee157994(v=EXCHG.80).aspx which looks like this

1. $Recurring = new-object Microsoft.Exchange.WebServices.Data.ExtendedPropertyDefinition([Microsoft.Exchange.WebServices.Data.DefaultExtendedPropertySet]::Appointment, 0x8223,[Microsoft.Exchange.WebServices.Data.MapiPropertyType]::Boolean);   
2.   
3. $sfItemSearchFilter = new-object Microsoft.Exchange.WebServices.Data.SearchFilter+IsEqualTo($Recurring,$true)   

This will then return a list of Master Appointment instances, to get the full details of the Recurrence of each appointment you need to do a GetItem on each of the master instance which in the Managed API you can use the LoadPropertiesForItems method for. This will make a batch GetItem request to the Exchange Server to return the detail on all Items your request it for.

Once you have the recurrence information you can then filter those Meetings that have an End Date (or Recurrence number) set by using the HasEnd property.  Then to check the Last Occurrence you can use the LastOccurrence property. If you want to report on other things like meetings that don't have an EndDate or meetings that are expiring in the next week or month this is where you can put your own customization.

The following script will produce a report of any expired Meetings in a Mailbox's calendar and save this to a CSV file. I've put a download of this script here the code itself looks like

1. ## Get the Mailbox to Access from the 1st commandline argument  
2.   
3. $MailboxName = $args[0]  
4.   
5. ## Load Managed API dll    
6. Add-Type -Path "C:\Program Files\Microsoft\Exchange\Web Services\2.1\Microsoft.Exchange.WebServices.dll"    
7.     
8. ## Set Exchange Version    
9. $ExchangeVersion = [Microsoft.Exchange.WebServices.Data.ExchangeVersion]::Exchange2010_SP2    
10.     
11. ## Create Exchange Service Object    
12. $service = New-Object Microsoft.Exchange.WebServices.Data.ExchangeService($ExchangeVersion)    
13.     
14. ## Set Credentials to use two options are availible Option1 to use explict credentials or Option 2 use the Default (logged On) credentials    
15.     
16. #Credentials Option 1 using UPN for the windows Account    
17. $psCred = Get-Credential    
18. $creds = New-Object System.Net.NetworkCredential($psCred.UserName.ToString(),$psCred.GetNetworkCredential().password.ToString())    
19. $service.Credentials = $creds        
20.     
21. #Credentials Option 2    
22. #service.UseDefaultCredentials = $true    
23.     
24. ## Choose to ignore any SSL Warning issues caused by Self Signed Certificates    
25.     
26. ## Code From http://poshcode.org/624  
27. ## Create a compilation environment  
28. $Provider=New-Object Microsoft.CSharp.CSharpCodeProvider  
29. $Compiler=$Provider.CreateCompiler()  
30. $Params=New-Object System.CodeDom.Compiler.CompilerParameters  
31. $Params.GenerateExecutable=$False  
32. $Params.GenerateInMemory=$True  
33. $Params.IncludeDebugInformation=$False  
34. $Params.ReferencedAssemblies.Add("System.DLL") | Out-Null  
35.   
36. $TASource=@' 
37.   namespace Local.ToolkitExtensions.Net.CertificatePolicy{ 
38.     public class TrustAll : System.Net.ICertificatePolicy { 
39.       public TrustAll() {  
40.       } 
41.       public bool CheckValidationResult(System.Net.ServicePoint sp, 
42.         System.Security.Cryptography.X509Certificates.X509Certificate cert,  
43.         System.Net.WebRequest req, int problem) { 
44.         return true; 
45.       } 
46.     } 
47.   } 
48. '@   
49. $TAResults=$Provider.CompileAssemblyFromSource($Params,$TASource)  
50. $TAAssembly=$TAResults.CompiledAssembly  
51.   
52. ## We now create an instance of the TrustAll and attach it to the ServicePointManager  
