Code

Extracted duplicated mail-sending code from mailgw, roundupdb and client.py to
[roundup.git] / roundup / roundupdb.py
index ab3e0f3de796c6aad5fc835f08c3656dff94e672..5bc4928a7af2e94a67591345661b6602e37d9a35 100644 (file)
 # BASIS, AND THERE IS NO OBLIGATION WHATSOEVER TO PROVIDE MAINTENANCE,
 # SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
 # 
-# $Id: roundupdb.py,v 1.16 2001-10-30 00:54:45 richard Exp $
+# $Id: roundupdb.py,v 1.89 2003-09-08 09:28:28 jlgijsbers Exp $
 
-import re, os, smtplib, socket
+__doc__ = """
+Extending hyperdb with types specific to issue-tracking.
+"""
 
-import hyperdb, date
+import re, os, smtplib, socket, time, random
+import cStringIO, base64, quopri, mimetypes
 
-class DesignatorError(ValueError):
-    pass
-def splitDesignator(designator, dre=re.compile(r'([^\d]+)(\d+)')):
-    ''' Take a foo123 and return ('foo', 123)
-    '''
-    m = dre.match(designator)
-    if m is None:
-        raise DesignatorError, '"%s" not a node designator'%designator
-    return m.group(1), m.group(2)
+from rfc2822 import encode_header
+
+from roundup import password, date, hyperdb
+
+# MessageSendError is imported for backwards compatibility
+from roundup.mailer import Mailer, straddr, MessageSendError
 
 class Database:
     def getuid(self):
@@ -37,209 +37,80 @@ class Database:
         that owns this connection to the hyperdatabase."""
         return self.user.lookup(self.journaltag)
 
