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CkPython

Automatically Refresh Token for 401 Unauthorized

See more Google Calendar Examples

Demonstrates how to automatically refresh an access token (without user interaction) when the token expires and a 401 Unauthorized response is received.

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CkPython
import sys
import chilkat

success = False

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

tokenFilePath = "qa_data/tokens/googleCalendar.json"

# Get our current access token.
jsonToken = chilkat.CkJsonObject()
success = jsonToken.LoadFile(tokenFilePath)
if (jsonToken.HasMember("access_token") == False):
    print("No access token found.")
    sys.exit()

http = chilkat.CkHttp()
http.put_AuthToken(jsonToken.stringOf("access_token"))

jsonResponse = http.quickGetStr("https://www.googleapis.com/calendar/v3/users/me/calendarList")
if (http.get_LastMethodSuccess() != True):

    if (http.get_LastStatus() != 401):
        print(http.lastErrorText())
        print("----")
        print(http.lastResponseBody())
        sys.exit()

    # The access token must've expired. 
    # Refresh the access token and then retry the request.
    oauth2 = chilkat.CkOAuth2()

    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")

    # Get the "refresh_token"
    oauth2.put_RefreshToken(jsonToken.stringOf("refresh_token"))

    # Send the HTTP POST to refresh the access token..
    success = oauth2.RefreshAccessToken()
    if (success != True):
        print(oauth2.lastErrorText())
        sys.exit()

    # The response contains a new access token, but we must keep
    # our existing refresh token for when we need to refresh again in the future.
    jsonToken.UpdateString("access_token",oauth2.accessToken())

    # Save the new JSON access token response to a file.
    sbJson = chilkat.CkStringBuilder()
    jsonToken.put_EmitCompact(False)
    jsonToken.EmitSb(sbJson)
    sbJson.WriteFile(tokenFilePath,"utf-8",False)

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

    # re-try the original request.
    http.put_AuthToken(oauth2.accessToken())
    jsonResponse = http.quickGetStr("https://www.googleapis.com/calendar/v3/users/me/calendarList")
    if (http.get_LastMethodSuccess() != True):
        print(http.lastErrorText())
        sys.exit()

print(jsonResponse)
print("-----------------------------")