How can I edit the code to accept proxy?
CallHttp functions
Public Shared Function CallHttp(ByVal url As String, _
ByVal params As String, _
ByVal httpPost As Boolean) As String
If httpPost Then
Return CallHttpPost(url, params)
Else
Return CallHttpGet(url, params)
End If
End Function
CallHttpPost function:
Protected Shared Function CallHttpPost(ByVal url As String, _
ByVal params As String) As String
Dim loHttp As HttpWebRequest
'params = QueryStringEncode(params, TypeEncodeEnum.urlEncode)
loHttp = CType(WebRequest.Create(url), HttpWebRequest)
loHttp.Method = "POST"
Dim requestWriter As StreamWriter = New StreamWriter(loHttp.GetRequestStream())
If Not String.IsNullOrEmpty(params) Then
requestWriter.Write(params)
End If
requestWriter.Close()
loHttp.ContentType = "application/x-www-form-urlencoded"
loHttp.Headers.Set("Pragma", "no-cache")
loHttp.AllowAutoRedirect = True
loHttp.KeepAlive = True
loHttp.Timeout = 30 * 1000
'loHttp.Referer = url
Dim loWebResponse As HttpWebResponse = CType(loHttp.GetResponse(), HttpWebResponse)
Dim enc As Encoding = System.Text.Encoding.UTF8
Dim loResponseStream As StreamReader = New StreamReader(loWebResponse.GetResponseStream(), enc)
Dim lcHtml As String = loResponseStream.ReadToEnd()
loWebResponse.Close()
loResponseStream.Close()
Return lcHtml
End Function
Im behind a corporate firewall and I get a 407 proxy authentication required error if I use the function like this
strXML = CallHttp(API_URL, sb.ToString, False)
any ideas?
user and pass are the authentication of your proxy
Dim myProxy As New WebProxy("192.168.1.2:8080")
Dim authentication As New System.Net.NetworkCredential("user", "pwd")
myProxy.Credentials = authentication
Dim loHttp As HttpWebRequest
loHttp .Proxy = myProxy
Related
I'm writing an .NET application that uses HttpClient to connect to the API and retrieve video.
The Documentation provided for "Cookie-based authentication" details the following to login:
Call GET /api/getNonce
In response you'll get a JSON object with realm and nonce (nonce is a session key for this user)
Calculate authentication hash auth_digest, using realm and nonce (see algorithm below)
Call and pass the "auth" parameter in the json request body GET /api/cookieLogin
Server will check authentication and set session cookies
Which then expands on "Calculating Authentication Hash" with the following steps:
Call GET /api/getNonce
In response you'll get a JSON object with realm and nonce
Translate user's username to the lower case
Check the required method ("GET" for HTTP GET requests, "POST" for HTTP POST
requests, "PLAY" for RTSP etc)
digest = md5_hex(user_name + ":" + realm + ":" + password)
partial_ha2 = md5_hex(method + ":")
simplified_ha2 = md5_hex(digest + ":" + nonce + ":" + partial_ha2)
auth_digest = base64(user_name + ":" + nonce + ":" + simplified_ha2)
Here auth_digest is the required authentication hash
I use this Article written in C# as a reference, converted it to VB.NET, change a little bit of code in it according to the requirement above and then implemented it into my program. But I always get an error like this
"The remote server returned an error: (403) Forbidden."
When I debug the program, the problem appears when reading DigestAuthFixer.vb class in GrabResponse Function on this line response = CType(request2.GetResponse(), HttpWebResponse) . I suspect that "auth_digest" didn't return the correct value so the web service to deny the request with a 403 error. My question is how to properly implement digest authentication using VB.Net ? Are there any standard methods or do I have to do it from scratch? Thanks in advance.
