How to Update the Modified By and Created By fields using PnP - powershell

Question

I'm trying to upload a fileshare from my local machine to SharePoint using Add-PnPFile, i also have csv that has all the properties("Modified By", "Created By") for each file.
I have written this code below to grab the all the properties of the files from a csv document and tested to see if the user existed in the tenant before the using the Add-PnPFile command to upload the file.
Function Upload-Nom{
Param (
[parameter(Position=0,ValueFromPipeline=$True,ValueFromPipelineByPropertyName=$True)]
[Alias('FullName')]
[string[]]$Path = $PWD
)
Begin {}
Process {
ForEach ($item in $Path) {
#iterate all the file urls in the csv
Import-Csv $item | ForEach-Object {
#capture all the properties you need to update the file properties on sharepoint
$name = $_.Name
$fullName = $_.FullName
$itemtype = $_.'Item Type'
$relativepath = $_.Path -replace '(sites\/honours\/)'
$modifiedbyuser = $_.'Modified By'
$createdbyuser = $_.'Created By'
$modified = $_.Modified
$path = $_.Path -replace '\/','\'
$path = $path -replace '(sites\\honours\\)'
$fullurl ="C:\Users\modonny\Downloads\" +$path+"\"+ $name
#convert dates to SP format
[DateTime]$dateformats = New-Object System.DateTime;
if([DateTime]::TryParse($_.Modified, [ref]$dateformats)){
$cdob = $dateformats;
}
$modifieduser = Get-PnPUser | ? Title -eq $modifiedbyuser
$createduser = Get-PnPUser | ? Title -eq $createdbyuser
#check if user exists in tenancy
if($modifieduser){
$muserid = $modifiedbyuser.Email
}else{
$muserid = "john.doe#test.gov.uk"
}
if($createduser){
$cuserid = $createduser.Email
}else{
$createduser = Get-PnPUser | ? Email -EQ "john.doe#test.gov.uk"
$cuserid = "john.doe#test.gov.uk"
}
$object = #{}
$object.Add("Modified",$cdob)
$object.Add("Editor" ,$muserid)
$object.Add("Author" ,$cuserid)
if($fullurl | Test-Path){
if($itemtype -eq 'Folder'){
write-host "this item is a folder"
}else{
#upload files to sharepoint with the data in the $object variable
Add-PnPFile -Path $fullurl -Folder $relativepath -Values $object
}
}
}
}
}
Upload-Nom -Path "C:\Users\modonny\Documents\testing.csv"
When the code completes running all files are uploaded but the Modified By/Created By property isn't.

Answer 1

Sample script for your reference.
#region Variables
$Username = "user#tenant.onmicrosoft.com"
$Password = "password"
$siteURL = "https://tenant.sharepoint.com/sites/Community"
#endregion Variables
#region Credentials
[SecureString]$SecurePass = ConvertTo-SecureString $Password -AsPlainText -Force
[System.Management.Automation.PSCredential]$PSCredentials = New-Object System.Management.Automation.PSCredential($Username, $SecurePass)
#endregion Credentials
Connect-PnPOnline -Url $siteURL -Credentials $PSCredentials
$user=Get-PnPUser | ? Email -eq "user1#tenant.onmicrosoft.com"
Add-PnPFile -Path "C:\Lee\test.docx" -Folder "MyDoc" -Values #{Editor=""+$user.Id+"";Modified="7/24/2019"}