:add: revision version with the b3j0f.utils.proxy.__getproxy__ attribute

b3j0f/utils/__init__.py

@@ -24,5 +24,8 @@
 # SOFTWARE.
 # --------------------------------------------------------------------
 
+"""b3j0f.utils package.
+"""
+
 #: project version
-__version__ = '0.9.3'
+__version__ = '0.9.4'

b3j0f/utils/proxy.py

@@ -63,6 +63,8 @@
 __PROXY_CLASS__ = 'Proxy'
 #: attribute name for proxified element
 __PROXIFIED__ = '__proxified__'
+#: instance method name for delegating proxy generation to the elt to proxify
+__GETPROXY__ = '__getproxy__'
 
 
 def proxify_elt(elt, bases=None, _dict=None):
@@ -148,11 +150,6 @@ def proxify_routine(routine, impl=None):
     # init impl
     impl = routine if impl is None else impl
 
-    try:
-        __file__ = getfile(routine)
-    except TypeError:
-        __file__ = '<string>'
-
     is_method = ismethod(routine)
     if is_method:
         function = routine.__func__
@@ -184,73 +181,67 @@ def proxify_routine(routine, impl=None):
                 updated.append(wrapper_update)
 
         @wraps(function, assigned=assigned, updated=updated)
-        def function(*args, **kwargs):
-            pass
-
-    # get params from routine wrapper
-    args, varargs, kwargs, _ = getargspec(function)
+        def wrappedfunction(*args, **kwargs):
+            """Default wrap function.
+            """
+        function = wrappedfunction
+        # get params from function
+        args, varargs, kwargs, _ = getargspec(function)
 
-    # get params from routine
     name = function.__name__
 
-    # flag for lambda function
-    islambda = __LAMBDA_NAME__ == function.__name__
-    if islambda:
-        name = '_{0}'.format(int(time()))
-
-    # get join method for reducing concatenation time execution
-    join = "".join
+    result = _compilecode(
+        function=function, name=name, impl=impl,
+        args=args, varargs=varargs, kwargs=kwargs
+    )
 
-    # default indentation
-    indent = '    '
-
-    if islambda:
-        newcodestr = "{0} = lambda ".format(name)
-    else:
-        newcodestr = "def {0}(".format(name)
+    # set wrapping assignments
+    for wrapper_assignment in WRAPPER_ASSIGNMENTS:
+        try:
+            value = getattr(function, wrapper_assignment)
+        except AttributeError:
+            pass
+        else:
+            setattr(result, wrapper_assignment, value)
+    # set proxy module
+    result.__module__ = proxify_routine.__module__
+    # update wrapping updating
+    for wrapper_update in WRAPPER_UPDATES:
+        try:
+            value = getattr(function, wrapper_update)
+        except AttributeError:
+            pass
+        else:
+            getattr(result, wrapper_update).update(value)
 
-    if args:
-        newcodestr = join((newcodestr, "{0}".format(args[0])))
-    for arg in args[1:]:
-        newcodestr = join((newcodestr, ", {0}".format(arg)))
+    # set proxyfied element on proxy
+    setattr(result, __PROXIFIED__, routine)
 
-    if varargs is not None:
-        if args:
-            newcodestr = join((newcodestr, ", "))
-        newcodestr = join((newcodestr, "*{0}".format(varargs)))
+    if is_method:  # create a new method
+        args = [result, routine.__self__]
+        if PY2:
+            args.append(routine.im_class)
+        result = MethodType(*args)
 
-    if kwargs is not None:
-        if args or varargs is not None:
-            newcodestr = join((newcodestr, ", "))
-        newcodestr = join((newcodestr, "**{0}".format(kwargs)))
+    return result
 
-    # insert impl call
-    if islambda:
-        newcodestr = join((newcodestr, ": impl("))
-    else:
-        newcodestr = join(
-            (
-                newcodestr,
-                "):\n{0}return impl(".format(indent)
-            )
-        )
 
-    if args:
-        newcodestr = join((newcodestr, "{0}".format(args[0])))
-    for arg in args[1:]:
-        newcodestr = join((newcodestr, ", {0}".format(arg)))
+def _compilecode(function, name, impl, args, varargs, kwargs):
+    """Get generated code.
 
-    if varargs is not None:
-        if args:
-            newcodestr = join((newcodestr, ", "))
-        newcodestr = join((newcodestr, "*{0}".format(varargs)))
+    :return: function proxy generated code.
+    :rtype: str
+    """
 
-    if kwargs is not None:
-        if args or varargs is not None:
-            newcodestr = join((newcodestr, ", "))
-        newcodestr = join((newcodestr, "**{0}".format(kwargs)))
+    newcodestr, generatedname = _generatecode(
+        function=function, name=name, impl=impl,
+        args=args, varargs=varargs, kwargs=kwargs
+    )
 
-    newcodestr = join((newcodestr, ")\n"))
+    try:
+        __file__ = getfile(function)
+    except TypeError:
+        __file__ = '<string>'
 
     # compile newcodestr
     code = compile(newcodestr, __file__, 'single')
@@ -260,7 +251,7 @@ def function(*args, **kwargs):
     exec(code, _globals)
 
     # get new code
-    newco = _globals[name].__code__
+    newco = _globals[generatedname].__code__
 
     # get new consts list
     newconsts = list(newco.co_consts)
@@ -292,7 +283,7 @@ def function(*args, **kwargs):
         index += 1
 