53. $TrustAll=$TAAssembly.CreateInstance("Local.ToolkitExtensions.Net.CertificatePolicy.TrustAll")  
54. [System.Net.ServicePointManager]::CertificatePolicy=$TrustAll  
55.   
56. ## end code from http://poshcode.org/624  
57.     
58. ## Set the URL of the CAS (Client Access Server) to use two options are availbe to use Autodiscover to find the CAS URL or Hardcode the CAS to use    
59.     
60. #CAS URL Option 1 Autodiscover    
61. $service.AutodiscoverUrl($MailboxName,{$true})    
62. "Using CAS Server : " + $Service.url     
63.      
64. #CAS URL Option 2 Hardcoded    
65.     
66. #$uri=[system.URI] "https://casservername/ews/exchange.asmx"    
67. #$service.Url = $uri      
68.     
69. ## Optional section for Exchange Impersonation    
70.     
71. #$service.ImpersonatedUserId = new-object Microsoft.Exchange.WebServices.Data.ImpersonatedUserId([Microsoft.Exchange.WebServices.Data.ConnectingIdType]::SmtpAddress, $MailboxName)   
72.   
73. # Bind to the Calendar Folder  
74. $folderid= new-object Microsoft.Exchange.WebServices.Data.FolderId([Microsoft.Exchange.WebServices.Data.WellKnownFolderName]::Calendar,$MailboxName)     
75. $Calendar = [Microsoft.Exchange.WebServices.Data.Folder]::Bind($service,$folderid)  
76.   
77. $Recurring = new-object Microsoft.Exchange.WebServices.Data.ExtendedPropertyDefinition([Microsoft.Exchange.WebServices.Data.DefaultExtendedPropertySet]::Appointment, 0x8223,[Microsoft.Exchange.WebServices.Data.MapiPropertyType]::Boolean);   
78.   
79. $sfItemSearchFilter = new-object Microsoft.Exchange.WebServices.Data.SearchFilter+IsEqualTo($Recurring,$true)   
80.   
81.   
82. #Define ItemView to retrive just 1000 Items      
83. $ivItemView =  New-Object Microsoft.Exchange.WebServices.Data.ItemView(1000)     
84. $rptCollection = @()  
85. $fiItems = $null      
86. do{   
87.     $psPropset= new-object Microsoft.Exchange.WebServices.Data.PropertySet([Microsoft.Exchange.WebServices.Data.BasePropertySet]::FirstClassProperties)    
88.     $fiItems = $service.FindItems($Calendar.Id,$sfItemSearchFilter,$ivItemView)     
89.     if($fiItems.Items.Count -gt 0){  
90.         [Void]$service.LoadPropertiesForItems($fiItems,$psPropset)    
91.         foreach($Item in $fiItems.Items){   
92.             if($Item.Recurrence.HasEnd){  
93.                 if($Item.LastOccurrence.End -lt (Get-Date)){  
94.                     $rptObj = "" | Select Mailbox,Organizer,AppointmentSubject,FirstOccuranceStart,FirstOccuranceEnd,LastOccuranceStart,LastOccuranceEnd  
95.                     Write-Host "Appointment : "  $Item.Subject  
96.                     Write-Host "Last Occurance : " $Item.LastOccurrence.Start  
97.                     $rptObj.Mailbox = $MailboxName  
98.                     $rptObj.Organizer = $Item.Organizer.Name  
99.                     $rptObj.AppointmentSubject = $Item.Subject  
100.                     $rptObj.FirstOccuranceStart = $Item.FirstOccurrence.Start  
101.                     $rptObj.FirstOccuranceEnd = $Item.FirstOccurrence.End  
102.                     $rptObj.LastOccuranceStart = $Item.LastOccurrence.Start  
103.                     $rptObj.LastOccuranceEnd = $Item.LastOccurrence.End               
104.                     $rptCollection += $rptObj  
105.                 }  
106.             }  
107.         }  
108.     }  
109.     $ivItemView.Offset += $fiItems.Items.Count      
110. }while($fiItems.MoreAvailable -eq $true)   
111. $rptCollection | Export-Csv -NoTypeInformation -Path c:\Temp\$MailboxName-ExpiredRecurringMeetings.csv  
112. Write-Host "Report written to " c:\Temp\$MailboxName-ExpiredRecurringMeetings.csv