server: Fix panic in /health?bundle=true

The issue was that with bundles loaded from the file system we would
not initialize the mutex used for checking bundle status.

This fixes the initialization and prevents the error. Health status
works as expected now.

Fixes: open-policy-agent#1703
Signed-off-by: Patrick East <east.patrick@gmail.com>

server/server.go

@@ -107,7 +107,7 @@ type Server struct {
 	runtime           *ast.Term
 	httpListeners     []httpListener
 	bundleStatuses    map[string]*bundlePlugin.Status
-	bundleStatusMtx   *sync.RWMutex
+	bundleStatusMtx   sync.RWMutex
 	metrics           Metrics
 }
 
@@ -176,7 +176,6 @@ func (s *Server) Init(ctx context.Context) (*Server, error) {
 
 	bp := bundlePlugin.Lookup(s.manager)
 	if bp != nil {
-		s.bundleStatusMtx = new(sync.RWMutex)
 
 		// initialize statuses to empty defaults for server /health check
 		s.bundleStatuses = map[string]*bundlePlugin.Status{}

server/server_test.go

@@ -21,7 +21,6 @@ import (
 	"reflect"
 	"sort"
 	"strings"
-	"sync"
 	"testing"
 	"time"
 
@@ -81,7 +80,6 @@ func TestUnversionedGetHealthCheckBundleActivationSingle(t *testing.T) {
 	// Initialize the server as if a bundle plugin was
 	// configured on the manager.
 	f.server.manager.Register(pluginBundle.Name, &pluginBundle.Plugin{})
-	f.server.bundleStatusMtx = new(sync.RWMutex)
 	f.server.bundleStatuses = map[string]*pluginBundle.Status{
 		bundleName: &pluginBundle.Status{Name: bundleName},
 	}
@@ -106,6 +104,31 @@ func TestUnversionedGetHealthCheckBundleActivationSingle(t *testing.T) {
 	}
 }
 
+func TestUnversionedGetHealthCheckBundleActivationSingleLegacy(t *testing.T) {
+
+	// Initialize the server as if there is no bundle plugin
+
+	f := newFixture(t)
+
+	ctx := context.Background()
+
+	err := storage.Txn(ctx, f.server.store, storage.WriteParams, func(txn storage.Transaction) error {
+		return bundle.LegacyWriteManifestToStore(ctx, f.server.store, txn, bundle.Manifest{
+			Revision: "a",
+		})
+	})
+
+	if err != nil {
+		t.Fatalf("Unexpected error: %s", err)
+	}
+
+	// The heath check should now respond as healthy
+	req := newReqUnversioned(http.MethodGet, "/health?bundle=true", "")
+	if err := f.executeRequest(req, 200, `{}`); err != nil {
+		t.Fatal(err)
+	}
+}
+
 func TestUnversionedGetHealthCheckBundleActivationMulti(t *testing.T) {
 
 	f := newFixture(t)
@@ -118,7 +141,6 @@ func TestUnversionedGetHealthCheckBundleActivationMulti(t *testing.T) {
 		"b3": {Service: "s3", Resource: "bundle.tar.gz"},
 	}}, f.server.manager)
 	f.server.manager.Register(pluginBundle.Name, bp)
-	f.server.bundleStatusMtx = new(sync.RWMutex)
 	f.server.bundleStatuses = map[string]*pluginBundle.Status{
 		"b1": {Name: "b1"},
 		"b2": {Name: "b2"},
@@ -187,10 +209,6 @@ func TestInitWithBundlePlugin(t *testing.T) {
 		t.Error("server.hasBundle should be true")
 	}
 
-	if server.bundleStatusMtx == nil {
-		t.Error("server.bundleStatusMtx should be initialized")
-	}
-
 	isActivated := server.bundlesActivated()
 	if isActivated {
 		t.Error("bundle should not be initialized to activated status")
@@ -225,10 +243,6 @@ func TestInitWithBundlePluginMultiBundle(t *testing.T) {
 		t.Error("server.hasBundle should be true")
 	}
 
-	if server.bundleStatusMtx == nil {
-		t.Error("server.bundleStatusMtx should be initialized")
-	}
-
 	isActivated := server.bundlesActivated()
 	if isActivated {
 		t.Error("bundle should not be initialized to activated")
@@ -1662,7 +1676,6 @@ func TestDataProvenanceSingleBundle(t *testing.T) {
 	// Initialize as if a bundle plugin is running
 	bp := pluginBundle.New(&pluginBundle.Config{Name: "b1"}, f.server.manager)
 	f.server.manager.Register(pluginBundle.Name, bp)
-	f.server.bundleStatusMtx = new(sync.RWMutex)
 	f.server.bundleStatuses = map[string]*pluginBundle.Status{
 		"b1": {Name: "b1"},
 	}
@@ -1774,7 +1787,6 @@ func TestDataProvenanceMultiBundle(t *testing.T) {
 	}}, f.server.manager)
 	f.server.manager.Register(pluginBundle.Name, bp)
 
-	f.server.bundleStatusMtx = new(sync.RWMutex)
 	f.server.bundleStatuses = map[string]*pluginBundle.Status{
 		"b1": {Name: "b1"},
 		"b2": {Name: "b2"},