How to Prevent dialog (Basic Authentication prompt) during call of Webservice - delphi

In a delphi program (running as a service) i need to call some webservices.
The calls works fine if basic Authentications is not requerired. The calls also works fine if Basic Authentication is requerired and username/password is provided (in BeforePost) using:
InternetSetOption(Data, INTERNET_OPTION_USERNAME,...
InternetSetOption(Data, INTERNET_OPTION_PASSWORD,...
But if Basic Authentication is Requeried, and username/password is not provided, the program brings up af prompt for the username/password (thats a NO-GO in a servcice).
So how can I signal that i DON'T want a prompt, but instead an error?
The problem is, as i can se it, in the SOAPHTTPTrans function THTTPReqResp.Send(const ASrc: TStream): Integer; (line 762 (second call to InternetErrorDlg i that method)).
EDIT1:
if i change the Flags in the beginning of the send method (in SOAPHTTPTRANS) to include INTERNET_FLAG_NO_AUTH, it works as i wanted.
But how do i do that without changing the SAOPHTTPTrans (if possible)?
EDIT2:
ws := THTTPRIO.Create(Self);
ws.URL := 'http://excample.com/ws.asmx';
ws.HTTPWebNode.InvokeOptions := [soIgnoreInvalidCerts];
ws.HTTPWebNode.OnBeforePost := WebServiceCallBeforePost;
AvailabilityWebservice := (ws as AvailabilityServiceSoap);
sTemp := AvailabilityWebservice.GetVersion;
Where AvailabilityServiceSoap is the interface generated using the WSDL importer.

I had this problem when trying to let Windows Live Messenger work through a web filter.
I ended up writing a small program that auto-authenticates every so often.
Hope this helps you too.
uses
... IdHTTP ...;
...
var
httpGetter: TIdHTTP;
...
httpGetter.Request.Username := username;
httpGetter.Request.Password := password;
httpGetter.HandleRedirects := True;
httpGetter.Request.BasicAuthentication := True;
//custom useragent required to let live messenger work
//this part is probably not necessary for your situation
httpGetter.Request.UserAgent := 'MSN Explorer/9.0 (MSN 8.0; TmstmpExt)';
httpGetter.Get(url,MS);
...

You could create a new class which Inherits from THTTPReqResp and override the send method so that you can include your own flags. You should be able to set ws.HTTPWebNode to a new node using the new class.
Something Like
ws := THTTPRIO.Create(Self);
MyNewNode := MyNewClass.Create;
ws.HTTPWebNode := MyNewNode;
ws.URL := 'http://excample.com/ws.asmx';
ws.HTTPWebNode.InvokeOptions := [soIgnoreInvalidCerts];
ws.HTTPWebNode.OnBeforePost := WebServiceCallBeforePost;
AvailabilityWebservice := (ws as AvailabilityServiceSoap);
sTemp := AvailabilityWebservice.GetVersion;

How about checking the servers authentication mode first?
http://en.wikipedia.org/wiki/Basic_access_authentication
The client asks for a page that
requires authentication but does not
provide a user name and password.
Typically this is because the user
simply entered the address or
followed a link to the page.
The server responds with the 401
response code and provides the
authentication realm.
So the client service application could send a Get and see if the response has a header like
WW-Authenticate: Basic realm="Secure Area"

Related

TIdHTTP.Get timeouts while the same call done with Postman succeeds: possible reasons?

