simulate: decode zstd-compressed run summaries (#904)

* simulate: decode zstd-compressed run summaries

* simulate: protocol summary_zstd from merged main

* drop narration comment

* decode summary once per run update instead of memoizing globals

Author: theomonnom

cmd/lk/simulate.go

@@ -31,12 +31,14 @@ import (
 	"github.com/urfave/cli/v3"
 	"gopkg.in/yaml.v3"
 
+	"github.com/klauspost/compress/zstd"
 	"github.com/livekit/livekit-cli/v2/pkg/agentfs"
 	"github.com/livekit/livekit-cli/v2/pkg/config"
 	"github.com/livekit/livekit-cli/v2/pkg/util"
 	"github.com/livekit/protocol/livekit"
 	lksdk "github.com/livekit/server-sdk-go/v2"
 	"github.com/livekit/server-sdk-go/v2/pkg/cloudagents"
+	"google.golang.org/protobuf/proto"
 )
 
 func init() {
@@ -601,3 +603,23 @@ func simulationJobCounts(run *livekit.SimulationRun) (total, done, passed, faile
 	}
 	return
 }
+
+func decodeRunSummary(run *livekit.SimulationRun) *livekit.SimulationRunSummary {
+	if run == nil || len(run.SummaryZstd) == 0 {
+		return nil
+	}
+	dec, err := zstd.NewReader(nil)
+	if err != nil {
+		return nil
+	}
+	defer dec.Close()
+	raw, err := dec.DecodeAll(run.SummaryZstd, nil)
+	if err != nil {
+		return nil
+	}
+	summary := &livekit.SimulationRunSummary{}
+	if err := proto.Unmarshal(raw, summary); err != nil {
+		return nil
+	}
+	return summary
+}

cmd/lk/simulate_ci.go

@@ -205,6 +205,7 @@ func writeRunResults(w io.Writer, run *livekit.SimulationRun, ap *AgentProcess)
 	if run == nil {
 		return
 	}
+	summary := decodeRunSummary(run)
 
 	if run.Status == livekit.SimulationRun_STATUS_FAILED && len(run.Jobs) == 0 {
 		fmt.Fprintf(w, "✗ Simulation failed: %s\n", run.Error)
@@ -249,8 +250,8 @@ func writeRunResults(w io.Writer, run *livekit.SimulationRun, ap *AgentProcess)
 			}
 		}
 
-		if run.Summary != nil && run.Summary.ChatHistory != nil {
-			writeChatHistory(w, run.Summary.ChatHistory[job.Id])
+		if summary != nil && summary.ChatHistory != nil {
+			writeChatHistory(w, summary.ChatHistory[job.Id])
 		}
 
 		if ap != nil && job.RoomName != "" {
@@ -271,8 +272,8 @@ func writeRunResults(w io.Writer, run *livekit.SimulationRun, ap *AgentProcess)
 		}
 	}
 
-	if run.Summary != nil {
-		writeRunSummary(w, run)
+	if summary != nil {
+		writeRunSummary(w, run, summary)
 	} else {
 		msg := "The summary for this run is not available"
 		if run.Error != "" {
@@ -283,8 +284,7 @@ func writeRunResults(w io.Writer, run *livekit.SimulationRun, ap *AgentProcess)
 	}
 }
 
-func writeRunSummary(w io.Writer, run *livekit.SimulationRun) {
-	summary := run.Summary
+func writeRunSummary(w io.Writer, run *livekit.SimulationRun, summary *livekit.SimulationRunSummary) {
 	total, _, passed, failed := simulationJobCounts(run)
 
 	fmt.Fprintln(w)

cmd/lk/simulate_tui.go

@@ -40,8 +40,8 @@ func runSimulateTUI(config *simulateConfig) error {
 	_, runErr := p.Run()
 
 	if m.launcher != nil {
-    // A second ctrl+c during cleanup would kill the CLI and leak the worker
-    // (own process group, port stays bound); escalate to SIGKILL instead.
+		// A second ctrl+c during cleanup would kill the CLI and leak the worker
+		// (own process group, port stays bound); escalate to SIGKILL instead.
 		sigCh := make(chan os.Signal, 1)
 		signal.Notify(sigCh, os.Interrupt)
 		defer signal.Stop(sigCh)
@@ -157,6 +157,7 @@ type simulateModel struct {
 
