Powershell, invoke-webrequest...and Zabbix

I'm trying to use powershell to automate the creation of a reporting tool. I need to get Zabbix (v1.8) graph images. As it is not yet possible through the API I must connect to the URL and then get the graphs.

This is my code :

$zabbixLoginUrl = "http://zabfront-eqx.noc.lan/zabbix/index.php?login=1"
$zabbixGraphUrl = "http://zabfront-eqx.noc.lan/zabbix/chart2.php?graphid="
$userName = "username"
$userPwd = "pwd"

$loginPostData = @{name=$userName;password=$userPwd;enter="Enter"}
$login = Invoke-WebRequest -Uri $zabbixLoginUrl -Method Post -Body $loginPostData -SessionVariable sessionZabbix

#let's see if we have a cookie set
if ($sessionZabbix.Cookies.Count -eq 0) {
    Write-Host "fail to connect"
    break
}
else {Write-Host "connected"}


#now let's retrieve the graph #4433 using the priviously established session
$graph = Invoke-WebRequest -Uri ($zabbixGraphUrl+"4433") -WebSession $sessionZabbix

I can connect and get a cookie :

$sessionZabbix.Cookies.GetCookies("http://zabfront-eqx.noc.lan/zabbix/index.php") | select name, value

    Name                                                                                Value                                                                              
    ----                                                                                -----                                                                              
    zbx_sessionid                                                                       b2451e6c7fd0767dec22cca46427b7c2

Unfortunatly $graph contains no "image" property and the "content" idicates that I'm not connected :

$graph.Images.Count
0

$graph.Content
[...]
<span class="footer_sign">Not connected</span>

Anyone knows what I've done wrong??

Thanks

Solution

SO I got it to work : I needed to set a cookie for the graph URL using the same sessionid :

$sessionZabbix.Cookies.SetCookies("http://zabfront-eqx.noc.lan/zabbix/chart2.php", $sessionZabbix.Cookies.GetCookieHeader($zabbixLoginUrl))