Visual FoxPro

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. Visual FoxPro

LOCAL lnSuccess
LOCAL loOauth2
LOCAL lcUrl
LOCAL lnNumMsWaited
LOCAL loSbJson

lnSuccess = 0

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

* 

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

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/oauth_redirect"
loOauth2.ListenPort = 3017

loOauth2.AuthorizationEndpoint = "https://api.login.yahoo.com/oauth2/request_auth"
loOauth2.TokenEndpoint = "https://api.login.yahoo.com/oauth2/get_token"

* Replace these with actual values.
loOauth2.ClientId = "CLIENT_ID"
loOauth2.ClientSecret = "CLIENT_SECRET"

* Do not send the "scope" query param for Yahoo OAuth2.
loOauth2.UncommonOptions = "NO_OAUTH2_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/yahooMail.json","utf-8",0)

* 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"
* }

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

RELEASE loOauth2
RELEASE loSbJson