BUG#35349093: Compression doesn't work with C extension API

Compression is not enabled when using the C API implementation directly
with the connection option `compress=True`.

This patch fixes this issue by adding CLIENT_COMPRESS to client flags.

Thank you for your contribution.

Change-Id: If1fdc1b9316e9bf55416d19b594c8671d3d4d082

Author: nmariz

CHANGES.txt

@@ -13,6 +13,7 @@ v8.1.0
 
 - WL#15630: Remove Python 3.7 support
 - WL#15591: Improve the network module
+- BUG#35349093: Compression doesn't work with C extension API
 - BUG#35338384: PIP installs incompatible Connector/Python packages
 - BUG#35318413: Fix charset mapping for MySQL 8.1.0
 - BUG#35212199: Check for identifier quotes in the database name

lib/mysql/connector/connection_cext.py

@@ -243,7 +243,7 @@ def _open_connection(self) -> None:
             "port": self._port,
             "client_flags": self._client_flags,
             "unix_socket": self._unix_socket,
-            "compress": self.isset_client_flag(ClientFlag.COMPRESS),
+            "compress": self._compress,
             "ssl_disabled": True,
             "conn_attrs": self._conn_attrs,
             "local_infile": self._allow_local_infile,

src/mysql_capi.c

@@ -1206,6 +1206,10 @@ MySQL_connect(MySQL *self, PyObject *args, PyObject *kwds)
         client_flags = client_flags & ~CLIENT_LOCAL_FILES;
     }
 
+    if (compress != NULL && (PyBool_Check(compress) && compress == Py_True)) {
+        client_flags |= CLIENT_COMPRESS;
+    }
+
 #ifdef MS_WINDOWS
     if (NULL == host) {
         // if host is NULL, we try with named pipe

tests/test_bugs.py

@@ -83,11 +83,14 @@
 from . import check_tls_versions_support
 
 try:
+    from _mysql_connector import MySQL
+
     from mysql.connector.connection_cext import CMySQLConnection, MySQLInterfaceError
 except ImportError:
     # Test without C Extension
     CMySQLConnection = None
     MySQLInterfaceError = None
+    MySQL = None
 
 ERR_NO_CEXT = "C Extension not available"
 
@@ -7523,3 +7526,64 @@ def test_connect_database_name(self):
         config["database"] = self.database
         with self.cnx.__class__(**config) as cnx:
             self.assertTrue(cnx.is_connected())
+
+
+class BugOra35349093(tests.MySQLConnectorTests):
+    """BUG#35349093: Compression doesn't work with C extension API
+
+    Compression is not enabled when using the C API implementation directly
+    with the connection option `compress=True`.
+
+    This patch fixes this issue by adding CLIENT_COMPRESS to client flags.
+
+    Thank you for your contribution.
+    """
+
+    def _get_compression_status(self):
+        with self.cnx.cursor() as cur:
+            cur.execute("SHOW SESSION STATUS LIKE 'Compression'")
+            return cur.fetchone()
+
+    @staticmethod
+    def _test_compression_status_cext(compress):
+        config = tests.get_mysql_config()
+        del config["connection_timeout"]
+        config["compress"] = compress
+        cnx = MySQL()
+        cnx.connect(**config)
+        cnx.query("SHOW SESSION STATUS LIKE 'Compression'")
+        res = cnx.fetch_row()
+        cnx.close()
+        return res
+
+    @foreach_cnx()
+    def test_set_compress_default(self):
+        """Test default `compress` option."""
+        res = self._get_compression_status()
+        self.assertEqual(res, ("Compression", "OFF"))
+
+    @cnx_config(compress=False)
+    @foreach_cnx()
+    def test_set_compress_false(self):
+        """Test setting `compress=False`."""
+        res = self._get_compression_status()
+        self.assertEqual(res, ("Compression", "OFF"))
+
+    @cnx_config(compress=True)
+    @foreach_cnx()
+    def test_set_compress_true(self):
+        """Test setting `compress=True`."""
+        res = self._get_compression_status()
+        self.assertEqual(res, ("Compression", "ON"))
+
+    @unittest.skipIf(not CMySQLConnection, ERR_NO_CEXT)
+    def test_set_compress_cext_true(self):
+        """Test setting `compress=True` in the C extension directly."""
+        res = self._test_compression_status_cext(True)
+        self.assertEqual(res, ("Compression", "ON"))
+
+    @unittest.skipIf(not CMySQLConnection, ERR_NO_CEXT)
+    def test_set_compress_cext_false(self):
+        """Test setting `compress=False` in the C extension directly."""
+        res = self._test_compression_status_cext(False)
+        self.assertEqual(res, ("Compression", "OFF"))