Support [clickhouse-driver 0.2.6](https://github.com/mymarilyn/clickhouse-driver) #14, drop support for python3.6.

Author: jayvynl

CHANGELOG.md

@@ -1,3 +1,10 @@
+### 1.0.3
+- Fix reading settings in explain, pull request [#13](https://github.com/jayvynl/django-clickhouse-backend/pull/13) by [mahdi-jfri](https://github.com/mahdi-jfri).
+- Add toYYYYMM[DD[hhmmss]] functions.
+- Fix str(queryset.query) when default database is not clickhouse.
+- Fix [bug when save django model instance](https://github.com/jayvynl/django-clickhouse-backend/issues/9).
+- Support [clickhouse-driver 0.2.6](https://github.com/mymarilyn/clickhouse-driver), drop support for python3.6.
+
 ### 1.0.2 (2023-02-28)
 - Fix test db name when NAME not provided in DATABASES setting.
 - Fix Enum error when provided an IntegerChoices value.

README.md

@@ -31,7 +31,7 @@ Read [Documentation](https://github.com/jayvynl/django-clickhouse-backend/blob/m
 
 **Requirements:**
 
-- [Python](https://www.python.org/) >= 3.6
+- [Python](https://www.python.org/) >= 3.7
 - [Django](https://docs.djangoproject.com/) >= 3.2
 - [clickhouse driver](https://github.com/mymarilyn/clickhouse-driver)
 - [clickhouse pool](https://github.com/ericmccarthy7/clickhouse-pool)

clickhouse_backend/VERSION

@@ -1 +1 @@
-1.0.2
+1.0.3

clickhouse_backend/driver/__init__.py

@@ -9,9 +9,7 @@
 
 from .connection import Connection
 # Binary is compatible for django's BinaryField.
-from .types import (  # NOQA
-    Binary
-)
+from .types import Binary  # NOQA
 
 
 def connect(dsn=None, host=None,

clickhouse_backend/driver/connection.py

@@ -1,15 +1,70 @@
 import re
+from typing import Dict
 
-from clickhouse_driver.dbapi import connection
+from clickhouse_driver import connection
+from clickhouse_driver.dbapi import connection as dbapi_connection
 from clickhouse_driver.dbapi import cursor
 from clickhouse_driver.dbapi import errors
 from clickhouse_pool.pool import ChPoolError
 
+from .escape import escape_params
 from .pool import ClickhousePool
 
 update_pattern = re.compile(r'\s*alter\s+table\s+(.+)\s+update.+where\s+(.+)', flags=re.IGNORECASE)
 
 
+def send_query(self, query, query_id=None, params=None):
+    if not self.connected:
+        self.connect()
+
+    connection.write_varint(connection.ClientPacketTypes.QUERY, self.fout)
+
+    connection.write_binary_str(query_id or '', self.fout)
+
+    revision = self.server_info.used_revision
+    if revision >= connection.defines.DBMS_MIN_REVISION_WITH_CLIENT_INFO:
+        client_info = connection.ClientInfo(self.client_name, self.context,
+                                            client_revision=self.client_revision)
+        client_info.query_kind = connection.ClientInfo.QueryKind.INITIAL_QUERY
+
+        client_info.write(revision, self.fout)
+
+    settings_as_strings = (
+            revision >= connection.defines
+            .DBMS_MIN_REVISION_WITH_SETTINGS_SERIALIZED_AS_STRINGS
+    )
+    settings_flags = 0
+    if self.settings_is_important:
+        settings_flags |= connection.SettingsFlags.IMPORTANT
+    connection.write_settings(self.context.settings, self.fout,
+                              settings_as_strings, settings_flags)
+
+    if revision >= connection.defines.DBMS_MIN_REVISION_WITH_INTERSERVER_SECRET:
+        connection.write_binary_str('', self.fout)
+
+    connection.write_varint(connection.QueryProcessingStage.COMPLETE, self.fout)
+    connection.write_varint(self.compression, self.fout)
+
+    connection.write_binary_str(query, self.fout)
+
+    if revision >= connection.defines.DBMS_MIN_PROTOCOL_VERSION_WITH_PARAMETERS:
+        if not isinstance(params, Dict):
+            params = None
+        # Always settings_as_strings = True
+        escaped = escape_params(
+            params or {}, self.context, for_server=True
+        )
+        connection.write_settings(escaped, self.fout, True, connection.SettingsFlags.CUSTOM)
+
+    connection.logger.debug('Query: %s', query)
+
+    self.fout.flush()
+
+
+# Monkey patch to resolve https://github.com/jayvynl/django-clickhouse-backend/issues/14
+connection.Connection.send_query = send_query
+
+
 class Cursor(cursor.Cursor):
     def close(self):
         """Push client back to connection pool"""
@@ -46,7 +101,7 @@ def execute(self, operation, parameters=None):
         super().execute(operation, parameters)
 
 
-class Connection(connection.Connection):
+class Connection(dbapi_connection.Connection):
     """Connection class with support for connection pool."""
     def __init__(self, *args, **kwargs):
         super().__init__(*args, **kwargs)

clickhouse_backend/driver/escape.py

@@ -1,4 +1,4 @@
-from datetime import date, datetime, timezone
+from datetime import date, datetime, time, timezone
 from enum import Enum
 from ipaddress import IPv4Address, IPv6Address
 from typing import Sequence, Dict, Union
@@ -37,7 +37,8 @@ def escape_binary(item: bytes, context):
     return b2s[1:]
 