-    def uidFromAddress(self, address, create=1):
-        ''' address is from the rfc822 module, and therefore is (name, addr)
-
-            user is created if they don't exist in the db already
-        '''
-        (realname, address) = address
-        users = self.user.stringFind(address=address)
-        for dummy in range(2):
-            if len(users) > 1:
-                # make sure we don't match the anonymous or admin user
-                for user in users:
-                    if user == '1': continue
-                    if self.user.get(user, 'username') == 'anonymous': continue
-                    # first valid match will do
-                    return user
-                # well, I guess we have no choice
-                return user[0]
-            elif users:
-                return users[0]
-            # try to match the username to the address (for local
-            # submissions where the address is empty)
-            users = self.user.stringFind(username=address)
-
-        # couldn't match address or username, so create a new user
-        return self.user.create(username=address, address=address,
-            realname=realname)
-
-_marker = []
-# XXX: added the 'creator' faked attribute
-class Class(hyperdb.Class):
-    # Overridden methods:
-    def __init__(self, db, classname, **properties):
-        if (properties.has_key('creation') or properties.has_key('activity')
-                or properties.has_key('creator')):
-            raise ValueError, '"creation", "activity" and "creator" are reserved'
-        hyperdb.Class.__init__(self, db, classname, **properties)
-        self.auditors = {'create': [], 'set': [], 'retire': []}
-        self.reactors = {'create': [], 'set': [], 'retire': []}
-
-    def create(self, **propvalues):
-        """These operations trigger detectors and can be vetoed.  Attempts
-        to modify the "creation" or "activity" properties cause a KeyError.
+    def getUserTimezone(self):
+        """Return user timezone defined in 'timezone' property of user class.
+        If no such property exists return 0
         """
-        if propvalues.has_key('creation') or propvalues.has_key('activity'):
-            raise KeyError, '"creation" and "activity" are reserved'
-        for audit in self.auditors['create']:
-            audit(self.db, self, None, propvalues)
-        nodeid = hyperdb.Class.create(self, **propvalues)
-        for react in self.reactors['create']:
-            react(self.db, self, nodeid, None)
-        return nodeid
-
-    def set(self, nodeid, **propvalues):
-        """These operations trigger detectors and can be vetoed.  Attempts
-        to modify the "creation" or "activity" properties cause a KeyError.
-        """
-        if propvalues.has_key('creation') or propvalues.has_key('activity'):
-            raise KeyError, '"creation" and "activity" are reserved'
-        for audit in self.auditors['set']:
-            audit(self.db, self, nodeid, propvalues)
-        oldvalues = self.db.getnode(self.classname, nodeid)
-        hyperdb.Class.set(self, nodeid, **propvalues)
-        for react in self.reactors['set']:
-            react(self.db, self, nodeid, oldvalues)
-
-    def retire(self, nodeid):
-        """These operations trigger detectors and can be vetoed.  Attempts
-        to modify the "creation" or "activity" properties cause a KeyError.
-        """
-        for audit in self.auditors['retire']:
-            audit(self.db, self, nodeid, None)
-        hyperdb.Class.retire(self, nodeid)
-        for react in self.reactors['retire']:
-            react(self.db, self, nodeid, None)
-
-    def get(self, nodeid, propname, default=_marker):
-        """Attempts to get the "creation" or "activity" properties should
-        do the right thing.
-        """
-        if propname == 'creation':
-            journal = self.db.getjournal(self.classname, nodeid)
-            if journal:
-                return self.db.getjournal(self.classname, nodeid)[0][1]
-            else:
-                # on the strange chance that there's no journal
-                return date.Date()
-        if propname == 'activity':
-            journal = self.db.getjournal(self.classname, nodeid)
-            if journal:
-                return self.db.getjournal(self.classname, nodeid)[-1][1]
-            else:
-                # on the strange chance that there's no journal
-                return date.Date()
-        if propname == 'creator':
-            journal = self.db.getjournal(self.classname, nodeid)
-            if journal:
-                name = self.db.getjournal(self.classname, nodeid)[0][2]
-            else:
-                return None
-            return self.db.user.lookup(name)
-        if default is not _marker:
-            return hyperdb.Class.get(self, nodeid, propname, default)
+        userid = self.getuid()
+        try:
+            timezone = int(self.user.get(userid, 'timezone'))
+        except (KeyError, ValueError, TypeError):
+            # If there is no class 'user' or current user doesn't have timezone 
+            # property or that property is not numeric assume he/she lives in 
+            # Greenwich :)
+            timezone = 0
+        return timezone
+
+    def figure_curuserid(self):
+        """Figure out the 'curuserid'."""
+        if self.journaltag is None:
+            self.curuserid = None
+        elif self.journaltag == 'admin':
+            # admin user may not exist, but always has ID 1
+            self.curuserid = '1'
         else:
-            return hyperdb.Class.get(self, nodeid, propname)
-
-    def getprops(self, protected=1):
-        """In addition to the actual properties on the node, these
-        methods provide the "creation" and "activity" properties. If the
-        "protected" flag is true, we include protected properties - those
-        which may not be modified.
-        """
-        d = hyperdb.Class.getprops(self, protected=protected).copy()
-        if protected:
-            d['creation'] = hyperdb.Date()
-            d['activity'] = hyperdb.Date()
-            d['creator'] = hyperdb.Link("user")
-        return d
-
-    #
-    # Detector interface
-    #
-    def audit(self, event, detector):
-        """Register a detector
-        """
-        self.auditors[event].append(detector)
-
-    def react(self, event, detector):
-        """Register a detector
-        """
-        self.reactors[event].append(detector)
-
-
-class FileClass(Class):
-    def create(self, **propvalues):
-        ''' snaffle the file propvalue and store in a file
-        '''
-        content = propvalues['content']
-        del propvalues['content']
-        newid = Class.create(self, **propvalues)
-        self.setcontent(self.classname, newid, content)
-        return newid
-
-    def filename(self, classname, nodeid):
-        # TODO: split into multiple files directories
-        return os.path.join(self.db.dir, 'files', '%s%s'%(classname, nodeid))
-
-    def setcontent(self, classname, nodeid, content):
-        ''' set the content file for this file
-        '''
-        open(self.filename(classname, nodeid), 'wb').write(content)
+            self.curuserid = self.user.lookup(self.journaltag)
+
+    def confirm_registration(self, otk):
+        props = self.otks.getall(otk)
+        for propname, proptype in self.user.getprops().items():
+            value = props.get(propname, None)
+            if value is None:
+                pass
+            elif isinstance(proptype, hyperdb.Date):
+                props[propname] = date.Date(value)
+            elif isinstance(proptype, hyperdb.Interval):
+                props[propname] = date.Interval(value)
+            elif isinstance(proptype, hyperdb.Password):
+                props[propname] = password.Password()
+                props[propname].unpack(value)
+
+        # tag new user creation with 'admin'
+        self.journaltag = 'admin'
+        self.figure_curuserid()
+
+        # create the new user
+        cl = self.user
+      
+        props['roles'] = self.config.NEW_WEB_USER_ROLES
+        del props['__time']
+        userid = cl.create(**props)
+        # clear the props from the otk database
+        self.otks.destroy(otk)
+        self.commit()
+        
+        return userid
 
-    def getcontent(self, classname, nodeid):
-        ''' get the content file for this file
-        '''
-        return open(self.filename(classname, nodeid), 'rb').read()
 
