Add knob to tweak _busy_timeout

In SQLite3 we may need to set a busy_timeout in the case of instances
with high load. This change adds a knob that allows users to set a
timeout if a database is locked for writing by another routine.

Signed-off-by: Gabriel Adrian Samfira <[email protected]>

Author: gabriel-samfira

config/config.go

@@ -551,7 +551,8 @@ func (d *Database) Validate() error {
 
 // SQLite is the config entry for the sqlite3 section
 type SQLite struct {
-	DBFile string `toml:"db_file" json:"db-file"`
+	DBFile             string `toml:"db_file" json:"db-file"`
+	BusyTimeoutSeconds int    `toml:"busy_timeout_seconds" json:"busy-timeout-seconds"`
 }
 
 func (s *SQLite) Validate() error {
@@ -571,7 +572,12 @@ func (s *SQLite) Validate() error {
 }
 
 func (s *SQLite) ConnectionString() (string, error) {
-	return fmt.Sprintf("%s?_journal_mode=WAL&_foreign_keys=ON", s.DBFile), nil
+	connectionString := fmt.Sprintf("%s?_journal_mode=WAL&_foreign_keys=ON", s.DBFile)
+	if s.BusyTimeoutSeconds > 0 {
+		timeout := s.BusyTimeoutSeconds * 1000
+		connectionString = fmt.Sprintf("%s&_busy_timeout=%d", connectionString, timeout)
+	}
+	return connectionString, nil
 }
 
 // MySQL is the config entry for the mysql section

config/config_test.go

@@ -389,6 +389,12 @@ func TestGormParams(t *testing.T) {
 	require.Equal(t, SQLiteBackend, dbType)
 	require.Equal(t, filepath.Join(dir, "garm.db?_journal_mode=WAL&_foreign_keys=ON"), uri)
 
+	cfg.SQLite.BusyTimeoutSeconds = 5
+	dbType, uri, err = cfg.GormParams()
+	require.Nil(t, err)
+	require.Equal(t, SQLiteBackend, dbType)
+	require.Equal(t, filepath.Join(dir, "garm.db?_journal_mode=WAL&_foreign_keys=ON&_busy_timeout=5000"), uri)
+
 	cfg.DbBackend = MySQLBackend
 	cfg.MySQL = getMySQLDefaultConfig()
 	cfg.SQLite = SQLite{}

testdata/config.toml

@@ -97,6 +97,11 @@ time_to_live = "8760h"
   [database.sqlite3]
     # Path on disk to the sqlite3 database file.
     db_file = "/etc/garm/garm.db"
+    # busy_timeout_seconds is an optional parameter that will set the
+    # sqlite3_busy_timeout to the specified value. This is useful when
+    # GARM may be under heavy load and the database is locked by some
+    # other go routine. The default value is 0.
+    busy_timeout_seconds = 5
 
 # Currently, providers are defined statically in the config. This is due to the fact
 # that we have not yet added support for storing secrets in something like Barbican