This is the code that I use to connect to the API and retrieve the video:
Download HTTPClient
Private Shared _host As String = "http://127.0.0.1:7001"
Private Shared _username As String = "user"
Private Shared _password As String = "password"
Dim auto As Boolean = False
Shared ReadOnly client As HttpClient = New HttpClient()
Public Async Function Download_HttpClient(ByVal cameraID As String _
, ByVal videoDT As String _
, ByVal duration As String _
, ByVal resolution As String _
, ByVal path As String) As Task(Of String)
Dim cookieContainer As New CookieContainer
Dim httpClientHandler As New HttpClientHandler
httpClientHandler.AllowAutoRedirect = True
httpClientHandler.UseCookies = True
httpClientHandler.CookieContainer = cookieContainer
Dim httpClient As New HttpClient(httpClientHandler)
Dim err As Boolean = False
Dim downloadFileName As String
'SET HTTPCLIENT HEADERS
httpClient.DefaultRequestHeaders.Add("User-Agent", "Mozilla/5.0 (compatible; MSIE 10.0; Windows NT 6.1; WOW64; Trident/6.0)")
'httpClient.DefaultRequestHeaders.Add("Accept", "text/html,application/xhtml+xml,application/xml")
httpClient.DefaultRequestHeaders.Add("Accept", "text/html,application/xhtml+json,application/json")
httpClient.DefaultRequestHeaders.Add("Accept-Charset", "ISO-8859-1")
Dim downloadId As String = Nothing
Try
ServicePointManager.SecurityProtocol = SecurityProtocolType.Ssl3 Or SecurityProtocolType.Tls12 Or SecurityProtocolType.Tls11 Or SecurityProtocolType.Tls
'GET USER RIGHTS
Dim login_url As String = _host + "/api/getNonce"
Dim login_parameter As String = "?user_name =" + _username + "&password=" + _password
Dim login_response As HttpResponseMessage = Await httpClient.GetAsync(login_url + login_parameter)
Dim login_contents As String = Await login_response.Content.ReadAsStringAsync()
'CALCULATE AUTHENTICATION HASH
Dim dir As String = "/dir/index.html"
Dim url As String = _host + "/api/getNonce"
Dim digest As NUI.DigestAuthFixer = New NUI.DigestAuthFixer(url, _username.ToLower, _password)
Dim auth As String = digest.GrabResponse(dir)
'CALL POST /api/cookieLogin
Dim client As HttpClient = New HttpClient
client.DefaultRequestHeaders.Accept.Add(New System.Net.Http.Headers.MediaTypeWithQualityHeaderValue("application/json"))
Dim postData As New List(Of KeyValuePair(Of String, String))
postData.Add(New KeyValuePair(Of String, String)("auth_digest ", auth))
Dim content As New FormUrlEncodedContent(postData)
content.Headers.ContentType = New Headers.MediaTypeHeaderValue("application/x-runtime-guid")
Dim response As HttpResponseMessage = client.PostAsync(New Uri(_host + "/api/cookieLogin"), content).Result
If response.IsSuccessStatusCode Then
MsgBox("POST CookieLogin Successfully")
Else
MsgBox(response)
End If
Catch ex As Exception
MessageBox.Show("Invalid response from the server due to connection limitation or firewall blocking your request")
Return ex.ToString()
End Try
'CREATE DOWNLOAD URL
Dim download_url As String = _host + "/media/" + cameraID + ".mkv"
Dim download_param As String = "?pos=" + videoDT + "&duration=" + duration + "&resolution=" + resolution
Dim downloadFile As String = download_url + download_param
'GET REQUEST AND DOWNLOAD
Dim file_response = Await httpClient.GetAsync(downloadFile)
Dim file_header = file_response.Content.Headers.GetValues("Content-Disposition")
Dim temp_string() As String = file_header.ToArray()
temp_string = temp_string(0).Split("=")
downloadFileName = temp_string(1).Replace("""", "")
Try
Using fs As New FileStream(path & downloadFileName, FileMode.Create)
Await file_response.Content.CopyToAsync(fs)
End Using
Catch ex As Exception
MessageBox.Show("Directory does not exists, please manually change the folder target")
Return ex.ToString()
End Try
Return "Download successfully"
End Function
DigestAuthFixer.vb class
Imports System
Imports System.Collections.Generic
Imports System.Linq
Imports System.Text
Imports System.Security.Cryptography
Imports System.Text.RegularExpressions
Imports System.Net
Imports System.IO
