new version of kubernetes HPA (horizontal pod autoscaler)

Currently kubernetes has a mechanism to autoscale pods according to metrics, and the target resource (i.e. CPU) setted in the configuration file. The number of pods is updated based on the calculation, comparing the target resource with the metrics of the resource (see this link for more information https://kubernetes.io/docs/tasks/run-application/horizontal-pod-autoscale). In this project it is required to do a modification in the way the calculation is performed.
The following tasks are required to be completed:
1- Understand the HPA pod autoscaler source code
2- Modify the calculation, invoking a rest service that will give as response the number of pod that will be required to be running
3- Send the current CPU metrics and number of pods running currently, in the request of the rest service.
4-Take the response of the rest service and update the number of pods according to the number of pods given by the service.