Reorganize scheduling plugins (kubernetes-sigs#837)

Author: liu-cong

cmd/epp/main.go

@@ -46,8 +46,8 @@ import (
 	"sigs.k8s.io/gateway-api-inference-extension/pkg/epp/scheduling"
 	"sigs.k8s.io/gateway-api-inference-extension/pkg/epp/scheduling/plugins"
 	"sigs.k8s.io/gateway-api-inference-extension/pkg/epp/scheduling/plugins/filter"
+	"sigs.k8s.io/gateway-api-inference-extension/pkg/epp/scheduling/plugins/multi/prefix"
 	"sigs.k8s.io/gateway-api-inference-extension/pkg/epp/scheduling/plugins/picker"
-	"sigs.k8s.io/gateway-api-inference-extension/pkg/epp/scheduling/plugins/prefix"
 	"sigs.k8s.io/gateway-api-inference-extension/pkg/epp/scheduling/plugins/scorer"
 	runserver "sigs.k8s.io/gateway-api-inference-extension/pkg/epp/server"
 	envutil "sigs.k8s.io/gateway-api-inference-extension/pkg/epp/util/env"

pkg/epp/scheduling/config.go

@@ -18,7 +18,7 @@ package scheduling
 
 import (
 	"sigs.k8s.io/gateway-api-inference-extension/pkg/epp/scheduling/plugins"
-	"sigs.k8s.io/gateway-api-inference-extension/pkg/epp/scheduling/plugins/prefix"
+	"sigs.k8s.io/gateway-api-inference-extension/pkg/epp/scheduling/plugins/multi/prefix"
 )
 
 // NewSchedulerConfig creates a new SchedulerConfig object with the given plugins.

pkg/epp/scheduling/plugins/README.md

@@ -0,0 +1,16 @@
+# Scheduling Plugins
+
+This package contains the scheduling plugin interface definitions and
+implementations.
+
+Plugins are organized by the following rule. Follow this rule when adding a new
+plugin.
+
+```
+plugins/
+|__ filter/(Plugins that only implement the Filter interface.)
+|__ scorer/ (Plugins that only implement the Scorer interface.)
+|__ picker/(Plugins that only implement the Picker interface.)
+|__ multi/ (Plugins that implement multiple plugin interfaces.)
+|____prefix/ (Prefix cache aware scheduling plugin.)
+```