stateobject: support lists

mitmproxy/stateobject.py

@@ -1,10 +1,18 @@
 from __future__ import absolute_import
 
 import six
+from typing import List, Any
 
 from netlib.utils import Serializable
 
 
+def _is_list(cls):
+    # The typing module backport is somewhat broken.
+    # Python 3.5 or 3.6 should fix this.
+    is_list_bugfix = getattr(cls, "__origin__", False) == getattr(List[Any], "__origin__", True)
+    return issubclass(cls, List) or is_list_bugfix
+
+
 class StateObject(Serializable):
 
     """
@@ -28,8 +36,12 @@ class StateObject(Serializable):
         state = {}
         for attr, cls in six.iteritems(self._stateobject_attributes):
             val = getattr(self, attr)
-            if hasattr(val, "get_state"):
+            if val is None:
+                state[attr] = None
+            elif hasattr(val, "get_state"):
                 state[attr] = val.get_state()
+            elif _is_list(cls):
+                state[attr] = [x.get_state() for x in val]
             else:
                 state[attr] = val
         return state
@@ -49,6 +61,9 @@ class StateObject(Serializable):
                 elif hasattr(cls, "from_state"):
                     obj = cls.from_state(state.pop(attr))
                     setattr(self, attr, obj)
+                elif _is_list(cls):
+                    cls = cls.__parameters__[0]
+                    setattr(self, attr, [cls.from_state(x) for x in state.pop(attr)])
                 else:  # primitive types such as int, str, ...
                     setattr(self, attr, cls(state.pop(attr)))
         if state:

setup.py

@@ -81,6 +81,7 @@ setup(
         "requests>=2.9.1, <2.10",
         "six>=1.10, <1.11",
         "tornado>=4.3, <4.4",
+        "typing==3.5.1.0",
         "urwid>=1.3.1, <1.4",
         "watchdog>=0.8.3, <0.9",
     ],

test/mitmproxy/test_stateobject.py

@@ -0,0 +1,63 @@
+from typing import List
+
+from mitmproxy.stateobject import StateObject
+
+
+class Child(StateObject):
+    def __init__(self, x):
+        self.x = x
+
+    _stateobject_attributes = dict(
+        x=int
+    )
+
+    @classmethod
+    def from_state(cls, state):
+        obj = cls(None)
+        obj.set_state(state)
+        return obj
+
+
+class Container(StateObject):
+    def __init__(self):
+        self.child = None
+        self.children = None
+
+    _stateobject_attributes = dict(
+        child=Child,
+        children=List[Child],
+    )
+
+    @classmethod
+    def from_state(cls, state):
+        obj = cls()
+        obj.set_state(state)
+        return obj
+
+
+def test_simple():
+    a = Child(42)
+    b = a.copy()
+    assert b.get_state() == {"x": 42}
+    a.set_state({"x": 44})
+    assert a.x == 44
+    assert b.x == 42
+
+
+def test_container():
+    a = Container()
+    a.child = Child(42)
+    b = a.copy()
+    assert a.child.x == b.child.x
+    b.child.x = 44
+    assert a.child.x != b.child.x
+
+
+def test_container_list():
+    a = Container()
+    a.children = [Child(42), Child(44)]
+    assert a.get_state() == {
+        "child": None,
+        "children": [{"x": 42}, {"x": 44}]
+    }
+    assert len(a.copy().children) == 2