[RESOLVED] Sending HTTP requests

[skankerer]

GET http://www.vbforums.com/index.html HTTP/1.1

Host: www.vbforums.com
User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.8.0.7) Gecko/20060909 Firefox/1.5.0.7
Accept: text/xml,application/xml,application/xhtml+xml,text/html;q=0.9,text/plain;q=0.8,image/png,*/*;q=0.5
Accept-Language: en-us,en;q=0.5
Accept-Encoding: gzip,deflate
Accept-Charset: ISO-8859-1,utf-8;q=0.7,*;q=0.7
Keep-Alive: 300
Connection: keep-alive

How should I go about sending http requests etc with winsock? I know they need to include a header and a GET / POST request.

[Jean.B]

WEll you need to connect to the host (in this case www.vbforums.com) and send the request, dont forget about the blank lines (vbcrlf) they are important, in the request end usually there are 2 blank lines as i remember!
And this: "Accept-Encoding: gzip,deflate" shows you will get the output data compressed with gzip/deflate, to recieve uncompressed text just do: "Accept-Encoding:".

[skankerer]

Ok I got it happening but when I get the response I'm not sure how to seperate the server's response, e.g.

Recommend an exact RFC for me to read?

HTTP/1.1 200 OK
Date: Mon, 23 Oct 2006 12:29:35 GMT
Server: Apache
'PHPBBCOOKIE
PHPBBCOOKIE
PHPBBCOOKIE
PHPBBCOOKIE
Expires: 0
Cache-Control: private, post-check=0, pre-check=0, max-age=0
Pragma: no-cache
Content-Length: 111948
Connection: close
Content-Type: text/html; charset=ISO-8859-1


Thanks.

[Jean.B]

Well next you send the http request to the next page you want to go..collect cookies if they are sent, some sites checks checksum, if its wrong then it usually server sends you message back about wrong checksum.

[DigiRev]

Ok I got it happening but when I get the response I'm not sure how to seperate the server's response, e.g.

Recommend an exact RFC for me to read?

HTTP/1.1 200 OK
Date: Mon, 23 Oct 2006 12:29:35 GMT
Server: Apache
'PHPBBCOOKIE
PHPBBCOOKIE
PHPBBCOOKIE
PHPBBCOOKIE
Expires: 0
Cache-Control: private, post-check=0, pre-check=0, max-age=0
Pragma: no-cache
Content-Length: 111948
Connection: close
Content-Type: text/html; charset=ISO-8859-1


Thanks.

Do you mean parsing out individual things like content-length, cache-control, etc.? If so, you could use something like this:

Option Explicit
 
'Function to get the value of an HTTP variable.
'Used for parsing HTTP server responses.
Private Function GetHTTPVar(ByVal Name As String, ByVal HTTPData As String) As String
    Dim lonPos As Long, lonLenName As Long
    Dim strRet As String, lonLen As Long
    Dim lonCrLf As Long
    
    lonLenName = Len(Name)
    lonLen = Len(HTTPData)
    lonPos = InStr(1, HTTPData, Name, vbTextCompare)
    
    If lonPos > 0 Then
        lonCrLf = InStr(lonPos + 1, HTTPData, vbNewLine)
        GetHTTPVar = Mid$(HTTPData, (lonPos + lonLenName), (lonCrLf - (lonPos + lonLenName)))
    End If
    
End Function
 
Private Sub Form_Load()
    Dim strHTTP As String
    
    'Build some data to test with.
    strHTTP = "HTTP/1.1 200 OK" & vbNewLine & _
        "Date: Mon, 23 Oct 2006 12:29:35 GMT" & vbNewLine & _
        "Server: Apache" & vbNewLine & _
        "Expires: 0" & vbNewLine & _
        "Cache-Control: private, post-check=0, pre-check=0, max-age=0" & vbNewLine & _
        "Pragma: no-cache" & vbNewLine & _
        "Content-Length: 111948" & vbNewLine & _
        "Connection: Close" & vbNewLine & _
        "Content-Type: text/html; charset=ISO-8859-1" & vbNewLine & vbNewLine
    
    
    Dim strVar As String
    
    'Get the Cache-Control variable.
    strVar = GetHTTPVar("Cache-Control: ", strHTTP)
    MsgBox strVar
End Sub

[m_vaghasiya]

Well if you want to send HTTP request to the server, the best idea would be XMLHTTP object. That would be simple to user other than going with winsock.

