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Xojo Plugin Requires Chilkat v10.1.2+

GitHub OAuth2 Access Token

See more OAuth2 Examples

Demonstrates how to get a GitHub OAuth2 access token from a desktop application or script.

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Xojo Plugin
Dim success As Boolean
success = False

//  To further clarify, see OAuth 2.0 Authorization Flow

Dim oauth2 As New Chilkat.OAuth2

//  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://github.com/login/oauth/authorize"
oauth2.TokenEndpoint = "https://github.com/login/oauth/access_token"

//  Replace with your actual Client ID
oauth2.ClientId = "CLIENT_ID"

//  This is for Require Proof Key for Code Exchange (PKCE)
//  See OAuth2 PKCE Explained
oauth2.CodeChallenge = True
oauth2.CodeChallengeMethod = "S256"

//  To force the OAuth consent screen to reappear (even if previously granted)
success = oauth2.AddAuthQueryParam("prompt","consent")

//  Begin the OAuth2 Authorization code flow.  This returns a URL that should be loaded in a browser.
Dim url As String
url = oauth2.StartAuth()
If (oauth2.LastMethodSuccess <> True) Then
    System.DebugLog(oauth2.LastErrorText)
    Return
End If

//  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) Then
    System.DebugLog(oauth2.LastErrorText)
    Return
End If

//  Wait for the user to approve or deny authorization in the browser.
Dim numMsWaited As Int32
numMsWaited = 0
While (numMsWaited < 90000) And (oauth2.AuthFlowState < 3)
    oauth2.SleepMs 100
    numMsWaited = numMsWaited + 100
Wend

//  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) Then
    success = oauth2.Cancel()
    System.DebugLog("No response from the browser!")
    Return
End If

//  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) Then
    System.DebugLog("OAuth2 failed to complete.")
    System.DebugLog(oauth2.FailureInfo)
    Return
End If

If (oauth2.AuthFlowState = 4) Then
    System.DebugLog("OAuth2 authorization was denied.")
    System.DebugLog(oauth2.AccessTokenResponse)
    Return
End If

If (oauth2.AuthFlowState <> 3) Then
    System.DebugLog("Unexpected AuthFlowState:" + Str(oauth2.AuthFlowState))
    Return
End If

System.DebugLog("OAuth2 authorization granted!")
System.DebugLog("Access Token = " + oauth2.AccessToken)