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CkPython Requires Chilkat v10.1.2+

Get GMail SMTP OAuth2 Access Token for Desktop App

See more OAuth2 Examples

This example show how to obtain a Gmail SMTP OAuth2 access token from a desktop application or script, enabling the use of XOAUTH2 authentication.

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CkPython
import sys
import chilkat

success = False

#  To further clarify, see OAuth 2.0 Authorization Flow

oauth2 = chilkat.CkOAuth2()

#  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 any other application.
oauth2.put_ListenPort(55568)

oauth2.put_AuthorizationEndpoint("https://accounts.google.com/o/oauth2/v2/auth")
oauth2.put_TokenEndpoint("https://www.googleapis.com/oauth2/v4/token")

#  Replace these with actual values.
oauth2.put_ClientId("GOOGLE-CLIENT-ID")
oauth2.put_ClientSecret("GOOGLE-CLIENT-SECRET")

#  To use Gmail's OAuth2 for sending emails via the SMTP protocol, you need to request the https://mail.google.com/ scope. 
#  See About GMail SMTP OAuth2 Scopes
oauth2.put_Scope("https://mail.google.com/")

#  Begin the OAuth2 Authorization code flow.  This returns a URL that should be loaded in a browser.
url = oauth2.startAuth()
if (oauth2.get_LastMethodSuccess() != True):
    print(oauth2.lastErrorText())
    sys.exit()

#  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):
    print(oauth2.lastErrorText())
    sys.exit()

#  Wait for the user to approve or deny authorization in the browser.
numMsWaited = 0
while (numMsWaited < 90000) and (oauth2.get_AuthFlowState() < 3) :
    oauth2.SleepMs(100)
    numMsWaited = numMsWaited + 100

#  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.get_AuthFlowState() < 3):
    oauth2.Cancel()
    print("No response from the browser!")
    sys.exit()

#  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.get_AuthFlowState() == 5):
    print("OAuth2 failed to complete.")
    print(oauth2.failureInfo())
    sys.exit()

if (oauth2.get_AuthFlowState() == 4):
    print("OAuth2 authorization was denied.")
    print(oauth2.accessTokenResponse())
    sys.exit()

if (oauth2.get_AuthFlowState() != 3):
    print("Unexpected AuthFlowState:" + str(oauth2.get_AuthFlowState()))
    sys.exit()

#  Save the full JSON access token response to a file.
sbJson = chilkat.CkStringBuilder()
sbJson.Append(oauth2.accessTokenResponse())
sbJson.WriteFile("qa_data/tokens/_gmailSmtp.json","utf-8",False)

#  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"
#  	}
#  
print("OAuth2 authorization granted!")
print("Access Token = " + oauth2.accessToken())