test(agentcompat): add exact stress scenario

Co-authored-by: naiba/CloudCode <hi+cloudcode@nai.ba>

integration/agentcompat/internal/scenario/stress_soak.go

@@ -0,0 +1,88 @@
+//go:build linux
+
+package scenario
+
+import (
+	"errors"
+	"fmt"
+
+	"github.com/nezhahq/nezha/integration/agentcompat/internal/contract"
+)
+
+var ErrStressSoakTrend = errors.New("stress soak RSS increases strictly across all iterations")
+
+type StressRSSSeries struct {
+	Process     StressProcessIdentity `json:"process"`
+	EndRSSBytes [3]uint64             `json:"end_rss_bytes"`
+}
+
+type StressSoakTrendEvidence struct {
+	Series []StressRSSSeries `json:"series"`
+}
+
+func ValidateStressSoakTrend(evidence StressSoakTrendEvidence) error {
+	if len(evidence.Series) == 0 {
+		return errors.New("stress soak RSS series are empty")
+	}
+	seen := make(map[string]struct{}, len(evidence.Series))
+	for _, series := range evidence.Series {
+		key := series.Process.key()
+		if series.Process.PID < 1 || key == ":0" || (series.Process.Kind == StressProcessAgent && series.Process.Agent.Int() < 1) {
+			return fmt.Errorf("process=%s: %w", key, ErrStressIdentity)
+		}
+		if _, duplicate := seen[key]; duplicate {
+			return fmt.Errorf("duplicate process=%s: %w", key, ErrStressIdentity)
+		}
+		seen[key] = struct{}{}
+		values := series.EndRSSBytes
+		if values[0] < values[1] && values[1] < values[2] {
+			return fmt.Errorf("process=%s RSS=%v: %w", key, values, ErrStressSoakTrend)
+		}
+	}
+	return nil
+}
+
+func ValidateStressSoakTrendForProfile(profile contract.Profile, evidence StressSoakTrendEvidence) error {
+	want := profile.AgentCount() + 1
+	if len(evidence.Series) != want {
+		return fmt.Errorf("soak series=%d want=%d: %w", len(evidence.Series), want, ErrStressIdentity)
+	}
+	seenDashboard := 0
+	seenAgents := make(map[int]struct{}, profile.AgentCount())
+	for _, series := range evidence.Series {
+		if err := validateStressSoakSeries(series); err != nil {
+			return err
+		}
+		switch series.Process.Kind {
+		case StressProcessDashboard:
+			seenDashboard++
+		case StressProcessAgent:
+			ordinal := series.Process.Agent.Int()
+			if ordinal < 1 || ordinal > profile.AgentCount() {
+				return fmt.Errorf("unknown agent ordinal=%d: %w", ordinal, ErrStressIdentity)
+			}
+			if _, duplicate := seenAgents[ordinal]; duplicate {
+				return fmt.Errorf("duplicate agent ordinal=%d: %w", ordinal, ErrStressIdentity)
+			}
+			seenAgents[ordinal] = struct{}{}
+		default:
+			return fmt.Errorf("unknown process kind=%q: %w", series.Process.Kind, ErrStressIdentity)
+		}
+	}
+	if seenDashboard != 1 || len(seenAgents) != profile.AgentCount() {
+		return fmt.Errorf("dashboard=%d agents=%d: %w", seenDashboard, len(seenAgents), ErrStressIdentity)
+	}
+	return nil
+}
+
+func validateStressSoakSeries(series StressRSSSeries) error {
+	key := series.Process.key()
+	if series.Process.PID < 1 || key == ":0" || (series.Process.Kind == StressProcessAgent && series.Process.Agent.Int() < 1) {
+		return fmt.Errorf("process=%s: %w", key, ErrStressIdentity)
+	}
+	values := series.EndRSSBytes
+	if values[0] < values[1] && values[1] < values[2] {
+		return fmt.Errorf("process=%s RSS=%v: %w", key, values, ErrStressSoakTrend)
+	}
+	return nil
+}