Visual FoxPro

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. Visual FoxPro

LOCAL lnSuccess
LOCAL loOauth2
LOCAL lcUrl
LOCAL lnNumMsWaited
LOCAL loSbJson

lnSuccess = 0

* 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.

loOauth2 = CreateObject('Chilkat.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

loOauth2.AppCallbackUrl = "https://yourwebserver.com/OAuth2.php"
loOauth2.ListenPort = 3017

loOauth2.AuthorizationEndpoint = "https://api.schwabapi.com/v1/oauth/authorize"
loOauth2.TokenEndpoint = "https://api.schwabapi.com/v1/oauth/token"

* Replace these with actual values.
loOauth2.ClientId = "APP_KEY"
loOauth2.ClientSecret = "APP_SECRET"
loOauth2.UseBasicAuth = 1
loOauth2.CodeChallenge = 0

loOauth2.Scope = ""

* Begin the OAuth2 Authorization code flow.  This returns a URL that should be loaded in a browser.
lcUrl = loOauth2.StartAuth()
IF (loOauth2.LastMethodSuccess = 0) THEN
    ? loOauth2.LastErrorText
    RELEASE loOauth2
    CANCEL
ENDIF

? "url = " + lcUrl

* Launch the default browser on the system and navigate to the url.
* The LaunchBrowser method was added in Chilkat v10.1.2.
lnSuccess = loOauth2.LaunchBrowser(lcUrl)
IF (lnSuccess = 0) THEN
    ? loOauth2.LastErrorText
    RELEASE loOauth2
    CANCEL
ENDIF

* Wait for the user to approve or deny authorization in the browser.
lnNumMsWaited = 0
DO WHILE (lnNumMsWaited < 90000) AND (loOauth2.AuthFlowState < 3)
    loOauth2.SleepMs(100)
    lnNumMsWaited = lnNumMsWaited + 100
ENDDO

* 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 (loOauth2.AuthFlowState < 3) THEN
    loOauth2.Cancel()
    ? "No response from the browser!"
    RELEASE loOauth2
    CANCEL
ENDIF

* 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 (loOauth2.AuthFlowState = 5) THEN
    ? "OAuth2 failed to complete."
    ? loOauth2.FailureInfo
    RELEASE loOauth2
    CANCEL
ENDIF

IF (loOauth2.AuthFlowState = 4) THEN
    ? "OAuth2 authorization was denied."
    ? loOauth2.AccessTokenResponse
    RELEASE loOauth2
    CANCEL
ENDIF

IF (loOauth2.AuthFlowState <> 3) THEN
    ? "Unexpected AuthFlowState:" + STR(loOauth2.AuthFlowState)
    RELEASE loOauth2
    CANCEL
ENDIF

* Save the full JSON access token response to a file.
loSbJson = CreateObject('Chilkat.StringBuilder')
loSbJson.Append(loOauth2.AccessTokenResponse)
loSbJson.WriteFile("qa_data/tokens/schwab-access-token.json","utf-8",0)

* 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"
* }

? "OAuth2 authorization granted!"
? "Access Token = " + loOauth2.AccessToken

RELEASE loOauth2
RELEASE loSbJson