-    def get(self, nodeid, propname, default=_marker):
-        ''' trap the content propname and get it from the file
-        '''
-        if propname == 'content':
-            return self.getcontent(self.classname, nodeid)
-        if default is not _marker:
-            return Class.get(self, nodeid, propname, default)
-        else:
-            return Class.get(self, nodeid, propname)
+class DetectorError(RuntimeError):
+    """ Raised by detectors that want to indicate that something's amiss
+    """
+    pass
 
-    def getprops(self, protected=1):
-        ''' In addition to the actual properties on the node, these methods
-            provide the "content" property. If the "protected" flag is true,
-            we include protected properties - those which may not be
-            modified.
-        '''
-        d = Class.getprops(self, protected=protected).copy()
-        if protected:
-            d['content'] = hyperdb.String()
-        return d
-
-# XXX deviation from spec - was called ItemClass
-class IssueClass(Class):
-    # configuration
-    MESSAGES_TO_AUTHOR = 'no'
-
-    # Overridden methods:
-
-    def __init__(self, db, classname, **properties):
-        """The newly-created class automatically includes the "messages",
-        "files", "nosy", and "superseder" properties.  If the 'properties'
-        dictionary attempts to specify any of these properties or a
-        "creation" or "activity" property, a ValueError is raised."""
-        if not properties.has_key('title'):
-            properties['title'] = hyperdb.String()
-        if not properties.has_key('messages'):
+# deviation from spec - was called IssueClass
+class IssueClass:
+    """ This class is intended to be mixed-in with a hyperdb backend
+        implementation. The backend should provide a mechanism that
+        enforces the title, messages, files, nosy and superseder
+        properties:
+            properties['title'] = hyperdb.String(indexme='yes')
             properties['messages'] = hyperdb.Multilink("msg")
-        if not properties.has_key('files'):
             properties['files'] = hyperdb.Multilink("file")
-        if not properties.has_key('nosy'):
             properties['nosy'] = hyperdb.Multilink("user")
-        if not properties.has_key('superseder'):
             properties['superseder'] = hyperdb.Multilink(classname)
-        Class.__init__(self, db, classname, **properties)
+    """
 
     # New methods:
-
     def addmessage(self, nodeid, summary, text):
         """Add a message to an issue's mail spool.
 
@@ -253,152 +124,368 @@ class IssueClass(Class):
         appended to the "messages" field of the specified issue.
         """
 
-    def sendmessage(self, nodeid, msgid):
+    # XXX "bcc" is an optional extra here...
+    def nosymessage(self, nodeid, msgid, oldvalues, whichnosy='nosy',
+            from_address=None, cc=[]): #, bcc=[]):
         """Send a message to the members of an issue's nosy list.
 
         The message is sent only to users on the nosy list who are not
         already on the "recipients" list for the message.
         
         These users are then added to the message's "recipients" list.
+
         """
+        users = self.db.user
+        messages = self.db.msg
+
         # figure the recipient ids
-        recipients = self.db.msg.get(msgid, 'recipients')
+        sendto = []
         r = {}
-        for recipid in recipients:
+        recipients = messages.get(msgid, 'recipients')
+        for recipid in messages.get(msgid, 'recipients'):
             r[recipid] = 1
 
         # figure the author's id, and indicate they've received the message
-        authid = self.db.msg.get(msgid, 'author')
+        authid = messages.get(msgid, 'author')
+
+        # possibly send the message to the author, as long as they aren't
+        # anonymous
+        if (users.get(authid, 'username') != 'anonymous' and
+                not r.has_key(authid)):
+            if (self.db.config.MESSAGES_TO_AUTHOR == 'yes' or
+                (self.db.config.MESSAGES_TO_AUTHOR == 'new' and not oldvalues)):
+                # make sure they have an address
+                add = users.get(authid, 'address')
+                if add:
+                    # send it to them
+                    sendto.append(add)
+                    recipients.append(authid)
+
         r[authid] = 1
 
-        sendto = []
-        # ... but duplicate the message to the author as long as it's not
-        # the anonymous user
-        if (self.MESSAGES_TO_AUTHOR == 'yes' and
-                self.db.user.get(authid, 'username') != 'anonymous'):
-            sendto.append(authid)
+        # now deal with cc people.
+        for cc_userid in cc :
+            if r.has_key(cc_userid):
+                continue
+            # make sure they have an address
+            add = users.get(cc_userid, 'address')
+            if add:
+                # send it to them
+                sendto.append(add)
+                recipients.append(cc_userid)
 
