--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/website/issues/detectors/nosyreaction.py	Fri Feb 06 13:16:31 2009 +0000
@@ -0,0 +1,122 @@
+import sets
+
+from roundup import roundupdb, hyperdb
+
+def nosyreaction(db, cl, nodeid, oldvalues):
+    ''' A standard detector is provided that watches for additions to the
+        "messages" property.
+        
+        When a new message is added, the detector sends it to all the users on
+        the "nosy" list for the issue that are not already on the "recipients"
+        list of the message.
+        
+        Those users are then appended to the "recipients" property on the
+        message, so multiple copies of a message are never sent to the same
+        user.
+        
+        The journal recorded by the hyperdatabase on the "recipients" property
+        then provides a log of when the message was sent to whom. 
+    '''
+    # send a copy of all new messages to the nosy list
+    for msgid in determineNewMessages(cl, nodeid, oldvalues):
+        try:
+            cl.nosymessage(nodeid, msgid, oldvalues)
+        except roundupdb.MessageSendError, message:
+            raise roundupdb.DetectorError, message
+
+def determineNewMessages(cl, nodeid, oldvalues):
+    ''' Figure a list of the messages that are being added to the given
+        node in this transaction.
+    '''
+    messages = []
+    if oldvalues is None:
+        # the action was a create, so use all the messages in the create
+        messages = cl.get(nodeid, 'messages')
+    elif oldvalues.has_key('messages'):
+        # the action was a set (so adding new messages to an existing issue)
+        m = {}
+        for msgid in oldvalues['messages']:
+            m[msgid] = 1
+        messages = []
+        # figure which of the messages now on the issue weren't there before
+        for msgid in cl.get(nodeid, 'messages'):
+            if not m.has_key(msgid):
+                messages.append(msgid)
+    return messages
+
+def updatenosy(db, cl, nodeid, newvalues):
+    '''Update the nosy list for changes to the assignedto
+    '''
+    # nodeid will be None if this is a new node
+    current_nosy = sets.Set()
+    if nodeid is None:
+        ok = ('new', 'yes')
+    else:
+        ok = ('yes',)
+        # old node, get the current values from the node if they haven't
+        # changed
+        if not newvalues.has_key('nosy'):
+            nosy = cl.get(nodeid, 'nosy')
+            for value in nosy:
+                current_nosy.add(value)
+
+    # if the nosy list changed in this transaction, init from the new value
+    if newvalues.has_key('nosy'):
+        nosy = newvalues.get('nosy', [])
+        for value in nosy:
+            if not db.hasnode('user', value):
+                continue
+            current_nosy.add(value)
+
+    new_nosy = sets.Set(current_nosy)
+
+    # add assignedto(s) to the nosy list
+    if newvalues.has_key('assignedto') and newvalues['assignedto'] is not None:
+        propdef = cl.getprops()
+        if isinstance(propdef['assignedto'], hyperdb.Link):
+            assignedto_ids = [newvalues['assignedto']]
+        elif isinstance(propdef['assignedto'], hyperdb.Multilink):
+            assignedto_ids = newvalues['assignedto']
+        for assignedto_id in assignedto_ids:
+            new_nosy.add(assignedto_id)
+
+    # see if there's any new messages - if so, possibly add the author and
+    # recipient to the nosy
+    if newvalues.has_key('messages'):
+        if nodeid is None:
+            ok = ('new', 'yes')
+            messages = newvalues['messages']
+        else:
+            ok = ('yes',)
+            # figure which of the messages now on the issue weren't
+            oldmessages = cl.get(nodeid, 'messages')
+            messages = []
+            for msgid in newvalues['messages']:
+                if msgid not in oldmessages:
+                    messages.append(msgid)
+
+        # configs for nosy modifications
+        add_author = getattr(db.config, 'ADD_AUTHOR_TO_NOSY', 'new')
+        add_recips = getattr(db.config, 'ADD_RECIPIENTS_TO_NOSY', 'new')
+
+        # now for each new message:
+        msg = db.msg
+        for msgid in messages:
+            if add_author in ok:
+                authid = msg.get(msgid, 'author')
+                new_nosy.add(authid)
+
+            # add on the recipients of the message
+            if add_recips in ok:
+                for recipient in msg.get(msgid, 'recipients'):
+                    new_nosy.add(recipient)
+
+    if current_nosy != new_nosy:
+        # that's it, save off the new nosy list
+        newvalues['nosy'] = list(new_nosy)
+
+def init(db):
+    db.issue.react('create', nosyreaction)
+    db.issue.react('set', nosyreaction)
+    db.issue.audit('create', updatenosy)
+    db.issue.audit('set', updatenosy)