How to handle server address not resolved in XMLHTTP request? - vbscript

Question

I used the following code to check if a RSS url responds in 5 seconds so I can consume the RSS feed however trying to open the URL causes error when the target URL could not be resolved. What more I need rather than waitForResponse to also handle this situation?
Set http = Server.CreateObject("MSXML2.ServerXMLHTTP")
http.open "POST", "https://persiadigest.com/fa/rss/8", True
http.send
If http.waitForResponse(5) Then
body=http.responsetext
Else
response.write "Target url is not responding"
End If
Set http = Nothing
Error details:
msxml3.dll error '80072ee7' The server name or address could not be
resolved

Answer 1

Give a try for this example and tell me the results :
Option Explicit
Dim Title : Title = "Get RSS FEED"
Dim ArrURL : ArrURL = Array("https://persiadigest.com/fa/rss/8","http://khabarfoori.com/rss/mm")
Dim URL
For Each URL in ArrURL
If CheckURL(URL) = "200" Then
MsgBox chr(34) & URL & chr(34) & " ==> is active"& vbCrLF &_
"Status : " & CheckURL(URL),vbInformation,Title
MsgBox GetDataFromURL(URL,"GET",""),vbInformation,Title
Else
MsgBox chr(34) & URL & chr(34) & " ==> is inactive" & vbCrLF &_
"Status : " & CheckURL(URL),vbCritical,Title
End if
Next
'---------------------------------------------------------------------------
Function GetDataFromURL(strURL, strMethod, strPostData)
Dim lngTimeout
Dim strUserAgentString
Dim intSslErrorIgnoreFlags
Dim blnEnableRedirects
Dim blnEnableHttpsToHttpRedirects
Dim strHostOverride
Dim strLogin
Dim strPassword
Dim strResponseText
Dim objWinHttp
lngTimeout = 59000
strUserAgentString = "http_requester/0.1"
intSslErrorIgnoreFlags = 13056 ' 13056: ignore all err, 0: accept no err
blnEnableRedirects = True
blnEnableHttpsToHttpRedirects = True
strHostOverride = ""
strLogin = ""
strPassword = ""
Set objWinHttp = CreateObject("WinHttp.WinHttpRequest.5.1")
objWinHttp.SetTimeouts lngTimeout, lngTimeout, lngTimeout, lngTimeout
objWinHttp.Open strMethod, strURL
If strMethod = "POST" Then
objWinHttp.setRequestHeader "Content-type", _
"application/x-www-form-urlencoded"
End If
If strHostOverride <> "" Then
objWinHttp.SetRequestHeader "Host", strHostOverride
End If
objWinHttp.Option(0) = strUserAgentString
objWinHttp.Option(4) = intSslErrorIgnoreFlags
objWinHttp.Option(6) = blnEnableRedirects
objWinHttp.Option(12) = blnEnableHttpsToHttpRedirects
If (strLogin <> "") And (strPassword <> "") Then
objWinHttp.SetCredentials strLogin, strPassword, 0
End If
On Error Resume Next
objWinHttp.Send(strPostData)
If Err.Number = 0 Then
If objWinHttp.Status = "200" Then
GetDataFromURL = objWinHttp.ResponseText
Else
GetDataFromURL = "HTTP " & objWinHttp.Status & " " & _
objWinHttp.StatusText
End If
Else
GetDataFromURL = "Error " & Err.Number & " " & Err.Source & " " & _
Err.Description
End If
On Error GoTo 0
Set objWinHttp = Nothing
End Function
'---------------------------------------------------------------------------
Function CheckURL(vURL)
On Error Resume Next
Dim xhr
Set xhr = CreateObject("MSXML2.ServerXMLHTTP.3.0")
xhr.Open "HEAD", vURL, false
xhr.Send
If Err.Number = 0 Then
'MsgBox xhr.status
CheckURL = xhr.status
Else
CheckURL = Err.Description
End If
End Function
'---------------------------------------------------------------------------

Answer 2

A simple function that ignores errors would work.
Function WaitIgnoreError(ByRef requestObject, timeout)
On Error Resume Next
WaitIgnoreError = requestObject.WaitForResponse(timeout)
End Function
Usage:
If WaitIgnoreError(http, 5) Then
body = http.responsetext
Else
response.write "Target url is not responding"
End If