Replace explicit resampling config with policy based approach

Entire-Checkpoint: f69e38210bb1

internal/metricdispatch/resamplepolicy.go

@@ -0,0 +1,49 @@
+// Copyright (C) NHR@FAU, University Erlangen-Nuremberg.
+// All rights reserved. This file is part of cc-backend.
+// Use of this source code is governed by a MIT-style
+// license that can be found in the LICENSE file.
+package metricdispatch
+
+import "math"
+
+type ResamplePolicy string
+
+const (
+	ResamplePolicyLow    ResamplePolicy = "low"
+	ResamplePolicyMedium ResamplePolicy = "medium"
+	ResamplePolicyHigh   ResamplePolicy = "high"
+)
+
+// TargetPointsForPolicy returns the target number of data points for a given policy.
+func TargetPointsForPolicy(policy ResamplePolicy) int {
+	switch policy {
+	case ResamplePolicyLow:
+		return 200
+	case ResamplePolicyMedium:
+		return 500
+	case ResamplePolicyHigh:
+		return 1000
+	default:
+		return 0
+	}
+}
+
+// ComputeResolution computes the resampling resolution in seconds for a given
+// job duration, metric frequency, and target point count. Returns 0 if the
+// total number of data points is already at or below targetPoints (no resampling needed).
+func ComputeResolution(duration int64, frequency int64, targetPoints int) int {
+	if frequency <= 0 || targetPoints <= 0 || duration <= 0 {
+		return 0
+	}
+
+	totalPoints := duration / frequency
+	if totalPoints <= int64(targetPoints) {
+		return 0
+	}
+
+	targetRes := math.Ceil(float64(duration) / float64(targetPoints))
+	// Round up to nearest multiple of frequency
+	resolution := int(math.Ceil(targetRes/float64(frequency))) * int(frequency)
+
+	return resolution
+}

internal/metricdispatch/resamplepolicy_test.go

@@ -0,0 +1,68 @@
+// Copyright (C) NHR@FAU, University Erlangen-Nuremberg.
+// All rights reserved. This file is part of cc-backend.
+// Use of this source code is governed by a MIT-style
+// license that can be found in the LICENSE file.
+package metricdispatch
+
+import "testing"
+
+func TestTargetPointsForPolicy(t *testing.T) {
+	tests := []struct {
+		policy ResamplePolicy
+		want   int
+	}{
+		{ResamplePolicyLow, 200},
+		{ResamplePolicyMedium, 500},
+		{ResamplePolicyHigh, 1000},
+		{ResamplePolicy("unknown"), 0},
+		{ResamplePolicy(""), 0},
+	}
+
+	for _, tt := range tests {
+		if got := TargetPointsForPolicy(tt.policy); got != tt.want {
+			t.Errorf("TargetPointsForPolicy(%q) = %d, want %d", tt.policy, got, tt.want)
+		}
+	}
+}
+
+func TestComputeResolution(t *testing.T) {
+	tests := []struct {
+		name         string
+		duration     int64
+		frequency    int64
+		targetPoints int
+		want         int
+	}{
+		// 24h job, 60s frequency, 1440 total points
+		{"low_24h_60s", 86400, 60, 200, 480},
+		{"medium_24h_60s", 86400, 60, 500, 180},
+		{"high_24h_60s", 86400, 60, 1000, 120},
+
+		// 2h job, 60s frequency, 120 total points — no resampling needed
+		{"low_2h_60s", 7200, 60, 200, 0},
+		{"medium_2h_60s", 7200, 60, 500, 0},
+		{"high_2h_60s", 7200, 60, 1000, 0},
+
+		// Edge: zero/negative inputs
+		{"zero_duration", 0, 60, 200, 0},
+		{"zero_frequency", 86400, 0, 200, 0},
+		{"zero_target", 86400, 60, 0, 0},
+		{"negative_duration", -100, 60, 200, 0},
+
+		// 12h job, 30s frequency, 1440 total points
+		{"medium_12h_30s", 43200, 30, 500, 90},
+
+		// Exact fit: total points == target points
+		{"exact_fit", 12000, 60, 200, 0},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			got := ComputeResolution(tt.duration, tt.frequency, tt.targetPoints)
+			if got != tt.want {
+				t.Errorf("ComputeResolution(%d, %d, %d) = %d, want %d",
+					tt.duration, tt.frequency, tt.targetPoints, got, tt.want)
+			}
+		})
+	}
+}