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B4X Requires Chilkat v10.1.2+

Yahoo Mail OAuth2 Access Token for Desktop App

See more Yahoo Mail Examples

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

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B4X
Dim success As Boolean = False

'  First, you must define your app in Yahoo Developer (https://developer.yahoo.com/apps/) like this:

'  image

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

Dim oauth2 As ChilkatOAuth2
oauth2.Initialize("oauth2")

'  Your applicaton must use your own public web server as an intermediate
'  to receive and forward the redirect to localhost.
'  See Using Your Web Server as an Intermediary for OAuth2 Redirect to localhost
oauth2.AppCallbackUrl = "https://yourwebserver.com/oauth_redirect"
oauth2.ListenPort = 3017

oauth2.AuthorizationEndpoint = "https://api.login.yahoo.com/oauth2/request_auth"
oauth2.TokenEndpoint = "https://api.login.yahoo.com/oauth2/get_token"

'  Replace these with actual values.
oauth2.ClientId = "CLIENT_ID"
oauth2.ClientSecret = "CLIENT_SECRET"

'  Do not send the "scope" query param for Yahoo OAuth2.
oauth2.UncommonOptions = "NO_OAUTH2_SCOPE"

'  Begin the OAuth2 Authorization code flow.  This returns a URL that should be loaded in a browser.
Dim url As String = oauth2.StartAuth
If oauth2.LastMethodSuccess = False Then
    Log(oauth2.LastErrorText)
    Return
End If


Log("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 Then
    Log(oauth2.LastErrorText)
    Return
End If


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

'  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
    oauth2.Cancel
    Log("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
    Log("OAuth2 failed to complete.")
    Log(oauth2.FailureInfo)
    Return
End If


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


If oauth2.AuthFlowState <> 3 Then
    Log("Unexpected AuthFlowState:" & oauth2.AuthFlowState)
    Return
End If


'  Save the full JSON access token response to a file.
Dim sbJson As ChilkatStringBuilder
sbJson.Initialize
sbJson.Append(oauth2.AccessTokenResponse)
sbJson.WriteFile("qa_data/tokens/yahooMail.json", "utf-8", False)

'  The saved JSON response looks like this:

'  {
'    "access_token": "kCVQdnOdul...LHucA--",
'    "refresh_token": "AIenVXETSo0jklFBVkPS8vVm8E.Ej9ToRG.xDbDYmZ65WIs5t6CZhDrD",
'    "expires_in": 3600,
'    "token_type": "bearer",
'    "xoauth_yahoo_guid": "HGDQCVF5JB4YDOWHITQJFBHCWA"
'  }

Log("OAuth2 authorization granted!")
Log("Access Token: " & oauth2.AccessToken)