B4X Requires Chilkat v10.1.2+

Schwab OAuth2 in a Desktop App

See more Schwab Examples

Demonstrates how to get a Charles Schwab OAuth2 access token from a desktop application or script. B4X

Dim success As Boolean = False

'  To further clarify, see OAuth 2.0 Authorization Flow

'  This is the way to initially obtain the OAuth2 access token.  Afterwards it can be 
'  repeatedly refreshed without user interaction, as shown in this example: Refresh Schwab OAuth2 Access Token.

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/OAuth2.php"
oauth2.ListenPort = 3017

oauth2.AuthorizationEndpoint = "https://api.schwabapi.com/v1/oauth/authorize"
oauth2.TokenEndpoint = "https://api.schwabapi.com/v1/oauth/token"

'  Replace these with actual values.
oauth2.ClientId = "APP_KEY"
oauth2.ClientSecret = "APP_SECRET"
oauth2.UseBasicAuth = True
oauth2.CodeChallenge = False

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/schwab-access-token.json", "utf-8", False)

'  The full JSON received looks like this:
'  {
'    "expires_in": 3600,
'    "x_refresh_token_expires_in": 8726400,
'    "refresh_token": "L011546037639r ... 3vR2DrbOmg0Sdagw",
'    "access_token": "eyJlbmMiOiJBMTI4Q0 ... oETJEMbeggg",
'    "token_type": "bearer"
'  }

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