Merge pull request #3 from Themis3000/context

Support for context managers

HISTORY.rst

@@ -20,7 +20,12 @@ History
 * Readme updated
 * Docstrings added
 
-1.0.1 (2022-1-2)
-----------------
+1.0.1 (2022-01-02)
+------------------
 
 * Updated python require version to >=3.8 due to usage of the walrus operator
+
+1.1.0 (2022-01-09)
+------------------
+
+* Added support for context managers, the with statement can now be used to open and cleanly exit databases

README.md

@@ -15,10 +15,16 @@ Example usage:
 ```python
 from lazy_db import LazyDb
 
+# Simple example usage
 db = LazyDb("test.lazy")
 db.write("test_value", "value")
 print(db.read("test_value"))  # prints "value"
 db.close()
+
+# Or use a with statement to insure the database file is closed cleanly and avoid having to call db.close() on your own
+with LazyDb("test2.lazy") as db:
+    db.write("test_value", "value")
+    print(db.read("test_value"))
 ```
 
 ## How it works

lazy_db/__init__.py

@@ -3,4 +3,4 @@
 
 __author__ = """Themi Megas"""
 __email__ = '[email protected]'
-__version__ = '1.0.1'
+__version__ = '1.1.0'

lazy_db/lazy_db.py

@@ -303,3 +303,9 @@ def delete(self, key: Union[str, int]):
     def close(self):
         """Closes the database"""
         self.f.close()
+
+    def __enter__(self):
+        return self
+
+    def __exit__(self, exc_type, exc_val, exc_tb):
+        self.close()

setup.cfg

@@ -1,5 +1,5 @@
 [bumpversion]
-current_version = 1.0.1
+current_version = 1.1.0
 commit = True
 tag = False
 

setup.py

@@ -37,6 +37,6 @@
     test_suite='tests',
     tests_require=test_requirements,
     url='https://github.com/Themis3000/lazy_db',
-    version='1.0.1',
+    version='1.1.0',
     zip_safe=False,
 )

tests/test_lazy_db.py

@@ -8,7 +8,7 @@
 from lazy_db import lazy_db
 
 
-class TestLazy_db(unittest.TestCase):
+class TestLazyDb(unittest.TestCase):
     """Tests for `lazy_db` package."""
 
     def setUp(self):
@@ -147,9 +147,35 @@ def test_write_int_list_restart(self):
         self.assertEqual([435, 4636, 123, 768, 2356, 436], self.db.read("test_str"))
         self.assertEqual([436, 2356, 35, 235, 6546, 4537], self.db.read("test_str2"))
 
-    def delete_last_value(self):
+    def test_delete_last_value(self):
         """Deletes the last value in a database and restarts"""
         self.db.write("test_str", "test")
         self.db.delete("test_str")
         self.restart()
         self.assertEqual(0, len(self.db.headers))
+
+
+class TestLazyDbSetupless(unittest.TestCase):
+    """Tests for `lazy_db` package that don't use to use setup or teardown methods."""
+
+    def test_context(self):
+        """Tests if the database can be opened and closed via the with statement."""
+        with lazy_db.LazyDb("test_db.lazydb") as db:
+            db.write("test_str", "test val")
+            self.assertEqual("test val", db.read("test_str"))
+            self.assertFalse(db.f.closed, "file prematurely closed")
+        self.assertTrue(db.f.closed, "file not closed after exiting context")
+        os.remove("test_db.lazydb")
+
+    def test_context_exception(self):
+        """Tests if the database can be opened and closed via the with statement cleanly with an exception"""
+        try:
+            with lazy_db.LazyDb("test_db.lazydb") as db:
+                db.write("test_str", "test val")
+                db.write("test_str", "test val")
+                self.fail("No exception was triggered after inserting 2 keys of the same name into the database")
+        except:
+            pass
+
+        self.assertTrue(db.f.closed)
+        os.remove("test_db.lazydb")