Read your Microsoft Teams messages using Microsoft Graph and Powershell

 I suck at time cards. Part of it is that I'm jumping between 30 tasks at once - help this team, help that team, training, documentation, and my sprint work. At the end of the day I have a bare-ass notebook with a few cryptic lines about what I did today - if I'm lucky.  

But a lot of it is available elsewhere. We're all virtual now, so all my interactions are either voice calls, meetings, or chats.  I want to list out what I did in a given day so I can reconstruct it - how much time I spent helping whom.

Enter Microsoft Graph. It's an API that selects from it. There's a set of cmdlets that let you do quite a bit.  I really do wish the get-mgchatmessagedelta properly handled "-filter" to make this faster, but I'll cope.

This will rip through ALL your chats, then for each one get the most recent 200 messages, filter it down to the past day or two, then toss it out on a format-table. 

My pain, your gain.  It's always fun when there's 2 google results for something. 

Install-Module Microsoft.Graph
Import-Module Microsoft.Graph.Teams
$RequiredScopes = @("Chat.ReadBasic", "Chat.ReadWrite")
Connect-MgGraph -Scopes $RequiredScopes
#at this point a browser window should appear - allow it.
#I had to find my user id in graph explorer UI by running GET   V1.0    https://graph.microsoft.com/v1.0/me
#unsure how to get it otherwise - but you don't need it with get-mgchat
get-mgchat
#take one of those IDs
#let's look at this chat:
get-mgchat  -ChatId 19:deadbeefb2d949d88d4455f5279e5d8b@thread.v2
get-mgchatmessage -ChatId 19:deadbeefb2d949d88d4455f5279e5d8b@thread.v2 

#this nests and walks through properly, strips HTML, but lord this will be slow.  And shows more than one line per message, even when I try now to.
#By default you can get all your chats by running get-mgchat.  -all and -pagesize 50 is required for the module to paginate the request and get you everything. But in my case it grabbed all 2000 chats. The -first 5 is for testing.
$tzone = Get-TimeZone  # conversion from GMT to local time. https://jdhitsolutions.com/blog/powershell/7962/convert-to-local-time-with-powershell/
$mychats = get-mgchat -all -PageSize 50  |select -first 5
$all_chat_info = @() #force-setting to an array
$all_chat_info = foreach ($chat in $mychats) { 
    $chatinfo = get-mgchat -ChatId $chat.id #get base details about the CHAT itself
    #set some details about the chat itself for the later query
    $chatname = $chat.Topic
    $members = $chat.Members
    $chattype = $chat.chattype
    #now get every message from that chat since midnight yesterday.  Note LastModifiedDateTime is GMT.    The jdhit page says -($tzone...), but all I had to do was .tolocaltime() ... I think.
    #the -top 200 -pagesize 50 is to get the most recent 200 messages, and again you have to paginate.   
    $recentchatmessages = get-mgchatmessage -ChatId $chat.id -top 200 -pagesize 50 |where {$_.LastModifiedDateTime.tolocaltime() -gt (get-date).date.AddDays(-1)} # all from after midnight yesterday |select -first 5
    #and now use select expression to add the above fields and parse the below fields, stripping out HTML (but I can't seem to only get the first line in OGV)
    $recentchatmessages | select @{Label='LastModified';Expression={($_.LastModifiedDateTime.tolocaltime())}}, @{Label='ChatName';Expression={($chatname)}}, @{Label='members';Expression={($members)}}, @{Label='ChatType';Expression={($chattype)}}, 
    @{Label='From';Expression={($_.from.user.displayname)}}, @{Label='Body';Expression={ ($_.Body.content -split '\n')[0] -replace '<[^>]+>',''}}
    #@{Label='From';Expression={($_.from.user.displayname)}}, @{Label='Body';Expression={( ($_.Body.content -replace '<[^>]+>','').split([Environment]::NewLine)|select -first 1)}}
}
$all_chat_info|format-table 
#and now close/disconnect
Disconnect-MgGraph