work in progress: rules and action handling

git-svn-id: svn://svn.cy55.de/Zope3/src/cybertools/trunk@2144 fd906abe-77d9-0310-91a1-e0d9ade77398

composer/rule/README.txt

@@ -8,6 +8,10 @@ Rule-based Execution of Actions
   >>> from cybertools.composer.rule.base import RuleManager, Rule, Action
   >>> from cybertools.composer.rule.base import EventType, Event
 
+  >>> from cybertools.composer.rule.base import ActionHandler
+  >>> component.provideAdapter(ActionHandler, name='message')
+  >>> component.provideAdapter(ActionHandler, name='sendmail')
+
   >>> manager = RuleManager()
 
   >>> loginEvent = EventType('login')
@@ -18,7 +22,7 @@ Rule-based Execution of Actions
   >>> checkoutRule.actions.append(Action('message',
   ...                   parameters = dict(messageName='confirmation_mail')))
   >>> checkoutRule.actions.append(Action('sendmail'))
-  >>> manager.rules.append(checkoutRule)
+  >>> manager.addRule(checkoutRule)
 
   >>> manager.handleEvent(Event(loginEvent))
 

composer/rule/base.py

@@ -22,6 +22,8 @@ Basic classes for rules and actions.
 $Id$
 """
 
+from zope import component
+from zope.component import adapts
 from zope.interface import implements
 
 from cybertools.composer.base import Component, Element, Compound
@@ -42,12 +44,29 @@ class RuleManager(object):
     rulesFactory = Jeep
     rules = None
 
-    def __init__(self):
+    def addRule(self, rule):
-        if self.rulesFactory is not None:
+        rule.manager = self
+        if self.rules is None:
             self.rules = self.rulesFactory()
+        for e in rule.events:
+            entry = self.rules.setdefault(e.name, [])
+            entry.append(rule)
+
+    def getRulesForEvent(self, event):
+        return self.rules.get(event.name, [])
 
     def handleEvent(self, event):
-        pass
+        rules = self.getRulesForEvent(event)
+        for r in rules:
+            for c in r.conditions:
+                cond = component.getAdapter(r, ICondition, name=c)
+                if not cond(event):
+                    continue
+            data = None
+            for action in r.actions:
+                handler = component.getAdapter(action, IActionHandler,
+                                               name=action.handlerName)
+                data = handler(data, event)
 
 
 class Rule(Template):
@@ -101,21 +120,13 @@ class Event(object):
 
 # conditions
 
-class ConditionType(object):
-
-    def __init__(self, name, title):
-        self.name = name
-        self.title = title
-
-
 class Condition(object):
 
     implements(ICondition)
+    adapts(IRule)
 
-    def __init__(self, conditionType):
+    def __init__(self, context):
-        self.conditionType = conditionType
+        self.context = context
-        self.name = conditionType.name
-        self.title = conditionType.title
 
     def __call__(self, context, params):
         return True
@@ -123,7 +134,7 @@ class Condition(object):
 
 # actions
 
-class Action(object):
+class Action(Component):
 
     implements(IAction)
 
@@ -133,17 +144,22 @@ class Action(object):
     rule = None
 
     def __init__(self, name, **kw):
+        self.name = name
         for k, v in kw.items():
             setattr(self, k, v)
         if self.parameters is None:
             self.parameters = {}
         if not self.handlerName:
-            self.handlerName = self.name
+            self.handlerName = name
 
 
 class ActionHandler(object):
 
     implements(IActionHandler)
+    adapts(IAction)
 
-    def __call__(self, data, params):
+    def __init__(self, context):
+        self.context = context
+
+    def __call__(self, data, event, params={}):
         pass

composer/rule/interfaces.py

@@ -40,11 +40,21 @@ class IRuleManager(Interface):
                 description=_(u'The title of the object.'),
                 required=True,)
 
-    rules = Attribute('An ordered collection of rules managed by this object.')
+    #rules = Attribute('An ordered collection of rules managed by this object.')
+
+    def addRule(rule):
+        """ Add the rule given to the rule manager's collection of rules,
+            registering it for the event types that are handled by
+            the rule.
+        """
+
+    def getRulesForEvent(event):
+        """ Retrieve the rules that may handle the event given.
+        """
 
     def handleEvent(event):
         """ Handle the event given and apply the corresponding rules
-            to the client object.
+            to the event's context object.
         """
 
 
@@ -66,7 +76,8 @@ class IRule(ITemplate):
                 required=False,)
 
     manager = Attribute('The associated rule manager.')
-    events = Attribute('The events to be handled by this rule.')
+    events = Attribute('The events (the event types, to be more precise) '
+                    'to be handled by this rule.')
     conditions = Attribute('Conditions to be checked.'
                     'This is typically a list of names of ICondition adapters.')
     actions = Attribute('Sequence of actions to be carried out by this rule.')
@@ -81,7 +92,7 @@ class IEvent(Interface):
 
 class ICondition(Interface):
 
-    def __call__(context, params):
+    def __call__(context, event, params):
         """ Should return True if the condition should be fulfilled;
             will allow the rule to call its actions.
         """

organize/service.py

@@ -45,18 +45,16 @@ from cybertools.organize.interfaces import IRegistration, IRegistrationTemplate
 from cybertools.organize.interfaces import IClientRegistrations
 
 
-class ServiceManager(RuleManager):
+class ServiceManager(object):
 
     implements(IServiceManager, IClientManager)
 
     servicesFactory = Jeep
     clientSchemasFactory = Jeep
     clientsFactory = OOBTree
-    rulesFactory = Jeep
 
     services = None
     clients = None
-    rules = None
 
     allowRegWithNumber = False
     allowDirectRegistration = True
@@ -66,8 +64,6 @@ class ServiceManager(RuleManager):
             self.services = self.servicesFactory()
         if self.clientSchemasFactory is not None:
             self.clientSchemas = self.clientSchemasFactory()
-        if self.rulesFactory is not None:
-            self.rules = self.rulesFactory()
 
     def getServices(self, categories=[]):
         return self.services
@@ -94,9 +90,6 @@ class ServiceManager(RuleManager):
     def checkClientName(self, name):
         return name not in self.getClients()
 
-    def getRules(self):
-        return self.rules
-
 
 class Registration(object):
 
@@ -351,13 +344,21 @@ class StatefulRegistration(StatefulAdapter):
     statesDefinition = registrationStates
 
 
-# event types for rule-based processing
+# rules and events
 
 eventTypes = Jeep((
     EventType('service.checkout'),
 ))
 
 
+class RuleManagerAdapter(RuleManager):
+
+    adapts(IServiceManager)
+
+    def __init__(self, context):
+        self.context = context
+
+
 # Zope event handlers
 
 def clientRemoved(obj, event):