RingCentral Send Fax

# https://forums.developers.ringcentral.com/questions/9012/sending-a-fax-attachment-using-powershell.html

$todestination = [pscustomobject]@()
$todestination += @{
    phoneNumber = "+14435551212"
    name = "Test Recipient"
}

### CONVERT FILE CONTENT TO BASE64 STRING
$FilePath = "$($env:TEMP)\TestFax.PDF"
$objFile = Get-ItemProperty -Path $FilePath
$FileData = [Convert]::ToBase64String([IO.File]::ReadAllBytes($FilePath))

$RingCentralSendFaxJson = [pscustomobject]@{}
Add-Member -InputObject $RingCentralSendFaxJson -MemberType NoteProperty -Name to -Value $todestination
Add-Member -InputObject $RingCentralSendFaxJson -MemberType NoteProperty -Name faxResolution -Value "High"

$RingCentralSendFaxJson = $RingCentralSendFaxJson | ConvertTo-Json

$LF = "`r`n";
$boundary = "Boundry_$([System.Guid]::NewGuid().ToString();)"

# Need to package the message body in multipart/mixed format
$RingCentralSendFax = (
    "--$($boundary)",
    "Content-Type: application/json",
    "",
    $RingCentralSendFaxJson,
    "",
    "--$($boundary)",
    "Content-Disposition: form-data; name=""attachment""; filename=""$($objFile.Name)""",
    "Content-Transfer-Encoding: binary",
    "Content-Type: application/octet-stream",
    "",
    "$FileData",
    "",

    "--$($boundary)--"
) -join $LF

$accountId = "~"
$extensionId = "~"

#Send the text message
$sendresponse = Invoke-RestMethod -Uri "https://platform.devtest.ringcentral.com/restapi/v1.0/account/$($accountId)/extension/$($extensionId)/fax" -Method Post -ContentType "multipart/mixed; boundary=$($boundary)" -Body $RingCentralSendFax -Headers $accesstoken.Header