From 98d82f06a831f28d7ba09680dffb2c29e0072f53 Mon Sep 17 00:00:00 2001
From: Matthew Scragg <scragg@gmail.com>
Date: Wed, 8 Oct 2014 22:42:29 -0500
Subject: [PATCH] hook WIP

---
 .travis.yml                   |  1 -
 VERSION                       |  2 +-
 realms/__init__.py            | 16 ++++++++--
 realms/lib/hook.py            | 57 +++++++++++++++++++++++++++++++++++
 realms/lib/model.py           |  1 -
 realms/modules/wiki/models.py |  3 +-
 6 files changed, 74 insertions(+), 6 deletions(-)
 create mode 100644 realms/lib/hook.py

diff --git a/.travis.yml b/.travis.yml
index 63ef3ba..ef9e077 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -1,6 +1,5 @@
 language: python
 python:
-  - "2.6"
   - "2.7"
 
 before_install:
diff --git a/VERSION b/VERSION
index 9325c3c..a2268e2 100644
--- a/VERSION
+++ b/VERSION
@@ -1 +1 @@
-0.3.0
\ No newline at end of file
+0.3.1
\ No newline at end of file
diff --git a/realms/__init__.py b/realms/__init__.py
index 4c63701..de30b1b 100644
--- a/realms/__init__.py
+++ b/realms/__init__.py
@@ -20,12 +20,13 @@ import click
 from flask import Flask, request, render_template, url_for, redirect, g
 from flask.ext.cache import Cache
 from flask.ext.login import LoginManager, current_user
-from flask.ext.sqlalchemy import SQLAlchemy
+from flask.ext.sqlalchemy import SQLAlchemy, declarative_base, Model, _QueryProperty
 from flask.ext.assets import Environment, Bundle
 from werkzeug.routing import BaseConverter
 from werkzeug.exceptions import HTTPException
 
 from realms.lib.util import to_canonical, remove_ext, mkdir_safe, gravatar_url, to_dict
+from realms.lib.hook import HookModelMeta
 
 
 class Application(Flask):
@@ -55,6 +56,7 @@ class Application(Flask):
             'commands',
             'models',
             'views',
+            'hooks'
         )
 
         start_time = time.time()
@@ -88,6 +90,16 @@ class Application(Flask):
         return super(Application, self).make_response(tuple(rv))
 
 
+class MySQLAlchemy(SQLAlchemy):
+
+    def make_declarative_base(self):
+        """Creates the declarative base."""
+        base = declarative_base(cls=Model, name='Model',
+                                metaclass=HookModelMeta)
+        base.query = _QueryProperty(self)
+        return base
+
+
 class Assets(Environment):
     default_filters = {'js': 'rjsmin', 'css': 'cleancss'}
     default_output = {'js': 'assets/%(version)s.js', 'css': 'assets/%(version)s.css'}
@@ -181,7 +193,7 @@ def cli():
 login_manager = LoginManager(app)
 login_manager.login_view = 'auth.login'
 
-db = SQLAlchemy(app)
+db = MySQLAlchemy(app)
 cache = Cache(app)
 
 assets = Assets(app)
diff --git a/realms/lib/hook.py b/realms/lib/hook.py
new file mode 100644
index 0000000..e4b2795
--- /dev/null
+++ b/realms/lib/hook.py
@@ -0,0 +1,57 @@
+from flask.ext.sqlalchemy import DeclarativeMeta
+
+from functools import wraps
+
+
+def hook_func(name, fn):
+    @wraps(fn)
+    def wrapper(self, *args, **kwargs):
+        for hook, a, kw in self.__class__._pre_hooks.get(name) or []:
+            hook(*a, **kw)
+
+        rv = fn(self, *args, **kwargs)
+
+        for hook, a, kw in self.__class__._post_hooks.get(name) or []:
+            hook(*a, **kw)
+
+        return rv
+    return wrapper
+
+
+class HookMixinMeta(type):
+    def __new__(cls, name, bases, attrs):
+        super_new = super(HookMixinMeta, cls).__new__
+
+        for key, value in attrs.items():
+            if callable(value):
+                attrs[key] = hook_func(key, value)
+
+        return super_new(cls, name, bases, attrs)
+
+
+class HookMixin(object):
+    __metaclass__ = HookMixinMeta
+
+    _pre_hooks = {}
+    _post_hooks = {}
+
+    @classmethod
+    def after(cls, method_name):
+        def outer(f, *args, **kwargs):
+            cls._post_hooks.setdefault(method_name, []).append((f, args, kwargs))
+            return f
+        return outer
+
+
+    @classmethod
+    def before(cls, method_name):
+        def outer(f, *args, **kwargs):
+            cls._pre_hooks.setdefault(method_name, []).append((f, args, kwargs))
+            return f
+        return outer
+
+
+class HookModelMeta(DeclarativeMeta, HookMixinMeta):
+    pass
+
+
diff --git a/realms/lib/model.py b/realms/lib/model.py
index 015ae43..ecdd3a4 100644
--- a/realms/lib/model.py
+++ b/realms/lib/model.py
@@ -44,7 +44,6 @@ class Model(db.Model):
         >>> {u'email': u'john@localhost', u'posts': [{u'id': 1, u'title': u'My First Post'}], u'name': u'John', u'id': 1}
     """
     __abstract__ = True
-
     # Stores changes made to this model's attributes. Can be retrieved
     # with model.changes
     _changes = {}
diff --git a/realms/modules/wiki/models.py b/realms/modules/wiki/models.py
index 9d2c8e4..3545666 100644
--- a/realms/modules/wiki/models.py
+++ b/realms/modules/wiki/models.py
@@ -10,9 +10,10 @@ from dulwich.repo import NotGitRepository
 from werkzeug.utils import escape, unescape
 from realms.lib.util import to_canonical
 from realms import cache
+from realms.lib.hook import HookMixin
 
 
-class Wiki():
+class Wiki(HookMixin):
     path = None
     base_path = '/'
     default_ref = 'master'