#7 Adds support for filtering objects

pydictdisplayfilter/__init__.py

@@ -14,4 +14,5 @@
 #
 # You should have received a copy of the GNU General Public License
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
-from pydictdisplayfilter.display_filters import DictDisplayFilter, ListDisplayFilter
+from pydictdisplayfilter.display_filters import \
+    DictDisplayFilter, ListDisplayFilter, ObjectDisplayFilter, SQLDisplayFilter

pydictdisplayfilter/display_filters.py

@@ -122,7 +122,7 @@ def filter(self, display_filter: str):
 
 
 class DictDisplayFilter(BaseDisplayFilter):
-    """ Allows to filter a dictionary using a display filter. """
+    """ Allows to filter a list of dictionaries using a display filter. """
 
     def __init__(self,
                  data: List[dict],
@@ -138,7 +138,7 @@ def __init__(self,
         self._data = data
 
     def filter(self, display_filter: str):
-        """ Filters the data using the display filter. """
+        """ Filters the dictionaries using the display filter. """
         expressions = self._display_filter_parser.parse(display_filter)
         yield from self._filter_data(self._data, expressions)
 
@@ -246,3 +246,33 @@ def filter(self, display_filter: str):
         expressions = self._display_filter_parser.parse(display_filter)
         table_data = self._get_table_data()
         yield from self._filter_data(table_data, expressions)
+
+
+class ObjectDisplayFilter(BaseDisplayFilter):
+    """ Allows to filter a list of objects using a display filter. """
+
+    def __init__(self,
+                 data: List[object],
+                 field_names: List[str] = None,
+                 functions: Dict[str, Callable] = None,
+                 slicers: List[BasicSlicer] = None,
+                 evaluator: Evaluator = None):
+        """
+        Initializes the DictDisplayFilter.
+        :param data: A list of dictionaries to filter on.
+        """
+        super().__init__(field_names=field_names, functions=functions, slicers=slicers, evaluator=evaluator)
+        self._data = data
+
+    def _filter_data(self, data: List[object], expressions: List[Union[Expression, str]]) -> List:
+        if expressions:
+            for item in data:
+                if self._evaluate_expressions(expressions, item.__dict__):
+                    yield item
+        else:
+            yield from data
+
+    def filter(self, display_filter: str):
+        """ Filters the objects using the display filter. """
+        expressions = self._display_filter_parser.parse(display_filter)
+        yield from self._filter_data(self._data, expressions)

setup.py

@@ -11,7 +11,7 @@
 # This call to setup() does all the work
 setup(
     name="python-dict-display-filter",
-    version="1.1.0",
+    version="1.2.0",
     description="A Wireshark-like display filter for dictionaries.",
     long_description=README,
     long_description_content_type="text/markdown",

tests/test_object_display_filter.py

@@ -0,0 +1,93 @@
+# vim: ts=8:sts=8:sw=8:noexpandtab
+#
+# This file is part of python-dict-display-filter.
+#
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 2 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+import dataclasses
+import unittest
+from typing import List
+
+from parameterized import parameterized
+
+from pydictdisplayfilter.display_filters import ObjectDisplayFilter
+
+
+class Person:
+
+    def __init__(self, name: str = '', age: int = 0, gender: str = '', killed: bool = False, power: List = None):
+        self.name = name
+        self.age = age
+        self.gender = gender
+        self.killed = killed
+        self.power = power
+
+
+class TestObjectDisplayFilter(unittest.TestCase):
+    # List of objects representing the data to filter on.
+    data = [
+        Person(name="Morpheus", age=38, gender="male", killed=False),
+        Person(name="Neo", age=35, gender="male", killed=False, power=["flight", "bullet-time"]),
+        Person(name="Cipher", age=48, gender="male", killed=True),
+        Person(name="Trinity", age=32, gender="female", killed=False),
+    ]
+
+    @parameterized.expand([
+        # Field existence
+        ['name', 4],
+        ['power', 1],
+        ['not power', 3],
+        # Comparison operators
+        ['name == Neo', 1],
+        ['name == \x4e\x65\x6f', 1],
+        ['killed == True', 1],
+        ['gender == male', 3],
+        ['age == 32', 1],
+        ['age >= 32', 4],
+        ['age > 32', 3],
+        ['age <= 32', 1],
+        ['age <= 040', 1],  # octal value
+        ['age <= 0x20', 1],  # hexadecimal value
+        ['age < 32', 0],
+        ['age ~= 3', 3],  # contains operator
+        ['age ~ 3', 3],  # matches operator
+        ['age & 0x20', 4],  # bitwise and operator
+        # In operator
+        ['age in { 32, 35, 38 }', 3],
+        ['age in { 30..40 }', 3],
+        ['age in { 30-40 }', 3],
+        ['age in { 30.0..40.0 }', 3],
+        ['name in { "Neo", "Trinity" }', 2],
+        # logical operators
+        ['age >= 32 and gender == male', 3],
+        ['name == Neo or name == Trinity', 2],
+        ['gender == female xor power', 2],
+        ['gender == male and (age > 30 and age < 40)', 2],
+        ['gender == male and not (age > 35)', 1],
+        ['gender == male and !(age > 35)', 1],
+        # Functions
+        ('len(name) == 3', 1),
+        ('upper(name) == NEO', 1),
+        ('lower(name) == neo', 1),
+        # Slice Operator
+        ('gender[0] == m', 3),
+        ('gender[-1] == e', 4),
+        ('gender[0:2] == ma', 3),
+        ('gender[:2] == ma', 3),
+        ('gender[2:] == le', 3),
+        ('gender[1-2] == ma', 3),
+        ('gender[0,1] == ma', 3),
+        ('gender[:2,3-4] == male', 3)
+    ])
+    def test_object_display_filter_returns_correct_number_of_items(self, display_filter, no_items):
+        self.assertEqual(len(list(ObjectDisplayFilter(self.data).filter(display_filter))), no_items)