Saturday, November 28, 2009

Basic Powershell script to show appointments from a calendar using the EWS Managed API

One of the more common tasks you might turn to use one of the Exchange API's for is to enumerate appointments in one or more users calendars. This can be useful for a number of reasons and applications and scripts, the EWS Managed API makes getting calendar appointment pretty easy using a script once you understand a few of the fundamentals around how calendar appointment's are stored.

Appointments unlike messages are more complex objects eg where an email would only represent one object in a folder an appointment if its recurring or a recurring exception or a deleted occurrence could represent one more calendar appointments. So its important not just to do a finditems query like you would with Email messages as this will return just the base instances of each appointment object. What you should do when querying for calendar appointments is its important to use a CalendarView, what this means is that when you query for appointments you specify a date range (start and end) for the appointments you what to retrieve and EWS will handle expanding any recurring appointments,deleted occurrences etc and return you what is essentially what you would see in Outlook (which does the same thing). This is a rather simplified explanation if you want to read more check out this sample chapter from Inside Exchange Web Services which is available on MSDN.

So when it comes to putting all this together in Powershell script that will pull all the appointments from a specific calendar we first need to specify the SMTP address of a mailbox you want to access and a Date range you want to check in a few variables

$MailboxName = ""
$StartDate = new-object System.DateTime(2009, 08, 01)
$EndDate = new-object System.DateTime(2009, 11, 01)

or maybe you want to look at the appointment for next week

$StartDate = new-object [System.DateTime]::Now
$EndDate = new-object [System.DateTime]::Now.AddDays(7)

Connect to EWS using the currently logged on Credentials the assumes that this account has access to the mailbox is question.

$dllpath = "C:\Program Files\Microsoft\Exchange\Web Services\1.0\Microsoft.Exchange.WebServices.dll"
$service = New-Object Microsoft.Exchange.WebServices.Data.ExchangeService([Microsoft.Exchange.WebServices.Data.ExchangeVersion]::Exchange2007_SP1)

$windowsIdentity = [System.Security.Principal.WindowsIdentity]::GetCurrent()
$sidbind = "LDAP://<SID=" + $windowsIdentity.user.Value.ToString() + ">"
$aceuser = [ADSI]$sidbind


Then you need to specify the calendarview object to use

$folderid = new-object Microsoft.Exchange.WebServices.Data.FolderId([Microsoft.Exchange.WebServices.Data.WellKnownFolderName]::Calendar,$MailboxName)
$CalendarFolder = [Microsoft.Exchange.WebServices.Data.CalendarFolder]::Bind($service,$folderid)
$cvCalendarview = new-object Microsoft.Exchange.WebServices.Data.CalendarView($StartDate,$EndDate,2000)

and finally query the calendar and return the appointments

$cvCalendarview.PropertySet = new-object Microsoft.Exchange.WebServices.Data.PropertySet([Microsoft.Exchange.WebServices.Data.BasePropertySet]::FirstClassProperties)
$frCalendarResult = $CalendarFolder.FindAppointments($cvCalendarview)
foreach ($apApointment in $frCalendarResult.Items){
$psPropset = new-object Microsoft.Exchange.WebServices.Data.PropertySet([Microsoft.Exchange.WebServices.Data.BasePropertySet]::FirstClassProperties)
"Appointment : " + $apApointment.Subject.ToString()
"Start : " + $apApointment.Start.ToString()
"End : " + $apApointment.End.ToString()
"Organizer : " + $apApointment.Organizer.ToString()
"Required Attendees :"
foreach($attendee in $apApointment.RequiredAttendees){
" " + $attendee.Address
"Optional Attendees :"
foreach($attendee in $apApointment.OptionalAttendees){
" " + $attendee.Address
"Resources :"
foreach($attendee in $apApointment.Resources){
" " + $attendee.Address
" "

I've put a download of the script here.


Oliver Marshall said...

What would need to be changed to allow this script to work with a list of mailboxes, rather than just one specific mailbox ?

Goldmember said...

I cant get to work with exchange2010

It fails when i try to bind the $service and $folderId

Jeffrey Patton said...

Hi, Not sure when Goldmember's comment was made, but here is my code. I skipped binding to the user object as it appeared all you were doing in the orignal snippet was grabbing their email address. As I'm using this for myself, I just used the MailboxName var declared earlier.

$MailboxName = ''
$StartDate = Get-Date
$EndDate = (Get-Date).AddDays(7)
$DllPath = 'C:\Program Files\Microsoft\Exchange\Web Services\1.2\Microsoft.Exchange.WebServices.dll'
$Service = New-Object Microsoft.Exchange.WebServices.Data.ExchangeService([Microsoft.Exchange.WebServices.Data.ExchangeVersion]::Exchange2010)
$FolderID = New-Object Microsoft.Exchange.WebServices.Data.FolderId([Microsoft.Exchange.WebServices.Data.WellKnownFolderName]::Calendar,$MailboxName)
$CalendarFolder = [Microsoft.Exchange.WebServices.Data.CalendarFolder]::Bind($Service,$FolderID)
$Calendarview.PropertySet = New-Object Microsoft.Exchange.WebServices.Data.PropertySet([Microsoft.Exchange.WebServices.Data.BasePropertySet]::FirstClassProperties)
$CalendarResult = $CalendarFolder.FindAppointments($CalendarView)

foreach ($Appointment in $CalendarResult.Items)
$Propset = New-Object Microsoft.Exchange.WebServices.Data.PropertySet([Microsoft.Exchange.WebServices.Data.BasePropertySet]::FirstClassProperties)
New-Object -TypeName PSObject -Property @{
Appointment = $Appointment.Subject.ToString()
Start = $Appointment.Start.ToString()
End = $Appointment.End.ToString()
Organizer = $Appointment.Organizer.ToString()

Jeff Girotto said...

I've having a hard time viewing the LastOccurrence property in a RecurringMaster. I always get null. Also, for extended properties, I normally need to load them into the property set, but I can't find the tag for this property. Any ideas?

Simon Berg said...

Anyone know how to get the category color from the appointment?

Simon Berg said...

Hi Jeff

Thats my problem to. I dont know how to load the ExtendedProperties. I believe what i'm looking for is in that Collection...