     # get code string
-    codestr = bytes(newcode) if PY3 else join([chr(co) for co in newcode])
+    codestr = bytes(newcode) if PY3 else "".join([chr(co) for co in newcode])
 
     # get vargs
     vargs = [
@@ -316,51 +307,105 @@ def function(*args, **kwargs):
             codeobj, function.__globals__, function.__name__,
             function.__defaults__, function.__closure__
         )
-    # set wrapping assignments
-    for wrapper_assignment in WRAPPER_ASSIGNMENTS:
-        try:
-            value = getattr(function, wrapper_assignment)
-        except AttributeError:
-            pass
-        else:
-            setattr(result, wrapper_assignment, value)
-    # set proxy module
-    result.__module__ = proxify_routine.__module__
-    # update wrapping updating
-    for wrapper_update in WRAPPER_UPDATES:
-        try:
-            value = getattr(function, wrapper_update)
-        except AttributeError:
-            pass
-        else:
-            getattr(result, wrapper_update).update(value)
 
-    # set proxyfied element on proxy
-    setattr(result, __PROXIFIED__, routine)
+    return result
 
-    if is_method:  # create a new method
-        args = [result, routine.__self__]
-        if PY2:
-            args.append(routine.im_class)
-        result = MethodType(*args)
+
+def _generatecode(function, name, impl, args, varargs, kwargs):
+
+    code = ''
+
+    # flag for lambda function
+    islambda = __LAMBDA_NAME__ == name
+    if islambda:
+        generatedname = '_{0}'.format(int(time()))
+    else:
+        generatedname = name
+
+    # get join method for reducing concatenation time execution
+    join = "".join
+
+    # default indentation
+    indent = '    '
+
+    if islambda:
+        code = "{0} = lambda ".format(generatedname)
+    else:
+        code = "def {0}(".format(generatedname)
+
+    if args:
+        code = join((code, "{0}".format(args[0])))
+    for arg in args[1:]:
+        code = join((code, ", {0}".format(arg)))
+
+    if varargs is not None:
+        if args:
+            code = join((code, ", "))
+        code = join((code, "*{0}".format(varargs)))
+
+    if kwargs is not None:
+        if args or varargs is not None:
+            code = join((code, ", "))
+        code = join((code, "**{0}".format(kwargs)))
+
+    # insert impl call
+    if islambda:
+        code = join((code, ": impl("))
+    else:
+        code = join(
+            (
+                code,
+                "):\n{0}return impl(".format(indent)
+            )
+        )
+
+    if args:
+        code = join((code, "{0}".format(args[0])))
+    for arg in args[1:]:
+        code = join((code, ", {0}".format(arg)))
+
+    if varargs is not None:
+        if args:
+            code = join((code, ", "))
+        code = join((code, "*{0}".format(varargs)))
+
+    if kwargs is not None:
+        if args or varargs is not None:
+            code = join((code, ", "))
+        code = join((code, "**{0}".format(kwargs)))
+
+    code = join((code, ")\n"))
+
+    result = code, generatedname
 
     return result
 
 
 def get_proxy(elt, bases=None, _dict=None):
     """Get proxy from an elt.
 
+    If elt implements the proxy generator method (named ``__getproxy__``), use
+    it instead of using this module functions.
+
     :param elt: elt to proxify.
     :type elt: object or function/method
     :param bases: base types to enrich in the result cls if not None.
     :param _dict: class members to proxify if not None.
     """
 
-    if isroutine(elt):
-        result = proxify_routine(elt)
+    # try to find an instance proxy generator
+    proxygenerator = getattr(elt, __GETPROXY__, None)
+
+    # if a proxy generator is not found, use this module
+    if proxygenerator is None:
+        if isroutine(elt):
+            result = proxify_routine(elt)
+
+        else:  # in case of object, result is a Proxy
+            result = proxify_elt(elt, bases=bases, _dict=_dict)
 
-    else:  # in case of object, result is a Proxy
-        result = proxify_elt(elt, bases=bases, _dict=_dict)
+    else:  # otherwise, use the specific proxy generator
+        result = proxygenerator()
 
     return result
 

b3j0f/utils/test/proxy.py

@@ -203,6 +203,28 @@ def test_elt_bases_dict(self):
 
         self._assert_elt(add_bases=True, add_dict=True)
 
+    def test__getproxy__(self):
+        """Test the __getproxy__ instance method.
+        """
+
+        testproxy = 'test'
+
+        class Test(object):
+            """Test class.
+            """
+            def __getproxy__(self):
+                """Specific get_proxy function to use in order to proxify a
+                Test instance.
+                """
+
+                return testproxy
+
+        test = Test()
+
+        proxy = get_proxy(elt=test)
+
+        self.assertEqual(proxy, testproxy)
+
 
 if __name__ == '__main__':
     main()

changelog.rst

@@ -1,6 +1,11 @@
 ChangeLog
 =========
 
+0.9.4 (27/06/15)
+----------------
+
+- add __getproxy__ instance method name in order to specialize the generation of a proxy from the elt to proxify.
+
 0.9.3 (14/06/15)
 ----------------
 

setup.py

@@ -46,7 +46,7 @@
 
 setup(
     name='b3j0f.utils',
-    version='0.9.3',
+    version='0.9.4',
     packages=find_packages(exclude=['test.*', '*.test.*']),
     author='b3j0f',
     author_email='jlabejof@yahoo.fr',