Fixed a problem where members of a deleted mailing list were hanging around.

This would cause duplicate members (e.g. owners) if you created, deleted and
then recreated the mailing list.

Mailman.app.create -> Mailman.app.lifecycle; Mailman/doc/create.txt ->
Mailman/doc/lifecycle.txt; also added a remove_list() function.

Added SubscriptionError base class, made HostileSubscriptionError inherit from
that, and added a new AlreadySubscribedError.

Rewrote bin/rmlist to use the new lifecycle.remove_list() function.

IAddress.subscribe() must now throw an AlreadySubscribedError if the address
is already subscribed to the mailing list with the given role.

Added a Subscribers roster, attached to the IMailingList which gives access to
all subscribers of a mailing list, regardless of their role.  Added a new test
for this roster.

3 files changed, 23 insertions, 2 deletions

diff --git a/Mailman/database/model/address.py b/Mailman/database/model/address.py
index 9c36d2472..391004413 100644
--- a/Mailman/database/model/address.py
+++ b/Mailman/database/model/address.py
@@ -19,8 +19,10 @@ from elixir import *
 from email.utils import formataddr
 from zope.interface import implements
 
+from Mailman import Errors
 from Mailman.interfaces import IAddress
 
+
 MEMBER_KIND     = 'Mailman.database.model.member.Member'
 PREFERENCE_KIND = 'Mailman.database.model.preferences.Preferences'
 USER_KIND       = 'Mailman.database.model.user.User'
@@ -62,12 +64,18 @@ class Address(Entity):
             return '<Address: %s [%s] key: %s at %#x>' % (
                 address_str, verified, self.address, id(self))
 
-    def subscribe(self, mlist, role):
+    def subscribe(self, mailing_list, role):
         from Mailman.database.model import Member
         from Mailman.database.model import Preferences
         # This member has no preferences by default.
+        member = Member.get_by(role=role,
+                               mailing_list=mailing_list.fqdn_listname,
+                               address=self)
+        if member:
+            raise Errors.AlreadySubscribedError(
+                mailing_list.fqdn_listname, self.address, role)
         member = Member(role=role,
-                        mailing_list=mlist.fqdn_listname,
+                        mailing_list=mailing_list.fqdn_listname,
                         address=self)
         member.preferences = Preferences()
         return member
diff --git a/Mailman/database/model/mailinglist.py b/Mailman/database/model/mailinglist.py
index 11deb28c6..0cb968574 100644
--- a/Mailman/database/model/mailinglist.py
+++ b/Mailman/database/model/mailinglist.py
@@ -185,6 +185,7 @@ class MailingList(Entity):
         self.members = roster.MemberRoster(self)
         self.regular_members = roster.RegularMemberRoster(self)
         self.digest_members = roster.DigestMemberRoster(self)
+        self.subscribers = roster.Subscribers(self)
 
     @property
     def fqdn_listname(self):
diff --git a/Mailman/database/model/roster.py b/Mailman/database/model/roster.py
index 0730d2b4b..8440e0ffc 100644
--- a/Mailman/database/model/roster.py
+++ b/Mailman/database/model/roster.py
@@ -184,3 +184,15 @@ class DigestMemberRoster(AbstractRoster):
                                        role=MemberRole.member):
             if member.delivery_mode in _digest_modes:
                 yield member
+
+
+
+class Subscribers(AbstractRoster):
+    """Return all subscribed members regardless of their role."""
+
+    name = 'subscribers'
+
+    @property
+    def members(self):
+        for member in Member.select_by(mailing_list=self._mlist.fqdn_listname):
+            yield member