Push the version to 0.3.3. Stabilize the hook engine. Now the unhook functionality is safe and stable

XericZephyr · XericZephyr · commit ba36d08e95d9 · 2015-10-06T21:11:13.000-05:00
diff --git a/CHANGES.md b/CHANGES.md
@@ -1,4 +1,8 @@
 # What's new?
+ 
+ * Version 0.3.3
+    - Swirl to a stabilized hook engine adopted by 0.3.0
+    - Unhook is much safer than v0.3.2
 
  * Version 0.3.2
     - Improved hook engine. Now it can do safely unhook.
diff --git a/ProtoText/__init__.py b/ProtoText/__init__.py
@@ -1,8 +1,8 @@
 from .models import MessageWrapper
-from .hook_helper import register_class_hook, ClassHookHelper
+from .hook_helper import register_class_hook, deregister_class_hook
 
 __author__ = 'zhengxu'
-__version__ = '0.3.2'
+__version__ = '0.3.3'
 
 try:
     from google.protobuf.message import Message
@@ -15,19 +15,15 @@
 #   Hook Message class by MessageWrapper
 #
 MESSAGE_WRAPPER_CLASS = [MessageWrapper]
-HOOK_HELPER_CLASS = []
 
 
 def prototext_hook():
-    global HOOK_HELPER_CLASS
-    HOOK_HELPER_CLASS = [ClassHookHelper(x) for x in MESSAGE_WRAPPER_CLASS]
-    for hhc in HOOK_HELPER_CLASS:
-        hhc.hook()
+    for mwc in MESSAGE_WRAPPER_CLASS:
+        register_class_hook(mwc)
 
 
 def prototext_unhook():
-    for hhc in HOOK_HELPER_CLASS:
-        hhc.unhook()
-
+    for mwc in MESSAGE_WRAPPER_CLASS:
+        deregister_class_hook(mwc)
 
 prototext_hook()
diff --git a/ProtoText/hook_helper.py b/ProtoText/hook_helper.py
@@ -1,83 +1,10 @@
 import types
-import inspect
 import __builtin__
 import logging
 
-logger = logging.getLogger(__name__)
-
-"""
-    TODO:
-        - Add ModuleHookHelper and remove the deprecated code
-        - Append the old function pointer to the original message object.
-        - Try to avoid multiple hook at the same time.
-"""
-
-
-class ClassHookHelper(object):
-    def __init__(self, cls, **kwargs):
-        """
-        :param cls:  the class object of the class hook
-        :param strategy:  'safe' or 'override' default: safe
-        :param skip_buildin: determine if we skip the build in object default: True
-        :return:
-        """
-        # TODO: Add more strict check for eligible class
-        assert isinstance(cls, (type, types.ClassType)), \
-            "The input object must be a class object"
-        self._hook_class = cls
-        self._hook_table = {}
-        self._strategy = kwargs.get('strategy', 'safe')
-        self._skip_buildin_class = kwargs.get('skip_buildin_class', True)
-
-    def hook(self, strategy=None, skip_buildin=None):
-        strategy = strategy or self._strategy
-        skip_buildin = skip_buildin or self._skip_buildin_class
-        cls = self._hook_class
-        base_classes = cls.__bases__
-        for base_class in base_classes:
-            if skip_buildin and base_class.__name__ in __builtin__.__dict__:
-                logger.warn("Skip hooking build-in base class '%s' in sub-class '%s' ..." %
-                            (base_class.__name__, cls.__name__))
-                continue
-            for x in cls.__dict__:
-                if not (x in base_class.__dict__ and strategy == 'safe'):
-                    # instance method
-                    if isinstance(cls.__dict__[x], (types.FunctionType, classmethod, staticmethod, property)):
-                        # build hook table
-                        if not (base_class.__name__ in self._hook_table and
-                                    isinstance(self._hook_table[base_class.__name__], dict)):
-                            self._hook_table[base_class.__name__] = {}
-                        self._hook_table[base_class.__name__][x] = \
-                            (base_class.__dict__[x] if base_class.__dict__.has_key(x) else None, cls.__dict__[x])
-                        logger.debug("Wrapping [%s] %s" % (x, str(cls.__dict__[x])))
-                        setattr(base_class, x, cls.__dict__[x])
-                else:
-                    logger.debug("Skip wrapping [%s] %s for security consideration" % (x, str(cls.__dict__[x])))
+HOOK_TABLE_NAME = '__ZX_PY_HOOK_TABLE__'
 