Imports System.Net.Http
Namespace NUI
Public Class DigestAuthFixer
Private Shared _host As String
Private Shared _user As String
Private Shared _password As String
Private Shared _realm As String
Private Shared _nonce As String
Private Shared _qop As String
Private Shared _cnonce As String
Private Shared _cnonceDate As DateTime
Private Shared _nc As Integer
Public Sub New(ByVal host As String, ByVal user As String, ByVal password As String)
_host = host
_user = user
_password = password
End Sub
Private Function CalculateMd5Hash(ByVal input As String) As String
Dim inputBytes As Byte() = Encoding.GetEncoding("ISO-8859-1").GetBytes(input)
Dim hash = MD5.Create().ComputeHash(inputBytes)
Dim sb As New System.Text.StringBuilder()
For Each b In hash
sb.Append(b.ToString("x2"))
Next b
Return sb.ToString()
End Function
Private Function GrabHeaderVar(ByVal varName As String, ByVal header As String) As String
Dim regHeader = New Regex(String.Format("{0}=""([^""]*)""", varName))
Dim matchHeader = regHeader.Match(header)
If matchHeader.Success Then Return matchHeader.Groups(1).Value
Throw New ApplicationException(String.Format("Header {0} not found", varName))
End Function
Private Function GetDigestHeader(ByVal dir As String) As String
Dim digest = CalculateMd5Hash(_user.ToLower + ":" + _realm + ":" + _password)
Dim partial_ha2 = CalculateMd5Hash("GET" + ":")
Dim simplified_ha2 = CalculateMd5Hash(digest + ":" + _nonce + ":" + partial_ha2)
Dim auth_digest = (_user.ToLower + ":" + _nonce + ":" + simplified_ha2)
Return auth_digest
End Function
Public Function GrabResponse(ByVal dir As String) As String
Dim url = _host & dir
Dim uri = New Uri(url)
Dim request = CType(WebRequest.Create(uri), HttpWebRequest)
If Not String.IsNullOrEmpty(_cnonce) AndAlso DateTime.Now.Subtract(_cnonceDate).TotalHours < 1.0 Then
request.Headers.Add("Authorization", GetDigestHeader(dir))
End If
Dim response As HttpWebResponse
Try
response = CType(request.GetResponse(), HttpWebResponse)
Catch ex As WebException
If ex.Response Is Nothing OrElse (CType(ex.Response, HttpWebResponse)).StatusCode <> HttpStatusCode.Unauthorized Then Throw
Dim wwwAuthenticateHeader = ex.Response.Headers("WWW-Authenticate")
_realm = GrabHeaderVar("realm", wwwAuthenticateHeader)
_nonce = GrabHeaderVar("nonce", wwwAuthenticateHeader)
_qop = "auth"
_nc = 0
_cnonce = New Random().[Next](123400, 9999999).ToString()
_cnonceDate = DateTime.Now
Dim request2 = CType(WebRequest.Create(uri), HttpWebRequest)
request2.Headers.Add("Authorization", GetDigestHeader(dir))
response = CType(request2.GetResponse(), HttpWebResponse)
End Try
Dim reader = New StreamReader(response.GetResponseStream())
Return reader.ReadToEnd()
End Function
End Class
End Namespace
I tried reading a webpage into my program using vb.net's HttpWebRequest. My problem has to do with figuring out the encoding of the web page before I actually read it into a string. When I read it in, some characters appear as diamonds with question-marks inside the diamonds. The web page itself looks fine in a browser, its just when I read it in that some characters aren't encoded right.
The original code I used was:
Dim myWebRequest As HttpWebRequest = WebRequest.Create(ourUri)
Dim myWebResponse As httpWebResponse = myWebRequest.GetResponse()
Then to try to get the encoding. I used:
Dim contentType As String = myWebResponse.ContentType
Dim charset As String = myWebResponse.CharacterSet
But both 'contentType' and 'charset' end up with the value 'text/html'. What I want to know is if the webpage is encoded in 'utf-8' or some other character set, so I can later retrieve it like this:
Dim receiveStream As Stream = myWebResponse.GetResponseStream()
Dim encode As Encoding = System.Text.Encoding.GetEncoding(charset)
Using reader As StreamReader = New StreamReader(receiveStream, encode)
So to sum up, there seems to be no way to inquire what the encoding is, and then use the answer to read the webpage the right way.
Is that true? Any help is appreciated.