I call a webapi with a Delphi app, in some pcs, the call timeouts, while in other it works fine.
The request done with Postman works fine.
It is a simple custom ping webservice (URL is in Edit1.Text in the code below), in fact the answer is a textual "Pong".
This is the Delphi code of the call:
errormsg := '';
{
old way of setting custom headers
IdHTTP1.Request.CustomHeaders.AddValue('X-HTTP-Method-Override', 'ForwardCommand');
IdHTTP1.Request.CustomHeaders.AddValue('Connection', 'keep-alive');
IdHTTP1.Request.CustomHeaders.AddValue('Accept', '*/*');
IdHTTP1.Request.CustomHeaders.AddValue('User-Agent', 'QualibusSilent');
IdHTTP1.Request.CustomHeaders.AddValue('Content-Type', 'text/plain');
}
//better way of setting custom headers
IdHTTP1.Request.MethodOverride := 'ForwardCommand';
IdHTTP1.Request.Connection := 'keep-alive';
IdHTTP1.Request.UserAgent := 'myCustomUserAgent';
IdHTTP1.Request.ContentType := 'text/plain';
IdHTTP1.Request.Accept := '*/*';
IdSSLIOHandlerSocketOpenSSL1 := TIdSSLIOHandlerSocketOpenSSL.Create(IdHTTP1);
IdSSLIOHandlerSocketOpenSSL1.SSLOptions.Mode := sslmClient;
IdSSLIOHandlerSocketOpenSSL1.SSLOptions.SSLVersions:=
[sslvTLSv1,sslvTLSv1_1,sslvTLSv1_2];
startTime := GetTickCount;
Try
sHTML := IdHTTP1.Get(Edit1.Text);
Except
On E:Exception do
errormsg := e.Message;
End;
EndTime := GetTickCount;
ShowMessage('Time taken: ' +
IntToStr(endTime-startTime)+#13#10+'Error:'+errormsg);
Basically it is a call where instead of GET I do a custom method (ForwardCommand) that I call with X-HTTP-Method-Override.
In the code above I tried to add many headers so that the call is really as the Postman one.
If the call is done directly to the IP address it works, but if I call the https URL it timeouts, there is no evidence of error in the proxy server.
Checking the logs at the webserver side it seems the call is not performed at all.
And this occurs only from some Windows 10 machines, while in the majority of them the call is performed correctly.
Could you please suggest which could be the cause of the error? What should I try to change in the Delphi code to avoid the timeout so that Delphi behaves like Postman?
Thanks.
As stated in comments:
Why when Tidhttp uses proxyParams timeout does not occur and the call succeeds?
...
I finally got the reason for the Postman vs Indy behavior: Proxy. By passing proxy IP and port to TIdHTTP it works, Postman manages to retrieve the system proxy automatically and therefore it works.
There is no "system proxy" on Windows, however there is a proxy in the WinInet API, which is what Internet Explorer (and Edge?) relies on.
In any case, it sounds like the failing PCs don't have direct access to the Internet to begin with, only through a proxy. Indy has no concept of any "system proxy" on any platform, so you will have to assign the proxy settings to TIdHTTP manually, as you have discovered.

Delphi Indy Sharepoint Windows Login

I am including these in uses clause
IdAuthentication
,
IdAuthenticationDigest
,
IdAuthenticationNTLM
,
IdAuthenticationSSPI
Currently I have code that does this:
W.Request.BasicAuthentication := True;
W.Request.Username := AOptionsPtr^.AuthUsername;
W.Request.Password := AOptionsPtr^.AuthPassword;
And if I have access to OpenSSL:
TmpOpenSSL := TIdSSLIOHandlerSocketOpenSSL.Create;
TmpOpenSSL.SSLOptions.Method := sslvSSLv23;
TmpOpenSSL.SSLOptions.Mode := sslmClient;
TmpOpenSSL.SSLOptions.VerifyMode := [];
TmpOpenSSL.SSLOptions.VerifyDepth := 0;
//--
W.IOHandler := TmpOpenSSL;
From skimming the documentation for WinINet (yes, I know it is not Indy) it seems persistent connections is also required for authentication. I suppose this also goes for Indy? URL:
http://msdn.microsoft.com/en-us/library/windows/desktop/aa384220(v=vs.85).aspx
I need to get this to work with SharePoint. The problem, however, is hat I have no intranet SharePoint server to test against. Thus I can not step through the code and see what works and what does not. However, I have a potential customer that can test it for me.
What more do I need to do to get above code working with SharePoint using Windows Authentication (NTML? SPPI?)
Will Indy automatically test and use proper auhentication?
do I need to set W.Request.BasicAuthentication := False; for auto authentication/detection to work?
If multiple requests are necessary (with first response being 401) I assume I need to add support for this in my own code when making a GET request? (To set authentication mode and make a new request?)
You can request a persistent connection by setting the Request.Connection property to 'keep-alive'.
TIdHTTP will check the server's WWW-Authorization header and compare it to the TIdAthentication classes you have included in your uses clause. The TIdHTTP.OnSelectAuthorization event will tell you which class was picked, and allow you to override it if needed. The TIdHTTP.OnAuthorization event will be triggered if authentication fails and different credentials are needed.
The BasicAuthrnication property simply allows TIdHTTP to fall back to TIdBasicAuthentication if no other TIdAuthentication class is assigned.
No, you do not need to handle multi-request authentications manually, like NTLM. TIdHTTP and TIdAuthentication handle those details for you.

