Initial QSfera import

Server/vendor/github.com/sercand/kuberesolver/v5/README.md

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+# kuberesolver
+
+A Grpc name resolver by using kubernetes API.
+It comes with a small ~250 LOC kubernetes client to find service endpoints. Therefore it won't bloat your binaries.
+
+
+### USAGE
+
+```go
+
+// Import the module
+import "github.com/sercand/kuberesolver/v5"
+	
+// Register kuberesolver to grpc before calling grpc.Dial
+kuberesolver.RegisterInCluster()
+
+// it is same as
+resolver.Register(kuberesolver.NewBuilder(nil /*custom kubernetes client*/ , "kubernetes"))
+
+// if schema is 'kubernetes' then grpc will use kuberesolver to resolve addresses
+cc, err := grpc.Dial("kubernetes:///service.namespace:portname", opts...)
+```
+
+An url can be one of the following, [grpc naming docs](https://github.com/grpc/grpc/blob/master/doc/naming.md)
+
+```
+kubernetes:///service-name:8080
+kubernetes:///service-name:portname
+kubernetes:///service-name.namespace:8080
+kubernetes:///service-name.namespace.svc.cluster_name
+kubernetes:///service-name.namespace.svc.cluster_name:8080
+
+kubernetes://namespace/service-name:8080
+kubernetes://service-name:8080/
+kubernetes://service-name.namespace:8080/
+kubernetes://service-name.namespace.svc.cluster_name
+kubernetes://service-name.namespace.svc.cluster_name:8080
+```
+_* Please note that the cluster_name is not used in resolving the endpoints of a Service. It is only there to support fully qualified service names, e.g._ `test.default.svc.cluster.local`.
+
+### Using alternative Schema
+
+Use `RegisterInClusterWithSchema(schema)` instead of `RegisterInCluster` on start.
+
+### Client Side Load Balancing
+
+You need to pass grpc.WithBalancerName option to grpc on dial: 
+
+```go
+grpc.DialContext(ctx,  "kubernetes:///service:grpc", grpc.WithBalancerName("round_robin"), grpc.WithInsecure())
+```
+This will create subconnections for each available service endpoints.
+
+### How is this different from dialing to `service.namespace:8080`
+
+Connecting to a service by dialing to `service.namespace:8080` uses DNS and it returns service stable IP. Therefore, gRPC doesn't know the endpoint IP addresses and it fails to reconnect to target services in case of failure.  
+
+Kuberesolver uses kubernetes API to get and watch service endpoint IP addresses. 
+Since it provides and updates all available service endpoints, together with a client-side balancer you can achive zero downtime deployments.
+
+### RBAC
+
+You need give `GET` and `WATCH` access to the `endpoints` if you are using RBAC in your cluster.
+
+
+### Using With TLS
+
+You need to a certificate with name `service-name.namespace` in order to connect with TLS to your services.