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C#

OAuth2 using an HTTP Proxy (for a Desktop Application)

See more OAuth2 Examples

Shows how to send OAuth2 communications through an HTTP proxy in a desktop application, using Microsoft Graph as an example. This method applies to all OAuth2 applications.

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C#
bool success = false;

// This example requires the Chilkat API to have been previously unlocked.
// See Global Unlock Sample for sample code.

// To use an HTTP proxy with OAuth2, create a Chilkat socket object and specify the details.
Chilkat.Socket socket = new Chilkat.Socket();
// Use your HTTP proxy server domain or IP address.
socket.HttpProxyHostname = "myproxyserver.com";
// Change this to the listening port of your HTTP proxy server (if necessary)
socket.HttpProxyPort = 808;
// Specify login/password if needed.
socket.HttpProxyUsername = "myProxyLogin";
socket.HttpProxyPassword = "myProxyPassword";
socket.HttpProxyForHttp = true;

Chilkat.OAuth2 oauth2 = new Chilkat.OAuth2();

// We don't need to connect the socket beforehand.
// Just tell oauth2 to use the socket which has the HTTP proxy properties.
success = oauth2.UseConnection(socket);

// This should be the port in the localhost callback URL for your app.  
// The callback URL would look like "http://localhost:3017/" if the port number is 3017.
oauth2.ListenPort = 3017;

oauth2.AuthorizationEndpoint = "https://login.microsoftonline.com/common/oauth2/v2.0/authorize";
oauth2.TokenEndpoint = "https://login.microsoftonline.com/common/oauth2/v2.0/token";

// Replace these with actual values.
oauth2.ClientId = "MICROSOFT-GRAPH-CLIENT-ID";
// This is your app password:
oauth2.ClientSecret = "MICROSOFT-GRAPH-CLIENT-SECRET";

oauth2.CodeChallenge = false;
// Provide a SPACE separated list of scopes.
// See https://developer.microsoft.com/en-us/graph/docs/authorization/permission_scopes 

// Important: To get a refresh token in the final response, you have to ask for "offline_access" scope
oauth2.Scope = "openid profile offline_access user.readwrite mail.readwrite mail.send files.readwrite";

// Begin the OAuth2 Authorization code flow.  This returns a URL that should be loaded in a browser.
string url = oauth2.StartAuth();
if (oauth2.LastMethodSuccess != true) {
    Debug.WriteLine(oauth2.LastErrorText);
    return;
}

Debug.WriteLine("url = " + url);

// Launch the default browser on the system and navigate to the url.
// The LaunchBrowser method was added in Chilkat v10.1.2.
success = oauth2.LaunchBrowser(url);
if (success == false) {
    Debug.WriteLine(oauth2.LastErrorText);
    return;
}

// Wait for the user to approve or deny authorization in the browser.
int numMsWaited = 0;
while ((numMsWaited < 90000) && (oauth2.AuthFlowState < 3)) {
    oauth2.SleepMs(100);
    numMsWaited = numMsWaited + 100;
}

// If the browser does not respond within the specified time, AuthFlowState will be:
// 
// 1: Waiting for Redirect - The OAuth2 background thread is waiting for the browser's redirect request.
// 2: Waiting for Final Response - The thread is awaiting the final access token response.
// In either case, cancel the background task initiated by StartAuth.

if (oauth2.AuthFlowState < 3) {
    oauth2.Cancel();
    Debug.WriteLine("No response from the browser!");
    return;
}

// Check AuthFlowState to determine if authorization was granted, denied, or failed:
// 
// 3: Success - OAuth2 flow completed, the background thread exited, and the successful response is in AccessTokenResponse.
// 4: Access Denied - OAuth2 flow completed, the background thread exited, and the error response is in AccessTokenResponse.
// 5: Failure - OAuth2 flow failed before completion, the background thread exited, and error details are in FailureInfo.

if (oauth2.AuthFlowState == 5) {
    Debug.WriteLine("OAuth2 failed to complete.");
    Debug.WriteLine(oauth2.FailureInfo);
    return;
}

if (oauth2.AuthFlowState == 4) {
    Debug.WriteLine("OAuth2 authorization was denied.");
    Debug.WriteLine(oauth2.AccessTokenResponse);
    return;
}

if (oauth2.AuthFlowState != 3) {
    Debug.WriteLine("Unexpected AuthFlowState:" + Convert.ToString(oauth2.AuthFlowState));
    return;
}

Debug.WriteLine("OAuth2 authorization granted!");
Debug.WriteLine("Access Token = " + oauth2.AccessToken);

// Get the full JSON response:
Chilkat.JsonObject json = new Chilkat.JsonObject();
json.Load(oauth2.AccessTokenResponse);
json.EmitCompact = false;

// The JSON response looks like this:

// {
//   "token_type": "Bearer",
//   "scope": "User.Read Mail.ReadWrite Mail.Send",
//   "expires_in": 3600,
//   "ext_expires_in": 0,
//   "access_token": "EwBAA8l6B...",
//   "refresh_token": "MCRMdbe...",
//   "id_token": "eyJ0eXA..."
// }

// If an "expires_on" member does not exist, then add the JSON member by
// getting the current system date/time and adding the "expires_in" seconds.
// This way we'll know when the token expires.
if (json.HasMember("expires_on") != true) {
    Chilkat.CkDateTime dtExpire = new Chilkat.CkDateTime();
    dtExpire.SetFromCurrentSystemTime();
    dtExpire.AddSeconds(json.IntOf("expires_in"));
    json.AppendString("expires_on",dtExpire.GetAsUnixTimeStr(false));
}

Debug.WriteLine(json.Emit());

// Save the JSON to a file for future requests.
Chilkat.FileAccess fac = new Chilkat.FileAccess();
fac.WriteEntireTextFile("qa_data/tokens/microsoftGraph.json",json.Emit(),"utf-8",false);