The Run Extract Refresh Task has been added in API 2.7 version, this version is available with tableau 10.4.
You can find the more details in below link.
Actually i am also trying to implement the same.
Thanks Surendhar, Tableau support confirmed the same too. I would try this out once we upgrade our server.
what were you trying to achieve here. I am looking for running Tableau extract refresh only when my database refresh finishes. it means tableau refresh is not based on time rather it is based on completion of backend database refresh.
Were you trying to achieve same functionality?