 
-def escape_param(item, context):
+@escape.maybe_enquote_for_server
+def escape_param(item, context, for_server=False):
     if item is None:
         return 'NULL'
 
@@ -47,17 +48,23 @@ def escape_param(item, context):
     elif isinstance(item, date):
         return "'%s'" % item.strftime('%Y-%m-%d')
 
+    elif isinstance(item, time):
+        return "'%s'" % item.strftime('%H:%M:%S')
+
     elif isinstance(item, str):
+        # We need double escaping for server-side parameters.
+        if for_server:
+            item = ''.join(escape.escape_chars_map.get(c, c) for c in item)
         return "'%s'" % ''.join(escape.escape_chars_map.get(c, c) for c in item)
 
     elif isinstance(item, list):
-        return "[%s]" % ', '.join(str(escape_param(x, context)) for x in item)
+        return "[%s]" % ', '.join(str(escape_param(x, context, for_server=for_server)) for x in item)
 
     elif isinstance(item, tuple):
-        return "(%s)" % ', '.join(str(escape_param(x, context)) for x in item)
+        return "(%s)" % ', '.join(str(escape_param(x, context, for_server=for_server)) for x in item)
 
     elif isinstance(item, Enum):
-        return escape_param(item.value, context)
+        return escape_param(item.value, context, for_server=for_server)
 
     elif isinstance(item, (UUID, IPv4Address, IPv6Address)):
         return "'%s'" % str(item)
@@ -69,19 +76,19 @@ def escape_param(item, context):
         return item
 
 
-def escape_params(params: Params, context: Dict) -> Params:
+def escape_params(params: Params, context: Dict, for_server=False) -> Params:
     """Escape param to qualified string representation.
 
     This function is not used in INSERT INTO queries.
     """
     if isinstance(params, Dict):
         escaped = {
-            key: escape_param(value, context)
+            key: escape_param(value, context, for_server=for_server)
             for key, value in params.items()
         }
     else:
         escaped = tuple(
-            escape_param(value, context)
+            escape_param(value, context, for_server=for_server)
             for value in params
         )
 

clickhouse_backend/models/fields/__init__.py

@@ -149,22 +149,6 @@ class DateField(FieldMixin, fields.DateField):
     """Support integer or float may cause strange behavior,
     as integer and float are always treated as UTC timestamps,
     clickhouse store them as date in utc, which may not be what you want.
-
-    Due to a bug of clickhouse-driver 0.2.5,
-    when set null and low_cardinality the same time to DateField or Date32Field,
-    an exception will be raised when create a row.
-    The same bug is also in UUIDField.
-    Below is the minimum reproducing code:
-
-    from clickhouse_driver import Client
-    from datetime import date
-
-    client = Client('localhost', settings={'allow_suspicious_low_cardinality_types': 1})
-    client.execute('create table test (lnd LowCardinality(Nullable(Date))) engine MergeTree order by ()')
-    client.execute('insert into test values', [{'lnd': date.today()}])
-
-    ...
-    AttributeError: 'int' object has no attribute 'year'
     """
     def __init__(self, *args, low_cardinality=False, **kwargs):
         self.low_cardinality = low_cardinality

docs/Fields.md

@@ -165,13 +165,6 @@ DATABASES = {
 }
 ```
 
-**Note:**
-
-Due to a [bug](https://github.com/mymarilyn/clickhouse-driver/issues/363) of clickhouse-driver 0.2.5,
-when set `null=True` and `low_cardinality=True` at the same time to UUIDField, an exception will be raised when inserting a row.
-
-The same bug also exists in DateField and Date32Field.
-
 
 ### Date and Date32
 
@@ -206,14 +199,6 @@ clickhouse store them as date in the [server timezone](https://clickhouse.com/do
 So this feature is not implemented currently.
 
 
-**Note:**
-
-Due to a [bug](https://github.com/mymarilyn/clickhouse-driver/issues/363) of clickhouse-driver 0.2.5,
-when set `null=True` and `low_cardinality=True` at the same time to DateField or Date32Field, an exception will be raised when inserting a row.
-
-The same bug also exists in UUIDField.
-
-
 ### DateTime and DateTime64
 
 Fields importing path: `clickhouse_backend.models.DateTime[64]Field`

setup.py

@@ -21,10 +21,10 @@ def read(name):
     long_description_content_type="text/markdown",
     license="MIT",
     keywords='Django ClickHouse database backend engine driver',
-    python_requires='>=3.6, <4',
+    python_requires='>=3.7, <4',
     install_requires=[
         "django>=3.2",
-        "clickhouse-driver==0.2.5",
+        "clickhouse-driver==0.2.6",
         "clickhouse-pool==0.5.3",
     ],
     classifiers=[
@@ -38,7 +38,6 @@ def read(name):
         "Programming Language :: Python",
         "Programming Language :: Python :: 3",
         "Programming Language :: Python :: 3 :: Only",
-        "Programming Language :: Python :: 3.6",
         "Programming Language :: Python :: 3.7",
         "Programming Language :: Python :: 3.8",
         "Programming Language :: Python :: 3.9",

tox.ini

@@ -1,5 +1,5 @@
 [tox]
-env_list = py{36,37}-django32, py{38,39,310,311}-django{32,40,41}
+env_list = py37-django32, py{38,39,310,311}-django{32,40,41}
 
 [testenv]
 deps =