         # now figure the nosy people who weren't recipients
-        nosy = self.get(nodeid, 'nosy')
+        nosy = self.get(nodeid, whichnosy)
         for nosyid in nosy:
             # Don't send nosy mail to the anonymous user (that user
             # shouldn't appear in the nosy list, but just in case they
             # do...)
-            if self.db.user.get(nosyid, 'username') == 'anonymous': continue
+            if users.get(nosyid, 'username') == 'anonymous':
+                continue
+            # make sure they haven't seen the message already
             if not r.has_key(nosyid):
-                sendto.append(nosyid)
-                recipients.append(nosyid)
+                # make sure they have an address
+                add = users.get(nosyid, 'address')
+                if add:
+                    # send it to them
+                    sendto.append(add)
+                    recipients.append(nosyid)
+
+        # generate a change note
+        if oldvalues:
+            note = self.generateChangeNote(nodeid, oldvalues)
+        else:
+            note = self.generateCreateNote(nodeid)
 
+        # we have new recipients
         if sendto:
             # update the message's recipients list
-            self.db.msg.set(msgid, recipients=recipients)
-
-            # send an email to the people who missed out
-            sendto = [self.db.user.get(i, 'address') for i in recipients]
-            cn = self.classname
-            title = self.get(nodeid, 'title') or '%s message copy'%cn
-            # figure author information
-            authname = self.db.user.get(authid, 'realname')
-            if not authname:
-                authname = self.db.user.get(authid, 'username')
-            authaddr = self.db.user.get(authid, 'address')
-            if authaddr:
-                authaddr = '<%s> '%authaddr
-            else:
-                authaddr = ''
-            # TODO attachments
-            m = ['Subject: [%s%s] %s'%(cn, nodeid, title)]
-            m.append('To: %s'%', '.join(sendto))
-            m.append('From: %s'%self.ISSUE_TRACKER_EMAIL)
-            m.append('Reply-To: %s'%self.ISSUE_TRACKER_EMAIL)
-            m.append('')
-            # add author information
-            m.append("%s %sadded the comment:"%(authname, authaddr))
-            m.append('')
-            # add the content
-            m.append(self.db.msg.get(msgid, 'content'))
-            # "list information" footer
-            m.append(self.email_footer(nodeid, msgid))
-            try:
-                smtp = smtplib.SMTP(self.MAILHOST)
-                smtp.sendmail(self.ISSUE_TRACKER_EMAIL, sendto, '\n'.join(m))
-            except socket.error, value:
-                return "Couldn't send confirmation email: mailhost %s"%value
-            except smtplib.SMTPException, value:
-                return "Couldn't send confirmation email: %s"%value
-
-    def email_footer(self, nodeid, msgid):
-        ''' Add a footer to the e-mail with some useful information
+            messages.set(msgid, recipients=recipients)
+
+            # send the message
+            self.send_message(nodeid, msgid, note, sendto, from_address)
+
+    # backwards compatibility - don't remove
+    sendmessage = nosymessage
+
+    def send_message(self, nodeid, msgid, note, sendto, from_address=None):
+        '''Actually send the nominated message from this node to the sendto
+           recipients, with the note appended.
         '''
-        web = self.ISSUE_TRACKER_WEB
-        return '''%s
-Roundup issue tracker
-%s
-%s
-'''%('_'*len(web), self.ISSUE_TRACKER_EMAIL, web)
+        users = self.db.user
+        messages = self.db.msg
+        files = self.db.file
+
+        # determine the messageid and inreplyto of the message
+        inreplyto = messages.get(msgid, 'inreplyto')
+        messageid = messages.get(msgid, 'messageid')
+
+        # make up a messageid if there isn't one (web edit)
+        if not messageid:
+            # this is an old message that didn't get a messageid, so
+            # create one
+            messageid = "<%s.%s.%s%s@%s>"%(time.time(), random.random(),
+                self.classname, nodeid, self.db.config.MAIL_DOMAIN)
+            messages.set(msgid, messageid=messageid)
+
+        # send an email to the people who missed out
+        cn = self.classname
+        title = self.get(nodeid, 'title') or '%s message copy'%cn
+        # figure author information
+        authid = messages.get(msgid, 'author')
+        authname = users.get(authid, 'realname')
+        if not authname:
+            authname = users.get(authid, 'username')
+        authaddr = users.get(authid, 'address')
+        if authaddr:
+            authaddr = " <%s>" % straddr( ('',authaddr) )
+        else:
+            authaddr = ''
+
+        # make the message body
+        m = ['']
+
+        # put in roundup's signature
+        if self.db.config.EMAIL_SIGNATURE_POSITION == 'top':
