Xbase++ Requires Chilkat v10.1.2+

Google OAuth2 Access Token

See more OAuth2 Examples

Demonstrates how to get a Google OAuth2 access token from a desktop application or script. Xbase++

LOCAL nSuccess
LOCAL oOauth2
LOCAL cUrl
LOCAL nNumMsWaited
LOCAL oSbJson

nSuccess := 0

//  To further clarify, see OAuth 2.0 Authorization Flow

oOauth2 := CreateObject("Chilkat.OAuth2")

//  For Google OAuth2, set the listen port equal to the port used
//  in the Authorized Redirect URL for the Client ID.
//  For example, in this case the Authorized Redirect URL would be http://localhost:55568/
//  Your app should choose a port not likely not used by another application.
oOauth2:ListenPort := 55568

oOauth2:AuthorizationEndpoint := "https://accounts.google.com/o/oauth2/v2/auth"
oOauth2:TokenEndpoint := "https://www.googleapis.com/oauth2/v4/token"

//  Replace this with your actual client ID.
oOauth2:ClientId := "GOOGLE-CLIENT-ID"

//  This is the scope for Google Drive.
//  See https://developers.google.com/identity/protocols/googlescopes
//  Add the scopes that you need.
oOauth2:Scope := "https://www.googleapis.com/auth/drive"

//  Begin the OAuth2 authorization code flow.  This returns a URL that should be loaded in a browser.
cUrl := oOauth2:StartAuth()
IF (oOauth2:LastMethodSuccess != 1)
    ? oOauth2:LastErrorText
    oOauth2:destroy()
    RETURN
ENDIF

//  Launch the default browser on the system and navigate to the url.
//  The LaunchBrowser method was added in Chilkat v10.1.2.
nSuccess := oOauth2:LaunchBrowser(cUrl)
IF (nSuccess == 0)
    ? oOauth2:LastErrorText
    oOauth2:destroy()
    RETURN
ENDIF

//  Wait for the interactive user to grant permission in the interactive browser session.
//  We'll wait for a max of 90 seconds.
nNumMsWaited := 0
DO WHILE (nNumMsWaited < 90000) .AND. (oOauth2:AuthFlowState < 3)
    oOauth2:SleepMs(100)
    nNumMsWaited := nNumMsWaited + 100
ENDDO

//  If there was no response from the browser within 90 seconds, then 
//  the AuthFlowState will be equal to 1 or 2.
//  1: Waiting for Redirect. The OAuth2 background thread is waiting to receive the redirect HTTP request from the browser.
//  2: Waiting for Final Response. The OAuth2 background thread is waiting for the final access token response.
//  In that case, cancel the background task started in the call to StartAuth.
IF (oOauth2:AuthFlowState < 3)
    oOauth2:Cancel()
    ? "No response from the browser!"
    oOauth2:destroy()
    RETURN
ENDIF

//  Check the AuthFlowState to see if authorization was granted, denied, or if some error occurred
//  The possible AuthFlowState values are:
//  3: Completed with Success. The OAuth2 flow has completed, the background thread exited, and the successful JSON response is available in AccessTokenResponse property.
//  4: Completed with Access Denied. The OAuth2 flow has completed, the background thread exited, and the error JSON is available in AccessTokenResponse property.
//  5: Failed Prior to Completion. The OAuth2 flow failed to complete, the background thread exited, and the error information is available in the FailureInfo property.
IF (oOauth2:AuthFlowState == 5)
    ? "OAuth2 failed to complete."
    ? oOauth2:FailureInfo
    oOauth2:destroy()
    RETURN
ENDIF

IF (oOauth2:AuthFlowState == 4)
    ? "OAuth2 authorization was denied."
    ? oOauth2:AccessTokenResponse
    oOauth2:destroy()
    RETURN
ENDIF

IF (oOauth2:AuthFlowState != 3)
    ? "Unexpected AuthFlowState:" + Str(oOauth2:AuthFlowState)
    oOauth2:destroy()
    RETURN
ENDIF

//  Save the full JSON access token response to a file.
oSbJson := CreateObject("Chilkat.StringBuilder")
oSbJson:Append(oOauth2:AccessTokenResponse)
oSbJson:WriteFile("qa_data/tokens/_googleDrive.json", "utf-8", 0)

//  The saved JSON response looks like this:

//  	{
//  	 "access_token": "ya39.Ci-XA_C5bGgRDC3UaD-h0_NeL-DVIQnI2gHtBBBHkZzrwlARkwX6R3O0PCDEzRlfaQ",
//  	 "token_type": "Bearer",
//  	 "expires_in": 3600,
//  	 "refresh_token": "1/r_2c_7jddspcdfesrrfKqfXtqo08D6Q-gUU0DsdfVMsx0c"
//  	}
//  
? "OAuth2 authorization granted!"
? "Access Token = " + oOauth2:AccessToken

//  Here is an example showing how to define your OAuth 2.0 Credential in the Google Cloud Console
//  Note: Even though your application is technically not a web app, you should still select "Web Application"
//  because the Redirect URI is going to http://localhost:55568/ where Chilkat will receive it in a background thread.

//  

oOauth2:destroy()
oSbJson:destroy()