Update-CosmosDocument.ps1

function Update-CosmosDocument {
    <#
    .SYNOPSIS
    Updates a specific Cosmos Document
    
    .DESCRIPTION
    Updates a specific Cosmos Document
    
    .PARAMETER DatabaseName
    Name of the Database containing the Collection containing the document you want to update
    
    .PARAMETER CollectionName
    Name of the Collection containing the document you want to update
    
    .PARAMETER DocumentId
    The DocumentId of the document you want to update
    
    .PARAMETER Document
    A hashtable containing the new Document
    
    .PARAMETER CosmosDBVariables
    This is the Script variable generated by Connect-CosmosDB - no need to supply this variable, unless you get really creative
    
    .EXAMPLE
    $NewData = @{
        GivenName = 'Eternal'
        Surname = 'Suffering'
    }
    Update-CosmosDocument -DatabaseName MyPrivateCosmos -CollectionName Chaos -DocumentId "c3210778-0ac2-4bc8-b0dd-d465192bf2c8" -Document $NewData
    
    .NOTES
    https://docs.microsoft.com/en-us/rest/api/documentdb/replace-a-document
    #>
    [CmdletBinding()]
    param (
        [Parameter(Mandatory=$true,
        HelpMessage='Name of the Database containing the Document')]
        [string]$DatabaseName,
        [Parameter(Mandatory=$true,
        HelpMessage='Name of the Collection containing the Document')]
        [string]$CollectionName,
        [Parameter(Mandatory=$true,
        HelpMessage='Id of the Document')]
        [string]$DocumentId,
        [Parameter(Mandatory=$true,
        HelpMessage='The document formatted as a hashtable')]
        [hashtable]$Document,
        [Parameter(Mandatory=$false,
        HelpMessage="Use Connect-CosmosDB to create this Variable collection")]
        [hashtable]$CosmosDBVariables=$Script:CosmosDBVariables
    )
    
    begin {
        Test-CosmosDBVariable $CosmosDBVariables
        $Database = $Script:CosmosDBConnection[($DatabaseName + '_db')]
        if (-not $Database) {
            Write-Warning "$DatabaseName not found"
            continue
        }
        $Collection = $Script:CosmosDBConnection[$DatabaseName][$CollectionName]
        if (-not $Collection) {
            Write-Warning "$CollectionName not found"
            continue
        }
    }
    
    process {
        $CurrentDocument = Get-CosmosDocument -DatabaseName $DatabaseName -CollectionName $CollectionName -DocumentId $DocumentId
        if (-not $CurrentDocument) {
            Write-Warning "Document $DocumentID not found in collection $CollectionName in database $DatabaseName"
            continue
        }
        $Verb = 'PUT'
        $Url = '{0}/{1}' -f $CosmosDBVariables['URI'],$CurrentDocument._self
        $ResourceType = 'docs'
        $Header = New-CosmosDBHeader -resourceId $CurrentDocument._rid -resourceType $ResourceType -Verb $Verb
        if ($Document.Keys -notcontains 'id'){
            $Document['id'] = $DocumentID
            Write-Verbose "Adding id: $DocumentID to Document body"
        }
        $CosmosBody = $Document | ConvertTo-Json
        try {
            $Return = Invoke-RestMethod -Uri $Url -Headers $Header -Method $Verb -Body $CosmosBody -ErrorAction Stop
            Write-Verbose "$($Document['id']) has been updated in $CollectionName"
        }
        catch {
            Write-Warning -Message $_.Exception.Message
        }
    }
    
    end {
    }
}