Draft set session command test

database/set_mysql_session_vars_test.go

@@ -0,0 +1,63 @@
+package database
+
+import (
+"context"
+"database/sql/driver"
+"github.com/go-sql-driver/mysql"
+"github.com/jmoiron/sqlx"
+"github.com/stretchr/testify/assert"
+"github.com/stretchr/testify/require"
+"testing"
+)
+
+func TestSetMysqlSessionVars(t *testing.T) {
+	vars := map[string][]struct {
+		name   string
+		value  any
+		expect error
+	}{
+		"UnknownVariables": {
+			// MySQL single nodes do not recognise the "wsrep_sync_wait" system variable, but MariaDB does!
+			{name: "wsrep_sync_wait", value: int64(15)}, // MySQL unknown sys var | MariaDB succeeds
+			{name: "wsrep_sync_wait", value: int64(7)},  // MySQL unknown sys var | MariaDB succeeds
+			// Just some random unknown system variables :-)
+			{name: "Icinga", value: "Icinga"},     // unknown sys var
+			{name: "IcingaDB", value: "IcingaDB"}, // unknown sys var
+		},
+		"VariablesWithCorrectValue": { // Setting system variables known by MySQL/MariaDB to a valid value
+			{name: "transaction_isolation", value: "READ-UNCOMMITTED"},
+			{name: "explain_format", value: "TRADITIONAL"},
+			{name: "explain_format", value: "JSON"},
+			{name: "completion_type", value: int64(1) /** CHAIN */},
+			{name: "default_week_format", value: int64(7)},
+		},
+		"VariablesWithInvalidValues": { // System variables set to an invalid value
+			{name: "transaction_isolation", value: "REPEATABLE-WRITE", expect: &mysql.MySQLError{Number: 1231}},
+			{name: "completion_type", value: int64(-10), expect: &mysql.MySQLError{Number: 1231}}, // Min valid val 0
+			{name: "completion_type", value: int64(10), expect: &mysql.MySQLError{Number: 1231}},  // Max valid val 2
+			{name: "explain_format", value: "IcingaDB", expect: &mysql.MySQLError{Number: 1231}},
+		},
+	}
+
+	rdb := it.MysqlDatabase()
+	db, err := sqlx.Open(rdb.Driver(), rdb.DSN())
+	require.NoError(t, err, "opening MySQL/MariaDB database should not fail")
+
+	ctx := context.Background()
+	for name, vs := range vars {
+		t.Run(name, func(t *testing.T) {
+			for _, v := range vs {
+				conn, err := db.DB.Conn(ctx)
+				assert.NoError(t, err, "connecting to MySQL/MariaDB database should not fail")
+
+				err = conn.Raw(func(conn any) error {
+					return setSessionVariableIfExists(ctx, conn.(driver.Conn), v.name, v.value)
+				})
+
+				assert.ErrorIsf(t, err, v.expect, "setting %q variable to '%v' returns unexpected result", v.name, v.value)
+				assert.NoError(t, conn.Close(), "closing MySQL/MariaDB connection should not fail")
+			}
+		})
+	}
+}
+