 	// Run phase
 	run            *livekit.SimulationRun
+	summary        *livekit.SimulationRunSummary
 	runFinished    bool
 	brokenAgent    bool
 	numSimulations int32
@@ -362,6 +363,7 @@ func (m *simulateModel) runSetup() tea.Cmd {
 			m.err = err
 		}
 		m.run = run
+		m.summary = decodeRunSummary(run)
 		m.setupDone = true
 		return nil
 	}
@@ -575,6 +577,7 @@ func (m *simulateModel) Update(msg tea.Msg) (tea.Model, tea.Cmd) {
 	case simulationRunMsg:
 		if msg.err == nil && msg.run != nil {
 			m.run = msg.run
+			m.summary = decodeRunSummary(msg.run)
 			m.reporter.RunUpdate(msg.run, m.config.numSimulations)
 			if m.startTime.IsZero() && msg.run.Status == livekit.SimulationRun_STATUS_RUNNING {
 				m.startTime = time.Now()
@@ -1101,7 +1104,7 @@ func (m *simulateModel) viewRunning() string {
 
 		if m.run.Status == livekit.SimulationRun_STATUS_SUMMARIZING {
 			fmt.Fprintf(&b, "\n  %s %s  %s\n", yellowStyle().Render("⏺"), yellowStyle().Render("Generating summary..."), m.spinner())
-		} else if m.run.Summary != nil {
+		} else if m.summary != nil {
 			b.WriteString(m.renderSummary())
 		} else if isTerminalRunStatus(m.run.Status) {
 			msg := "The summary for this run is not available"
@@ -1553,7 +1556,7 @@ func (m *simulateModel) scrolledDetail() string {
 }
 
 func (m *simulateModel) renderSummary() string {
-	summary := m.run.Summary
+	summary := m.summary
 	if summary == nil {
 		return ""
 	}
@@ -1622,10 +1625,10 @@ func (m *simulateModel) renderSummary() string {
 }
 
 func (m *simulateModel) renderChatTranscript(jobID string) string {
-	if m.run.Summary == nil || m.run.Summary.ChatHistory == nil {
+	if m.summary == nil || m.summary.ChatHistory == nil {
 		return ""
 	}
-	chatCtx, ok := m.run.Summary.ChatHistory[jobID]
+	chatCtx, ok := m.summary.ChatHistory[jobID]
 	if !ok || chatCtx == nil || len(chatCtx.Items) == 0 {
 		return ""
 	}

go.mod

@@ -19,7 +19,8 @@ require (
 	github.com/google/go-containerregistry v0.20.7
 	github.com/google/go-querystring v1.2.0
 	github.com/joho/godotenv v1.5.1
-	github.com/livekit/protocol v1.49.1-0.20260707153508-a36bd7e4afe5
+	github.com/klauspost/compress v1.18.6
+	github.com/livekit/protocol v1.49.1-0.20260712215709-8847d7456816
 	github.com/livekit/server-sdk-go/v2 v2.17.0
 	github.com/mattn/go-isatty v0.0.22
 	github.com/moby/patternmatcher v0.6.1
@@ -155,7 +156,6 @@ require (
 	github.com/in-toto/attestation v1.1.2 // indirect
 	github.com/in-toto/in-toto-golang v0.11.0 // indirect
 	github.com/jxskiss/base62 v1.1.0 // indirect
-	github.com/klauspost/compress v1.18.6 // indirect
 	github.com/klauspost/cpuid/v2 v2.3.0 // indirect
 	github.com/klauspost/pgzip v1.2.6 // indirect
 	github.com/lithammer/shortuuid/v4 v4.2.0 // indirect

go.sum

@@ -357,8 +357,8 @@ github.com/livekit/mageutil v0.0.0-20250511045019-0f1ff63f7731 h1:9x+U2HGLrSw5AT
 github.com/livekit/mageutil v0.0.0-20250511045019-0f1ff63f7731/go.mod h1:Rs3MhFwutWhGwmY1VQsygw28z5bWcnEYmS1OG9OxjOQ=
 github.com/livekit/mediatransportutil v0.0.0-20260605212259-862d4a7bcb1e h1:SkgQRcG2VYEhh80Qb/zYZo8rWKJzNfJcfUQnXe6su2M=
 github.com/livekit/mediatransportutil v0.0.0-20260605212259-862d4a7bcb1e/go.mod h1:o8CFmAdrVwzJNOCsQCLUzXRjokkufNshnQHOe4fRaqU=
-github.com/livekit/protocol v1.49.1-0.20260707153508-a36bd7e4afe5 h1:6ItjuVJkxz/fpxz9eo4pt8FNtEoRSWUUSIZqGl4wOcE=
-github.com/livekit/protocol v1.49.1-0.20260707153508-a36bd7e4afe5/go.mod h1:jO+y05AU9Ec4JswDyuzKCZ4bhziOS0CzMqgnbj60Dzs=
+github.com/livekit/protocol v1.49.1-0.20260712215709-8847d7456816 h1:MDWDlH5dmcZY4OSljwE4e6B39libPQJIEmBRYaeGAn0=
+github.com/livekit/protocol v1.49.1-0.20260712215709-8847d7456816/go.mod h1:jO+y05AU9Ec4JswDyuzKCZ4bhziOS0CzMqgnbj60Dzs=
 github.com/livekit/psrpc v0.7.2 h1:6oZ+NODJ2pLyaT6VqDq1F4Qc/3TpDUSpyphj/P9MhQc=
 github.com/livekit/psrpc v0.7.2/go.mod h1:rAI+m2+/cb4x9RXhLRtUx5ZwdfjjXOl4zi46IjEetaw=
 github.com/livekit/server-sdk-go/v2 v2.17.0 h1:FzVQMoxHv0WIg164yGqSxLeV+h3aJomjAv1lFeR9MMw=