The entire code of the routine (asked for by a commenter) follows:
Public Shared Function DownloadFileUsingURL(ByVal URLstring As String, ByVal descFilePathAndName As String, ByRef errorMessage As String, ByRef hadRedirect As Boolean,
ByRef newURL As String, ByRef isSecureConnection As Boolean, ByVal didSupplyfullfilename As Boolean, ByRef downloadedcontent As String,
ByRef httpTohttps As Boolean, ByRef httpsTohttp As Boolean, ByRef BytesRead As Integer) As Boolean
Dim ourUri As New Uri(URLstring)
Dim csh As New ClassSyncHttp
Dim expectSecureConnection As Boolean
Dim domainchanged As Boolean
newURL = ""
errorMessage = ""
hadRedirect = False
httpTohttps = False
httpsTohttp = False
isSecureConnection = False
If URLstring.ToLower.StartsWith("https:") Then
ServicePointManager.Expect100Continue = True
ServicePointManager.SecurityProtocol = SecurityProtocolType.SystemDefault
expectSecureConnection = True
Else
ServicePointManager.SecurityProtocol = SecurityProtocolType.SystemDefault
expectSecureConnection = False
End If
Try
Dim myWebRequest As HttpWebRequest = WebRequest.Create(ourUri) ' I changed webrequest to httpwebrequest
Dim cookieContainer As CookieContainer = New CookieContainer ' needs httpwebrequest to work
myWebRequest.CookieContainer = cookieContainer
myWebRequest.Proxy.Credentials = System.Net.CredentialCache.DefaultCredentials
myWebRequest.UserAgent = "BrowseNet"
myWebRequest.Timeout = ClassGlobalVariables.downloadTimeoutMilliseconds
myWebRequest.Credentials = CredentialCache.DefaultCredentials
Dim myWebResponse As HttpWebResponse = myWebRequest.GetResponse()
Dim contentType As String = myWebResponse.ContentType
Dim charset As String = myWebResponse.CharacterSet
If Not ourUri.Equals(myWebResponse.ResponseUri) Then
newURL = myWebResponse.ResponseUri.ToString
hadRedirect = True
If newURL.ToLower.StartsWith("https") Then
isSecureConnection = True
End If
compareURLs(URLstring, newURL, httpTohttps, domainchanged)
End If
Dim receiveStream As Stream = myWebResponse.GetResponseStream()
If didSupplyfullfilename Then
Using fs As FileStream = File.Create(descFilePathAndName)
receiveStream.CopyTo(fs)
BytesRead = fs.Length
End Using
Else
Dim encode As Encoding = System.Text.Encoding.GetEncoding(charset)
Using reader As StreamReader = New StreamReader(receiveStream, encode)
' receiveStream.Seek(0, SeekOrigin.Begin)
downloadedcontent = reader.ReadToEnd()
BytesRead = downloadedcontent.Length
End Using
End If
myWebResponse.Close()
If expectSecureConnection Then
isSecureConnection = True
Else
isSecureConnection = False
End If
Return True
Catch ex As webException
If expectSecureConnection Then
' guessing here that the problem was that was wrong about secure connection. (Problem could be elsewhere, of course)
isSecureConnection = False
httpsTohttp = True
If ex.HResult = System.Net.WebExceptionStatus.SecureChannelFailure Then
' not sure what to do
End If
'Else
' isSecureConnection = True
End If
errorMessage = ex.Message
Return False
End Try
End Function
i am try send raw data into PUT method , but i am getting error as "The remote server returned an error: (502) Bad Gateway"
But same data i try to use in Postman Agent, its working.
What i tried
Private Function SendRequest(uri As Uri, jsonDataBytes As Byte(), contentType As String, method As String) As String
Dim req As WebRequest = WebRequest.Create(uri)
req.ContentType = contentType
req.Method = method
req.ContentLength = jsonDataBytes.Length
req.Headers.Add("x-api-key:xxxxxY0tZN55jbXnY05Oxxxxx")
Dim stream = req.GetRequestStream()
stream.Write(jsonDataBytes, 0, jsonDataBytes.Length)
stream.Close()
Dim response = req.GetResponse().GetResponseStream()
Dim reader As New StreamReader(response)
Dim res = reader.ReadToEnd()
reader.Close()
response.Close()
Return res
End Function
Calling function
Dim postdata As String = "[{barcod:A0000041},{barcode:A0000113}]"
Dim data = Encoding.UTF8.GetBytes(postdata)
Dim Uri As New Uri("https://sample.com/xxxxx/xxxxx?funcName=UpdateBaarcode")
Dim result_post = SendRequest(Uri, data, "text/plain", "PUT")
What i missing , pls reply.
Regards,
Aravind
For REST API
I use WebRequest using DirectCast.
It's been so long I can't remember why. TT
Try like the code below.