[DrGonzo]

Hello, I was also experimenting a little bit with HTTP and wrote this really little program.
It only requests and receives a page which will be shown unformatted in a simple TextBox.

What was your intention to it? Mine was a code-request in another forum, where someone wanted to log himself into a html-site by a vb-program.
I suggested him to read this RFC: http://www.ietf.org/rfc/rfc2616.txt

It would be nice if you could post your code as well. Just because I'm interested into comparing it etc. .

Here is the complete Code of it:

'1 TextBox: name-> txtOut
'1 TextBox: name-> txtURL
'1 CommandButton: name-> cmdGo
 
Option Explicit
 
Private InetData As String
Private URL As String
 
Private Sub cmdGo_Click()
txtOut.Text = ""
If Winsock1.State <> sckClosed Then Winsock1.Close
    Winsock1.Connect URL, 80
End Sub
 
Private Sub Form_Load()
        URL = txtURL.Text
End Sub
 
Private Sub txtURL_Change()
    URL = txtURL.Text
End Sub
 
Private Sub Winsock1_Connect()
    Call GetWebpage(Winsock1)
 
End Sub
 
Private Sub Winsock1_DataArrival(ByVal bytesTotal As Long)
    Winsock1.GetData InetData
    txtOut.Text = txtOut.Text & InetData
End Sub
 
Public Sub GetWebpage(wsk As Winsock)
 
With wsk
    .SendData "GET /" & " HTTP/1.1" & vbCrLf
    .SendData "Accept: text/plain" & vbCrLf
    .SendData "Accept-Language: en-us" & vbCrLf
    '.SendData "Accept-Encoding: gzip, deflate" & vbCrLf
    '.SendData "User-Agent: Mozilla/4.0 (compatible; MSIE 5.0; Windows 98; DigExt)" & vbCrLf
    .SendData "Host: " & wsk.LocalIP & vbCrLf
    .SendData "Connection: Keep-Alive" & vbCrLf & vbCrLf
End With
 
End Sub

[DigiRev]

Hello, I was also experimenting a little bit with HTTP and wrote this really little program.
It only requests and receives a page which will be shown unformatted in a simple TextBox.

What was your intention to it? Mine was a code-request in another forum, where someone wanted to log himself into a html-site by a vb-program.
I suggested him to read this RFC: http://www.ietf.org/rfc/rfc2616.txt

It would be nice if you could post your code as well. Just because I'm interested into comparing it etc. .

Here is the complete Code of it:

'1 TextBox: name-> txtOut
'1 TextBox: name-> txtURL
'1 CommandButton: name-> cmdGo
 
Option Explicit
 
Private InetData As String
Private URL As String
 
Private Sub cmdGo_Click()
txtOut.Text = ""
If Winsock1.State <> sckClosed Then Winsock1.Close
    Winsock1.Connect URL, 80
End Sub
 
Private Sub Form_Load()
        URL = txtURL.Text
End Sub
 
Private Sub txtURL_Change()
    URL = txtURL.Text
End Sub
 
Private Sub Winsock1_Connect()
    Call GetWebpage(Winsock1)
 
End Sub
 
Private Sub Winsock1_DataArrival(ByVal bytesTotal As Long)
    Winsock1.GetData InetData
    txtOut.Text = txtOut.Text & InetData
End Sub
 
Public Sub GetWebpage(wsk As Winsock)
 
With wsk
    .SendData "GET /" & " HTTP/1.1" & vbCrLf
    .SendData "Accept: text/plain" & vbCrLf
    .SendData "Accept-Language: en-us" & vbCrLf
    '.SendData "Accept-Encoding: gzip, deflate" & vbCrLf
    '.SendData "User-Agent: Mozilla/4.0 (compatible; MSIE 5.0; Windows 98; DigExt)" & vbCrLf
    .SendData "Host: " & wsk.LocalIP & vbCrLf
    .SendData "Connection: Keep-Alive" & vbCrLf & vbCrLf
End With
 
End Sub

I wouldn't use multiple .SendData methods like that.

Instead, build all that data into a string variable, and send it off as one packet. ie:

strData = "GET /" & " HTTP/1.1" & vbCrLf
strData = strData & "Accept: text/plain" & vbCrLf
'etc..
.SendData strData
strData = ""