Hi, @thejeswar_reddy ,
It’s not going to be phased out. For over ten years they’d talked about it and every once in a while someone comes up to me panicing about deprecation.
Originally, they wanted to (long time ago) but they had no plan for accounting for the thousands of integrations out there that they would completely destroy, so it just sat as something to think about. Then, when they came out with the first version of Keap (before they were Infusionsoft), they talked about wanting to again, but still had no answer to the failing integrations issue. They were talking about getting rid of Infusionsoft (Keap Max Classic now) all together and the partners all said quite loudly ‘no don’t do that’. So they changed their minds and now we have all the versions of Keap we have.
So there isn’t any way for them to get rid of the api key method without destroying a ton of existing integrations which would result in a loss of a huge number of customers. They prefer for people to use REST/OAuth. If you’re building something for others to use and not just internally for your company, they want you to use REST/OAuth. But there are a ton of integrations and services out there using the api key for authentication and that’s not going to change.
You do not have to worry about it not functioning any time soon.