Database Operations for Existing Database Cluster - Restart DB Cluster

The problem: There are several reasons why a customer may want to restart a database server instance.  For example, they are seeing issues with an instance and want to restart the database instance to see if that will help resolve their issue. 

User Story: As an Admin, I want to be able to log into the Percona Enterprise Platform, select the existing database cluster, and execute restart action 

After this  Percona Enterprise Platform should restart the selected database cluster member instances. Because of Technical limitation, this must be a rolling restart for all DB instances

The status of the DB cluster should be telling the "restarting" when the action executed. 

UI: 

An additional action in DB Cluster menu  = "Restart"

Suggested implementation:

1. Define restart endpoint in pmm API to communicate UI -> pmm-managed.

2. Define restart endpoint in dbaas-api to communicate pmm-managed ->  dbaas-controller.

3. Implement endpoint to receive type (PXC Cluster or PSMDB Cluster) and name of DBaaS in pmm-managed from UI.

4. Implement endpoint in dbaas-controller to restart DB Cluster where execute  

5. pmm-managed calls dbaas-contoller to restart DB cluster.

How to test/demonstrate:

(For API test please use attached swagger.json )

1. Create a DB cluster;

2. Wait for the cluster to be active;

3. Create table/collection in the cluster:

 remember Uptime value Uptime: 13 min 59 

3. Select restart action in the cluster;

4. Check that the cluster gets the status "Pending";

5. Wait for the cluster to be active again.

6. Check that inserted data is present and uptime value decreased Uptime: 5 min 16.