From 36f618990f920cb426dc7944c71eac2cc3b81129 Mon Sep 17 00:00:00 2001
From: Niall D <4562759+driev@users.noreply.github.com>
Date: Wed, 18 Sep 2024 14:07:19 +0100
Subject: [PATCH] create a CDS cluster per model (#5916)

---
 scheduler/pkg/envoy/processor/hash.go         | 32 -------------------
 scheduler/pkg/envoy/processor/incremental.go  |  3 +-
 .../pkg/envoy/processor/incremental_test.go   |  8 ++---
 3 files changed, 5 insertions(+), 38 deletions(-)
 delete mode 100644 scheduler/pkg/envoy/processor/hash.go

diff --git a/scheduler/pkg/envoy/processor/hash.go b/scheduler/pkg/envoy/processor/hash.go
deleted file mode 100644
index b09725a524..0000000000
--- a/scheduler/pkg/envoy/processor/hash.go
+++ /dev/null
@@ -1,32 +0,0 @@
-/*
-Copyright (c) 2024 Seldon Technologies Ltd.
-
-Use of this software is governed by
-(1) the license included in the LICENSE file or
-(2) if the license included in the LICENSE file is the Business Source License 1.1,
-the Change License after the Change Date as each is defined in accordance with the LICENSE file.
-*/
-
-package processor
-
-import (
-	"bytes"
-	"crypto/sha256"
-	"encoding/base64"
-	"sort"
-	"strconv"
-)
-
-func computeHashKeyForList(list []int) string {
-	var buffer bytes.Buffer
-	sort.Ints(list)
-	for _, v := range list {
-		buffer.WriteString(
-			strconv.Itoa(v))
-		buffer.WriteString(",")
-	}
-	h := sha256.New()
-	_, _ = h.Write(buffer.Bytes())
-	b := h.Sum(nil)
-	return base64.StdEncoding.EncodeToString(b)
-}
diff --git a/scheduler/pkg/envoy/processor/incremental.go b/scheduler/pkg/envoy/processor/incremental.go
index ce90179824..fd167081c1 100644
--- a/scheduler/pkg/envoy/processor/incremental.go
+++ b/scheduler/pkg/envoy/processor/incremental.go
@@ -196,7 +196,6 @@ func (p *IncrementalProcessor) setListeners() error {
 // newSnapshotVersion increments the current snapshotVersion
 // and returns as a string.
 func (p *IncrementalProcessor) newSnapshotVersion() string {
-
 	// Reset the snapshotVersion if it ever hits max size.
 	if p.snapshotVersion == math.MaxInt64 {
 		p.snapshotVersion = 0
@@ -256,7 +255,7 @@ func (p *IncrementalProcessor) updateEnvoyForModelVersion(modelRouteName string,
 		return
 	}
 
-	clusterNameBase := server.Name + "_" + computeHashKeyForList(assignment)
+	clusterNameBase := modelVersion.GetMeta().GetName() + "_" + strconv.FormatInt(int64(modelVersion.GetVersion()), 10)
 	httpClusterName := clusterNameBase + "_http"
 	grpcClusterName := clusterNameBase + "_grpc"
 	p.xdsCache.AddCluster(httpClusterName, modelRouteName, modelVersion.GetModel().GetMeta().GetName(), modelVersion.GetVersion(), false)
diff --git a/scheduler/pkg/envoy/processor/incremental_test.go b/scheduler/pkg/envoy/processor/incremental_test.go
index 630039d750..575c38054d 100644
--- a/scheduler/pkg/envoy/processor/incremental_test.go
+++ b/scheduler/pkg/envoy/processor/incremental_test.go
@@ -229,7 +229,7 @@ func TestUpdateEnvoyForModelVersion(t *testing.T) {
 			},
 			traffic:          100,
 			expectedRoutes:   2,
-			expectedClusters: 2,
+			expectedClusters: 4,
 		},
 		{
 			name: "TwoRoutesDifferentClusters",
@@ -593,7 +593,7 @@ func TestEnvoySettings(t *testing.T) {
 				createTestModel("model3", "server", 1, []int{1}, 1, []store.ModelReplicaState{store.Available}),
 				createTestExperiment("exp", []string{"model1", "model2"}, getStrPtr("model1"), getStrPtr("model3")),
 			},
-			numExpectedClusters: 4,
+			numExpectedClusters: 6,
 			numExpectedRoutes:   4,
 			experimentActive:    true,
 			experimentExists:    true,
@@ -607,7 +607,7 @@ func TestEnvoySettings(t *testing.T) {
 				createTestModel("model3", "server", 1, []int{1}, 1, []store.ModelReplicaState{store.Available}),
 				createTestPipeline("pipe", []string{"model1", "model2", "model3"}, 1),
 			},
-			numExpectedClusters:  4,
+			numExpectedClusters:  6,
 			numExpectedRoutes:    3,
 			numExpectedPipelines: 1,
 		},
@@ -710,7 +710,7 @@ func TestRollingUpdate(t *testing.T) {
 				createTestModel("model", "server", 1, []int{0}, 1, []store.ModelReplicaState{store.Available}),
 				createTestModel("model", "server", 2, []int{0, 1}, 2, []store.ModelReplicaState{store.Available, store.Loading}),
 			},
-			numExpectedClusters: 2,
+			numExpectedClusters: 4,
 			numExpectedRoutes:   1,
 			numTrafficSplits:    map[string]int{"model": 2},
 		},