Using a cookie with Indy

I'm trying to get data from a site using the Indy components. (This is in Delphi 7 but happy to use anything that works.)
If you go into a normal browser and put in the path:
http://inventory.data.xyz.com/provide_data.aspx?ID=41100&Mixed=no?fc=true&lang=en
it makes you tick a disclaimer before redirecting you to the actual site. This creates a cookie, which if I look at it in Firefox is like this:
http://inventory.data.xyz.com
Name: ASP.NET_SessionId
Content: vm4l0w033cdng5mevz5bkzzq
Path: /
Send For: Any type of connection
Expires: At end of session
I can't get through the disclaimer part using programming but I thought if I manually sign the disclaimer, I can then enter the details of the cookie into my code and connect directly to the data page. I have tried to do this with the code below but it only returns the html for the disclaimer page which tends to imply it's not using the cookie data I've given it. What am I doing wrong?
procedure TfmMain.GetWebpageData;
var
http: TIdHTTP;
cookie: TIdCookieManager;
sResponse: String;
begin
try
http := TIdHTTP.Create(nil);
http.AllowCookies := True;
http.HandleRedirects := True;
cookie := TIdCookieManager.Create(nil);
cookie.AddCookie('ASP.NET_SessionId=vm4l0w033cdng5mevz5bkzzq', 'inventory.data.xyz.com');
http.CookieManager := cookie;
sResponse := http.Get('http://inventory.data.xyz.com/provide_data.aspx?ID=41100&Mixed=no?fc=true&lang=en');
ShowMessage(sResponse); // returns text of disclaimer
except
end;
end;
Since you have not provided a real URL, I can only speculate, but chances are that either the cookie value you are providing to TIdCookieManager is wrong or outdated by the time TIdHTTP.Get() tries to use it, or more likely TIdCookieManager.AddCookie() is rejecting the cookie outright (if the TIdCookieManager.OnNewCookie event is not triggered, then the cookie was not accepted).

Delphi, WebBrowser, Google Login, FusionTable

I check a possibility to integrate fusiontables into my Delphi TWebBrowser based application.
But I cannot continue my project because I don't understand many things.
I have a public table, I want to access this, upload some rows, update some rows, and show it with fusiontablelayer. I have only "free" account now.
The problems:
1.)
I need to authenticate.
var
posts, s, url : string;
authToken : string;
postdata,
header : OleVariant;
params : TStringList;
i : integer;
begin
header := 'Content-type: application/x-www-form-urlencoded'#13#10;
params := TStringList.Create;
try
params.Values['accountType'] := 'GOOGLE';
params.Values['Email'] := 'any';
params.Values['Passwd'] := 'any';
params.Values['service'] := 'fusiontables';
params.Values['source'] := '?'; // WHAT IS THIS?
posts := EncodeParamsToURL(params);
finally
params.Free;
end;
postdata := VarArrayCreate([0, Length(posts) - 1], varByte);
// Put Post in array
for i := 1 to Length(posts) do
postdata[I - 1] := Ord(posts[I]);
url := 'https://www.google.com/accounts/ClientLogin';
wb.Navigate(url, emptyparam, emptyparam, postdata, header);
while wb.ReadyState <> READYSTATE_COMPLETE do
Application.ProcessMessages;
s := (wb.Document as iHTMLDocument2).body.innerText;
This is only a demo, but it is working.
I don't know what is "SOURCE" parameter, but I got three lines as result, and the last is "Auth=...." that containing the token.
http://code.google.com/intl/hu-HU/apis/fusiontables/docs/samples/apps_script.html
2.)
I need to push this token into header.
When I do this, I got 401 error.
params := TStringList.Create;
try
params.Text := s;
authToken := params.Values['Auth'];
finally
params.Free;
end;
header := 'Authorization : GoogleLogin auth="' + authToken + '"'#13#10;
url := 'http://www.google.com/fusiontables/api/query?select * from 1236944';
wb.Navigate(url, emptyparam, emptyparam, emptyparam, header);
So I'm totally confused now.
First:
Because JavaScript layer don't have authentication interface, I think I need to authenticate the "browser". May this is is wrong idea, but my thinking based on common web login logic, where the login creates a Session, and the Session is identified as a hidden cookie what is valid in this browser.
But may Google login is uses an identifier what passed on every request... I don't know.
So because this I must do an automatic "login" in the browser. (If that is not true then I can use WinInet, or IdHTTP for login, and use only the token in the browser).
Now I don't have idea how to do this login automatically without show the login name/pwd in the html, or show the token result in the TWebBrowser...
Second:
I must modify the data. This may realizable in a transparent component, like idHTTP, and I can show only the changes in the WebBrowser...
Third:
I can show the fusion table with a layer. This is not too hard if I has been authenticated once...
So: I'm confused now, because Google supports only Python/Java as client library, and not Delphi. I need to integrate the authentication and visualization into my TWebBrowser component very transparently.
But there is no good example or source in the net what demonstrate the login + fusiontable manipulation...
Can anybody help me in this question?
Question 1 is answered in section "The ClientLogin interface":
Source:
Short string identifying your application, for logging purposes. This
string should take the form: "companyName-applicationName-versionID".
Question 2:
Your URL is wrong, it has to be:
url := 'http://www.google.com/fusiontables/api/query?sql=select * from 1236944';
See the "sql=" -part? That's important. Have a look here for an example.
Regarding your other questions: they are a bit confusing. I think you don't have to use the TWebBrowser and can use anything that can issue GET and POST requests. For the login part: this information should be provided by your user, because your application should empower your users to work with their data, right?