Private Function SendRequest(uri As Uri, jsonDataBytes As Byte(), contentType As String, method As String) As String
Dim req As HttpWebRequest= DirectCast(WebRequest.Create(uri), HttpWebRequest)
req.ContentType = contentType
req.Method = method
req.ContentLength = jsonDataBytes.Length
req.Headers.Add("x-api-key:xxxxxY0tZN55jbXnY05Oxxxxx")
Dim stream = req.GetRequestStream()
stream.Write(jsonDataBytes, 0, jsonDataBytes.Length)
stream.Close()
Dim response = DirectCast(req.GetResponse(), HttpWebResponse)
Dim reader As New StreamReader(response.GetResponseStream)
Dim res = reader.ReadToEnd()
reader.Close()
response.Close()
Return res
End Function
I have the following code to send a WebRequest to Betfair, usually this would be sent from a browser and it would send cookie data with it to identify my login, how would I go about attaching the cookie data to this request? (I need to find out how to extract the cookie data first, if anyone can point to any useful articles relating to that it would be much appreciated).
Private Sub Place_Bet(ByVal marketId As String, selectionId As String)
Dim url As Uri
url = New Uri("https://etx.betfair.com/www/etx-json-rpc?_ak=nzIFcwyWhrlwYMrh&alt=json")
Dim json As String = "[{""method"":""ExchangeTransactional/v1.0/place....}]"
Dim data = Encoding.UTF8.GetBytes(json)
Dim result_post = SendRequest(url, data, "application/json", "POST")
MsgBox(result_post)
End Sub
Private Function SendRequest(uri As Uri, jsonDataBytes As Byte(), contentType As String, method As String) As String
Dim response As String
Dim request As WebRequest
request = WebRequest.Create(uri)
request.ContentLength = jsonDataBytes.Length
request.ContentType = contentType
request.Method = method
Using requestStream = request.GetRequestStream
requestStream.Write(jsonDataBytes, 0, jsonDataBytes.Length)
requestStream.Close()
Using responseStream = request.GetResponse.GetResponseStream
Using reader As New StreamReader(responseStream)
response = reader.ReadToEnd()
End Using
End Using
End Using
Return response
End Function
When using a WebRequest I can add the system default proxy and the default credentials like this
WebRequest = System.Net.WebRequest.Create(URL)
WebRequest.Method = "GET"
WebRequest.ContentType = "application/x-www-form-urlencoded"
WebRequest.Headers.Add("...some headers here...")
WebRequest.Credentials = CRED
WebRequest.Proxy = System.Net.WebRequest.GetSystemWebProxy
WebRequest.Proxy.Credentials = System.Net.CredentialCache.DefaultNetworkCredentials
Public Shared Function MultipartFormDataPost(ByVal postUrl As String, ByVal postParameters As Dictionary(Of String, Object)) As HttpWebResponse
Dim formDataBoundary As String = String.Format("----------{0:N}", Guid.NewGuid())
Dim contentType As String = "multipart/form-data; boundary=" & formDataBoundary
Dim formData As Byte() = GetMultipartFormData(postParameters, formDataBoundary)
Return PostForm(postUrl, contentType, formData)
End Function
Private Shared Function PostForm(ByVal postUrl As String, ByVal contentType As String, ByVal formData As Byte()) As HttpWebResponse
Dim request As HttpWebRequest = TryCast(WebRequest.Create(postUrl), HttpWebRequest)
If request Is Nothing Then
Throw New NullReferenceException("request is not a http request")
End If
request.Method = "POST"
request.ContentType = contentType
request.Credentials = CRED
request.Headers.Add(EBC_TP_ZUGANG)
request.CookieContainer = New CookieContainer()
request.ContentLength = formData.Length
request.Proxy = System.Net.WebRequest.GetSystemWebProxy
request.Proxy.Credentials = System.Net.CredentialCache.DefaultNetworkCredentials
Using requestStream As Stream = request.GetRequestStream()
requestStream.Write(formData, 0, formData.Length)
requestStream.Close()
End Using
Return TryCast(request.GetResponse(), HttpWebResponse)
End Function
What do I have to do when I need to add that proxy to a HttpWebResponse?
This is my code:
Dim postURL As String = "https://www.server.com/blabbla"
Dim webResponse As HttpWebResponse = clsFileUpload.MultipartFormDataPost(postURL, postParameters)
Dim responseReader As StreamReader = New StreamReader(webResponse.GetResponseStream())
Dim fullResponse As String = responseReader.ReadToEnd()
webResponse.Close()