refactor code structure (#1738)

pkg/simple/client/monitoring/prometheus.go

@@ -0,0 +1,31 @@
+package monitoring
+
+import (
+    "net/http"
+    "time"
+)
+
+// prometheus implements monitoring interface backed by Prometheus
+type prometheus struct {
+    options *Options
+    client            *http.Client
+}
+
+func NewPrometheus(options *Options) Interface {
+    return &prometheus{
+        options:options,
+        client: &http.Client{ Timeout: 10 * time.Second },
+    }
+}
+
+func (p prometheus) GetClusterMetrics(query ClusterQuery) ClusterMetrics {
+    panic("implement me")
+}
+
+func (p prometheus) GetWorkspaceMetrics(query WorkspaceQuery) WorkspaceMetrics {
+    panic("implement me")
+}
+
+func (p prometheus) GetNamespaceMetrics(query NamespaceQuery) NamespaceMetrics {
+    panic("implement me")
+}