Need a sample/demo of using TIdTelnet to interact with telnet server

I tried to employ Indy 10.5.5 (shipped with Delphi 2010) for:
connecting to telnet server
performing username/password authentication (gaining access to the command shell)
executing a command with returning resulting data back to application
and had no success, additionally i'm completely lost in spaghetti logic of Indy's internals and now have no idea why it didnt work or how i supposed to send strings to the server and grab the results. Need some sample code to study.
Formal form of the question: Where can i get 3-rd party contributed demo covering TIdTelnet component? (indyproject.org demos webpage do not have one)
The main problem with Telnet is that it DOES NOT utilize a command/response model like most other Internet protocols do. Either party can send data at any time, and each direction of data is independant from the other direction. This is reflected in TIdTelnet by the fact that it runs an internal reading thread to receive data. Because of this, you cannot simply connect, send a command, and wait for a response in a single block of code like you can with other Indy components. You have to write the command, then wait for the OnDataAvailable event to fire, and then parse the data to determine what it actually is (and be prepared to handle situations where partial data may be received, since that is just how TCP/IP works).
If you are connecting to a server that actually implements a command/response model, then you are better off using TIdTCPClient directly instead of TIdTelnet (and then implement any Telnet sequence decoding manually if the server really is using Telnet, which is rare nowadays but not impossible). For Indy 11, we might refactor TIdTelnet's logic to support a non-threaded version, but that is undecided yet.
done with indy.
no comments.. just som old code :-)
telnet don't like the send string kommand.. use sendch.
telnetdude.Host := 1.1.1.1;
try
telnetdude.connect;
except
on E: Exception do begin
E.CleanupInstance;
end; {except}
if telnetdude.Connected then begin
for i := 1 to length(StringToSend) do telnetdude.sendch(StringToSend[i]);
telnetdude.sendch(#13);
end;
end; {while}
end; {if}
if telnetdude.Connected then telnetdude.Disconnect;
end;
I hope this helps anyone looking for answers to a similar question.
Firstly, It would seem the typical command/response model (as mentioned above, does indeed NOT apply).
So I just got it working for some very simple application (rebooting my router).
Specific additions to above code from Johnny Lanewood (and perhaps some clarification)
a) You have to send #13 to confirm the command
b) I got "hangs" on every command I sent / response I requested UNTIL I enabled ThreadedEvent. (this was my big issue)
c) the OnDataAvailable event tells you when new data is available from the Telnet Server - however there are no guarantees as to what this data is - i.e. it's pretty what you get in the command line / what ever is appended to the previous responses. But is is NOT a specific response line to your command - it's whatever the telnet server returns (could be welcome info, ASCII drawings etc etc.)
Given (c) above, one would rather check the OnDataAvailable event and parse the data (knowing what you'd expect). When the output stops (i.e. you need build a mechanism for this), you can parse the data and determine whether the server is ready for something new from the client. For the purpose of my code below, I set a read timemout and I just used Sleep(2000) - ignorantly expecting no errors and that the server would be ready after the sleep for the next command.
My biggest stumbling block was ThreadedEvent := True (see above in b)
Thus, my working solution (for specific application, and possibly horrible to some).
lIDTelnet := TIdTelnet.Create(nil);
try
lIdTelnet.ReadTimeout := 30000;
lIDTelnet.OnDataAvailable := TDummy.Response;
lIDTelnet.OnStatus := TDummy.Status;
lIdTelnet.ThreadedEvent := True;
try
lIDTelnet.Connect('192.168.0.1', 23);
if not lIDTelnet.Connected then
Raise Exception.Create('192.168.0.1 TELNET Connection Failed');
Sleep(2000);
lIdtelnet.SendString(cst_user + #13);
Sleep(2000);
lIdtelnet.SendString(cst_pass + #13);
Sleep(2000);
lIdtelnet.SendString(cst_reboot + #13);
Sleep(2000);
if lIDTelnet.Connected then
lIDTelnet.Disconnect;
except
//Do some handling
end;
finally
FreeAndNil(lIdTelnet);
end;
and then
class procedure TDummy.Response(Sender: TIdTelnet; const Buffer: TIdBytes);
begin
Write(TDummy.ByteToString(Buffer));
end;
class function TDummy.ByteToString(
const aBytes: TIdBytes): String;
var
i : integer;
begin
result := '';
for i := 0 to Length(aBytes) -1 do
begin
result := result + Char(aBytes[i]);
end;
end;

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