-    def unhook(self):
-        cls = self._hook_class
-        base_classes = cls.__bases__
-        for base_class in base_classes:
-            if base_class.__name__ in self._hook_table:
-                _sub_hook_table = self._hook_table[base_class.__name__]
-                for x in cls.__dict__:
-                    if x in _sub_hook_table:
-                        if _sub_hook_table[x][1] != cls.__dict__[x]:
-                            logger.error("Error! This hook is not installed by this helper. [%s] %s != %s " %
-                                         (x, _sub_hook_table[x][1], str(cls.__dict__[x])))
-                            continue
-                        if _sub_hook_table[x][0] is None:
-                            logger.debug("Delete [%s] %s for unhooking" % (x, str(cls.__dict__[x])))
-                            delattr(base_class, x)
-                        else:
-                            logger.debug("Recover [%s] %s to %s for unhooking" %
-                                         (x, str(cls.__dict__[x]), str(_sub_hook_table[x][0])))
-                            setattr(base_class, x, _sub_hook_table[x][0])
-
-
-"""
-    Deprecated Code, subject to elimination in the near future.
-"""
+logger = logging.getLogger(__name__)
 
 
 def register_class_hook(cls, strategy='safe', skip_buildin=True):
@@ -95,11 +22,23 @@ def register_class_hook(cls, strategy='safe', skip_buildin=True):
             logger.warn("Skip hooking build-in base class '%s' in sub-class '%s' ..." %
                         (base_class.__name__, cls.__name__))
             continue
+        if HOOK_TABLE_NAME in base_class.__dict__:
+            logger.warn("Skip hooking the base class %s to avoid multi-hook conflict ..." %
+                        base_class.__name__)
+            continue
+        else:
+            # build HOOK_TABLE
+            setattr(base_class, HOOK_TABLE_NAME, {})
+            assert HOOK_TABLE_NAME in base_class.__dict__, "Unable to append hook table to target class"
         for x in cls.__dict__:
             if not (x in base_class.__dict__ and strategy == 'safe'):
                 # instance method
                 if isinstance(cls.__dict__[x], (types.FunctionType, classmethod, staticmethod, property)):
                     logger.debug("Wrapping [%s] %s" % (x, str(cls.__dict__[x])))
+                    # Append hook table
+                    base_class.__dict__[HOOK_TABLE_NAME][x] = base_class.__dict__[x] \
+                        if x in base_class.__dict__ else None
+                    # Set hook
                     setattr(base_class, x, cls.__dict__[x])
             else:
                 logger.debug("Skip wrapping [%s] %s for security consideration" % (x, str(cls.__dict__[x])))
@@ -114,43 +53,14 @@ def deregister_class_hook(cls):
         "The input object must be a class object"
     base_classes = cls.__bases__
     for base_class in base_classes:
-        for x in cls.__dict__:
-            if x in base_class.__dict__:
-                # instance method
-                if cls.__dict__[x] == base_class.__dict__[x] and \
-                        isinstance(cls.__dict__[x], (types.FunctionType, classmethod, staticmethod, property)):
-                    logger.debug("Remove warping [%s] %s" % (x, str(cls.__dict__[x])))
-                    delattr(base_class, x)
-
-
-def register_module_hook(class_name_list=[], allow_recursive=False, **kwargs):
-    """
-    Enumerate all classes in the caller module, hook all or selected classes' base
-    classes with specific module
-    :param class_name_list: given the class list you'd like to hook
-    :return:
-    """
-    try:
-        #
-        #   Fetch the caller module
-        #
-        parent_frame = inspect.stack()[1][0]
-        caller_module = inspect.getmodule(parent_frame)
-        class_list = [v for k, v in caller_module.__dict__.iteritems()
-                      if ((k in class_name_list) or not class_name_list) and
-                      isinstance(v, (type, types.ClassType))]
-        base_classes_list = reduce(lambda x, y: x + list(y.__bases__), class_list, [])
-        if not allow_recursive:
-            class_list = filter(lambda x: x not in base_classes_list, class_list)
-    except Exception, e:
-        logger.error("Unable to retrieve the caller module : %s" % str(e))
-        return
-    for c in class_list:
-        try:
-            #
-            #   Do the class hook
-            #
-            register_class_hook(c, **kwargs)
-        except Exception, e:
-            logger.error("Unable to register class hook")
+        if HOOK_TABLE_NAME not in base_class.__dict__:
+            logger.warn("Unable to find Hook Table for class '%s', "
+                        "probably it's not properly hooked." % base_class.__name__)
             continue
+        _hook_table = base_class.__dict__[HOOK_TABLE_NAME]
+        for x in _hook_table:
+            if _hook_table[x]:
+                setattr(base_class, x, _hook_table[x])
+            else:
+                delattr(base_class, x)
+        delattr(base_class, HOOK_TABLE_NAME)
diff --git a/README.md b/README.md
@@ -12,11 +12,11 @@ first.**
 
 ### Installation 
 
-The newest release version is `0.3.0` even though we have some unstable development version ahead of that. 
+The newest release version is `0.3.3` albeit we have some unstable development version ahead of that. 
 To install the package, simply use the `pip` manager:
 
 ```bash
-pip install https://github.com/XericZephyr/prototext/archive/v0.3.0.tar.gz
+pip install https://github.com/XericZephyr/prototext/archive/v0.3.3.tar.gz
 ```
 
 We will publish this module to PyPI as soon as we consider this module as stable. 
@@ -38,11 +38,11 @@ You don't need to anything after that. The hack will be completed automatically
 If you want to do safely removing the prototext hook (pls don't, pls), use 
 
 ```python
-ProtoText.unhook()
+ProtoText.prototext_unhook()
 ```
 
 ~~The unhook part is still very buggy. We are sorry for that.~~ 
-(You didn't see anything in the line above.)
+(We've fixed these bugs. It's safe now. :love_letter: )
 
 #### Dict-Like Operations
  
