Created separate from infi MigrationHistory in order to:

1) inherit it from this library models
2) Use some extra functionality

src/django_clickhouse/configuration.py

@@ -20,6 +20,7 @@ DEFAULTS = {
     'DATABASE_ROUTER': 'django_clickhouse.routers.DefaultRouter',
     'STATSD_PREFIX': 'clickhouse',
     'MIGRATIONS_PACKAGE': 'clickhouse_migrations',
+    'MIGRATION_HISTORY_MODEL': 'django_clickhouse.migrations.MigrationHistory',
     'MIGRATE_WITH_DEFAULT_DB': True,
     'CELERY_QUEUE': 'celery',
     'DEFAULT_DB_ALIAS': 'default'

src/django_clickhouse/database.py

@@ -24,19 +24,7 @@ class Database(InfiDatabase):
                                   ' Use django_clickhouse.migrations module instead.')
 
     def _get_applied_migrations(self, migrations_package_name):
-        # I don't want to create any tables here, so I changed method to work in without table
-        if not self.db_exists:
-            return []
-
-        query = "SELECT module_name from $table WHERE package_name = '%s'" % migrations_package_name
-        query = self._substitute(query, MigrationHistory)
-        try:
-            return set(obj.module_name for obj in self.select(query))
-        except ServerError as ex:
-            # Database doesn't exist or table doesn't exist
-            if ex.code in {81, 60}:
-                return set()
-            raise ex
+        raise NotImplementedError("This method is not supported by django_clickhouse.")
 
 
 class ConnectionProxy:

src/django_clickhouse/migrations.py

@@ -2,11 +2,14 @@
 Migrating database
 """
 import datetime
-from typing import Optional
+from typing import Optional, Set
 
 from django.db import DEFAULT_DB_ALIAS as DJANGO_DEFAULT_DB_ALIAS
 from django.db.models.signals import post_migrate
 from django.dispatch import receiver
+from infi.clickhouse_orm.database import ServerError
+
+from django_clickhouse.clickhouse_models import ClickHouseModel
 from infi.clickhouse_orm.migrations import *
 from infi.clickhouse_orm.utils import import_submodules
 
@@ -29,13 +32,13 @@ class Migration:
         :return: None
         """
         db_router = lazy_class_import(config.DATABASE_ROUTER)()
+        database = database or connections[db_alias]
 
         for op in self.operations:
             model_class = getattr(op, 'model_class', None)
             hints = getattr(op, 'hints', {})
 
             if db_router.allow_migrate(db_alias, self.__module__, op, model=model_class, **hints):
-                database = database or connections[db_alias]
                 op.apply(database)
 
 
@@ -62,20 +65,17 @@ def migrate_app(app_label, db_alias, up_to=9999, database=None):
     if module_exists(migrations_package):
         database = database or connections[db_alias]
 
-        applied_migrations = database._get_applied_migrations(migrations_package)
+        applied_migrations = MigrationHistory.get_applied_migrations(db_alias, migrations_package)
         modules = import_submodules(migrations_package)
-        unapplied_migrations = set(modules.keys()) - set(applied_migrations)
+        unapplied_migrations = set(modules.keys()) - applied_migrations
 
         for name in sorted(unapplied_migrations):
             print('Applying ClickHouse migration %s for app %s in database %s' % (name, app_label, db_alias))
             migration = modules[name].Migration()
             migration.apply(db_alias, database=database)
 
-            # Ensure that table for migration storing is created
-            database.create_table(MigrationHistory)
-            database.insert([
-                MigrationHistory(package_name=migrations_package, module_name=name, applied=datetime.date.today())
-            ])
+            migration_history_model = lazy_class_import(config.MIGRATION_HISTORY_MODEL)
+            migration_history_model.set_migration_applied(db_alias, migrations_package, name)
 
             if int(name[:4]) >= up_to:
                 break
@@ -95,3 +95,56 @@ def clickhouse_migrate(sender, **kwargs):
 
     for db_alias in config.DATABASES:
         migrate_app(app_name, db_alias)
+
+
+class MigrationHistory(ClickHouseModel):
+    """
+    A model for storing which migrations were already applied to database.
+    This
+    """
+
+    db_alias = StringField()
+    package_name = StringField()
+    module_name = StringField()
+    applied = DateField()
+
+    engine = MergeTree('applied', ('db_alias', 'package_name', 'module_name'))
+
+    @classmethod
+    def set_migration_applied(cls, db_alias, migrations_package, name):  # type: (str, str, str) -> None
+        """
+        Sets migration apply status
+        :param db_alias: Database alias migration is applied to
+        :param migrations_package: Package migration is stored in
+        :param name: Migration name
+        :return: None
+        """
+        db = cls.get_database(for_write=True)
+
+        # Ensure that table for migration storing is created
+        db.create_table(MigrationHistory)
+        db.insert([
+            MigrationHistory(db_alias=db_alias, package_name=migrations_package, module_name=name,
+                             applied=datetime.date.today())
+        ])
+
+    @classmethod
+    def get_applied_migrations(cls, db_alias, migrations_package):  # type: (str, str) -> Set[str]
+        """
+        Returns applied migrations names
+        :param db_alias: Database alias, to check
+        :param migrations_package: Package name to check
+        :return: Set of migration names
+        """
+        qs = MigrationHistory.objects.filter(package_name=migrations_package, db_alias=db_alias).only('module_name')
+        try:
+            return set(obj.module_name for obj in qs)
+        except ServerError as ex:
+            # Database doesn't exist or table doesn't exist
+            if ex.code in {81, 60}:
+                return set()
+            raise ex
+
+    @classmethod
+    def table_name(cls):
+        return 'django_clickhouse_migrations'

tests/test_migrations.py

@@ -1,5 +1,5 @@
 from django.test import TestCase, override_settings
-from infi.clickhouse_orm.migrations import MigrationHistory
+from django_clickhouse.migrations import MigrationHistory
 
 from django_clickhouse.database import connections
 from django_clickhouse.migrations import migrate_app