SDT scheduling using REST API and PowerShell

Updated version of the script. I think I will stop here

# Usage via command line
#
# LogicMonitor-Add-SDTs.ps1 -maintenance_date "12/03/2018" -maintenance_time "01:00:00" -maintenance_length 30 -type "serviceGroupSDT" -id 14
#
# Usage via CSV import:

# $csv = Import-Csv file.csv
# foreach ($line in $csv) {
#       LogicMonitor-Add-SDTs.ps1 -maintenance_date $line.date -maintenance_time $line.time -maintenance_length $line.length -type $line.type -id $line.id
# }
#
# the CSV file needs to have the following header and content type
# Date,Time,Length,Type,ID
# 
 
  Param(
                [Parameter(Mandatory=$True)]
                [string]$maintenance_date,
                [Parameter(Mandatory=$True)]
                [string]$maintenance_time,
                [Parameter(Mandatory=$True)]
                [int]$maintenance_length,
                [Parameter(Mandatory=$True)]
                [string]$type,
                [Parameter(Mandatory=$True)]
                [int]$id,
                [switch]$force = $false
                )

<# account info #>
$accessId = 'IDHERE'
$accessKey = 'KEYHERE'
$company = 'api'

# stdTYpe (integer)
# 1 - one time, 2 - Weekly SDT, 3 - Monthly SDT, 4 - Daily SDT
# we have to use "one time" style values because LM has no concept of day of month
$stdTYpe = 1


# dataSourceId (integer)
# 0 = ALL
$dataSourceId = 0

<# request details #>
$httpVerb = 'POST'
$resourcePath = '/sdt/sdts'

$startDate = (Get-Date -Date "$maintenance_date $maintenance_time").ToUniversalTime()
$startDateepoch = [Math]::Round((New-TimeSpan -start (Get-Date -Date "1/1/1970") -end $startDate).TotalMilliseconds)

$endDate = $startDate.AddMinutes($maintenance_length)
$endDateepoch = [Math]::Round((New-TimeSpan -start (Get-Date -Date "1/1/1970") -end $endDate).TotalMilliseconds)

# data
switch ($type)

    {
     "DeviceGroupSDT" {$data = '{"sdtType":'+$stdTYpe+',"type":"'+ $type +'","deviceGroupId":'+ $Id +',"dataSourceId":'+ $dataSourceId +',"startDateTime":'+ $startDateepoch +',"endDateTime":'+ $endDateepoch +'}'}
     "ServiceGroupSDT" {$data = '{"sdtType":1,"type":"ServiceGroupSDT","serviceGroupId":14,"startDateTime":'+ $startDateepoch +',"endDateTime":'+ $endDateepoch +'}'}
     "CollectorSDT" {$data = '{"sdtType":'+$stdTYpe+',"type":"'+ $type +'","collectorId":'+ $Id +',"startDateTime":'+ $startDateepoch +',"endDateTime":'+ $endDateepoch +'}'}
     default {$data = ""}
    }

<# Construct URL #>
$url = 'https://' + $company + '.logicmonitor.com/santaba/rest' + $resourcePath

<# Get current time in milliseconds #>
$epoch = [Math]::Round((New-TimeSpan -start (Get-Date -Date "1/1/1970") -end (Get-Date).ToUniversalTime()).TotalMilliseconds)

<# Concatenate Request Details #>
$requestVars = $httpVerb + $epoch + $data + $resourcePath

<# Construct Signature #>
$hmac = New-Object System.Security.Cryptography.HMACSHA256
$hmac.Key = [Text.Encoding]::UTF8.GetBytes($accessKey)
$signatureBytes = $hmac.ComputeHash([Text.Encoding]::UTF8.GetBytes($requestVars))
$signatureHex = [System.BitConverter]::ToString($signatureBytes) -replace '-'
$signature = [System.Convert]::ToBase64String([System.Text.Encoding]::UTF8.GetBytes($signatureHex.ToLower()))

<# Construct Headers #>
$auth = 'LMv1 ' + $accessId + ':' + $signature + ':' + $epoch
$headers = New-Object "System.Collections.Generic.Dictionary[[String],[String]]"
$headers.Add("Authorization",$auth)
$headers.Add("Content-Type",'application/json')

<# Make Request #>
$response = Invoke-RestMethod -Uri $url -Method $httpVerb -Body $data -Header $headers

<# Print status and body of response #>
$status = $response.status
$body = $response.data| ConvertTo-Json -Depth 5

# Write-Host "Query:$data"
Write-Host "Status:$status"
Write-Host "Response:$body"