Add context manager "postgres_manager" to enable using manager anywhere

Author: Photonios

psqlextra/util.py

@@ -0,0 +1,21 @@
+import copy
+
+from contextlib import contextmanager
+
+from .manager import PostgresManager
+
+
+@contextmanager
+def postgres_manager(model):
+    """Allows you to use the :see:PostgresManager with
+    the specified model instance on the fly.
+
+    Arguments:
+        model:
+            The model or model instance to use this on.
+    """
+
+    manager = PostgresManager()
+    manager.model = model
+
+    yield manager

tests/fake_model.py

@@ -7,7 +7,7 @@
 from psqlextra.models import PostgresModel
 
 
-def define_fake_model(fields=None):
+def define_fake_model(fields=None, model_base=PostgresModel):
     name = str(uuid.uuid4()).replace('-', '')[:8]
 
     attributes = {
@@ -18,15 +18,15 @@ def define_fake_model(fields=None):
 
     if fields:
         attributes.update(fields)
-    model = type(name, (PostgresModel,), attributes)
+    model = type(name, (model_base,), attributes)
 
     return model
 
 
-def get_fake_model(fields=None):
+def get_fake_model(fields=None, model_base=PostgresModel):
     """Creates a fake model to use during unit tests."""
 
-    model = define_fake_model(fields)
+    model = define_fake_model(fields, model_base)
 
     class TestProject:
 

tests/test_manager_context.py

@@ -0,0 +1,31 @@
+from django.db import models
+from django.test import TestCase
+
+from psqlextra.util import postgres_manager
+
+from .fake_model import get_fake_model
+
+
+class ManagerContextTestCase(TestCase):
+    """Tests whether the :see:postgres_manager context
+    manager works properly."""
+
+    def test_manager_context(self):
+        """Tests whether the :see:postgres_manager context
+        manager can be used to get access to :see:PostgresManager
+        on a model that does not use it directly or inherits
+        from :see:PostgresModel."""
+
+        model = get_fake_model({
+            'myfield': models.CharField(max_length=255, unique=True)
+        }, models.Model)
+
+        with postgres_manager(model) as manager:
+            manager.upsert(
+                conflict_target=['myfield'],
+                fields=dict(
+                    myfield='beer'
+                )
+            )
+
+            assert manager.first().myfield == 'beer'