[LevelDB IndexedDB] Return empty rows instead of error when db or obj…

…ect store doesn't exist (#1830)

ee/indexeddb/indexeddb.go

@@ -11,6 +11,7 @@ import (
 	"path/filepath"
 
 	"github.com/kolide/goleveldb/leveldb"
+	leveldberrors "github.com/kolide/goleveldb/leveldb/errors"
 	"github.com/kolide/goleveldb/leveldb/opt"
 	"github.com/kolide/launcher/ee/agent"
 )
@@ -41,6 +42,8 @@ func QueryIndexeddbObjectStore(dbLocation string, dbName string, objectStoreName
 	// The copy was successful -- make sure we clean it up after we're done
 	defer os.RemoveAll(tempDbCopyLocation)
 
+	objs := make([]map[string][]byte, 0)
+
 	opts := &opt.Options{
 		Comparer:               indexeddbComparer,
 		DisableSeeksCompaction: true,               // no need to perform compaction
@@ -64,6 +67,10 @@ func QueryIndexeddbObjectStore(dbLocation string, dbName string, objectStoreName
 	}
 	databaseIdRaw, err := db.Get(databaseNameKey, nil)
 	if err != nil {
+		// If the database doesn't exist, return an empty list of objects
+		if errors.Is(err, leveldberrors.ErrNotFound) {
+			return objs, nil
+		}
 		return nil, fmt.Errorf("querying for database id: %w", err)
 	}
 	databaseId, _ := binary.Uvarint(databaseIdRaw)
@@ -88,14 +95,14 @@ func QueryIndexeddbObjectStore(dbLocation string, dbName string, objectStoreName
 	}
 
 	if objectStoreId == 0 {
-		return nil, errors.New("unable to get object store ID")
+		// If the object store doesn't exist, return an empty list of objects
+		return objs, nil
 	}
 
 	// Get the key prefix for all objects in this store.
 	keyPrefix := objectDataKeyPrefix(databaseId, objectStoreId)
 
 	// Now, we can read all records, keeping only the ones with our matching key prefix.
-	objs := make([]map[string][]byte, 0)
 	iter := db.NewIterator(nil, nil)
 	for iter.Next() {
 		key := iter.Key()

ee/katc/table_test.go

@@ -156,22 +156,40 @@ func TestQueryChromeIndexedDB(t *testing.T) {
 	// indexeddb_leveldb.go and the ee/indexeddb package.
 
 	for _, tt := range []struct {
+		testName     string
 		fileName     string
 		dbName       string
 		objStoreName string
 		expectedRows int
 		zipBytes     []byte
 	}{
 		{
+			testName:     "file__0.indexeddb.leveldb.zip",
 			fileName:     "file__0.indexeddb.leveldb.zip",
 			dbName:       "launchertestdb",
 			objStoreName: "launchertestobjstore",
 			expectedRows: 2,
 			zipBytes:     basicChromeIndexeddb,
 		},
+		{
+			testName:     "file__0.indexeddb.leveldb.zip -- db does not exist",
+			fileName:     "file__0.indexeddb.leveldb.zip",
+			dbName:       "not-the-correct-db-name",
+			objStoreName: "launchertestobjstore",
+			expectedRows: 0,
+			zipBytes:     basicChromeIndexeddb,
+		},
+		{
+			testName:     "file__0.indexeddb.leveldb.zip -- object store does not exist",
+			fileName:     "file__0.indexeddb.leveldb.zip",
+			dbName:       "launchertestdb",
+			objStoreName: "not-the-correct-obj-store-name",
+			expectedRows: 0,
+			zipBytes:     basicChromeIndexeddb,
+		},
 	} {
 		tt := tt
-		t.Run(tt.fileName, func(t *testing.T) {
+		t.Run(tt.testName, func(t *testing.T) {
 			t.Parallel()
 
 			// Write zip bytes to file