+            m.append(self.email_signature(nodeid, msgid))
+
+        # add author information
+        if len(self.get(nodeid,'messages')) == 1:
+            m.append("New submission from %s%s:"%(authname, authaddr))
+        else:
+            m.append("%s%s added the comment:"%(authname, authaddr))
+        m.append('')
+
+        # add the content
+        m.append(messages.get(msgid, 'content'))
+
+        # add the change note
+        if note:
+            m.append(note)
+
+        # put in roundup's signature
+        if self.db.config.EMAIL_SIGNATURE_POSITION == 'bottom':
+            m.append(self.email_signature(nodeid, msgid))
+
+        # encode the content as quoted-printable
+        content = cStringIO.StringIO('\n'.join(m))
+        content_encoded = cStringIO.StringIO()
+        quopri.encode(content, content_encoded, 0)
+        content_encoded = content_encoded.getvalue()
+
+        # get the files for this message
+        message_files = messages.get(msgid, 'files')
+
+        # make sure the To line is always the same (for testing mostly)
+        sendto.sort()
+
+        # make sure we have a from address
+        if from_address is None:
+            from_address = self.db.config.TRACKER_EMAIL
+
+        # additional bit for after the From: "name"
+        from_tag = getattr(self.db.config, 'EMAIL_FROM_TAG', '')
+        if from_tag:
+            from_tag = ' ' + from_tag
+
+        subject = '[%s%s] %s' % (cn, nodeid, encode_header(title))
+        author = straddr((encode_header(authname) + from_tag, from_address))
+
+        # create the message
+        mailer = Mailer(self.db.config)
+        message, writer = mailer.get_standard_message(', '.join(sendto),
+                                                      subject, author)
+
+        tracker_name = encode_header(self.db.config.TRACKER_NAME)
+        writer.addheader('Reply-To', straddr((tracker_name, from_address)))
+        if messageid:
+            writer.addheader('Message-Id', messageid)
+        if inreplyto:
+            writer.addheader('In-Reply-To', inreplyto)
+
+        # attach files
+        if message_files:
+            part = writer.startmultipartbody('mixed')
+            part = writer.nextpart()
+            part.addheader('Content-Transfer-Encoding', 'quoted-printable')
+            body = part.startbody('text/plain; charset=utf-8')
+            body.write(content_encoded)
+            for fileid in message_files:
+                name = files.get(fileid, 'name')
+                mime_type = files.get(fileid, 'type')
+                content = files.get(fileid, 'content')
+                part = writer.nextpart()
+                if mime_type == 'text/plain':
+                    part.addheader('Content-Disposition',
+                        'attachment;\n filename="%s"'%name)
+                    part.addheader('Content-Transfer-Encoding', '7bit')
+                    body = part.startbody('text/plain')
+                    body.write(content)
+                else:
+                    # some other type, so encode it
+                    if not mime_type:
+                        # this should have been done when the file was saved
+                        mime_type = mimetypes.guess_type(name)[0]
+                    if mime_type is None:
+                        mime_type = 'application/octet-stream'
+                    part.addheader('Content-Disposition',
+                        'attachment;\n filename="%s"'%name)
+                    part.addheader('Content-Transfer-Encoding', 'base64')
+                    body = part.startbody(mime_type)
+                    body.write(base64.encodestring(content))
+            writer.lastpart()
+        else:
+            writer.addheader('Content-Transfer-Encoding', 'quoted-printable')
+            body = writer.startbody('text/plain; charset=utf-8')
+            body.write(content_encoded)
+
+        mailer.smtp_send(sendto, message)
+
+    def email_signature(self, nodeid, msgid):
+        ''' Add a signature to the e-mail with some useful information
+        '''
+        # simplistic check to see if the url is valid,
+        # then append a trailing slash if it is missing
+        base = self.db.config.TRACKER_WEB 
+        if (not isinstance(base , type('')) or
+            not (base.startswith('http://') or base.startswith('https://'))):
+            base = "Configuration Error: TRACKER_WEB isn't a " \
+                "fully-qualified URL"
+        elif base[-1] != '/' :
+            base += '/'
+        web = base + self.classname + nodeid
+
+        # ensure the email address is properly quoted
+        email = straddr((self.db.config.TRACKER_NAME,
+            self.db.config.TRACKER_EMAIL))
+
+        line = '_' * max(len(web)+2, len(email))
+        return '%s\n%s\n<%s>\n%s'%(line, email, web, line)
+
+
+    def generateCreateNote(self, nodeid):
+        """Generate a create note that lists initial property values
+        """
+        cn = self.classname
+        cl = self.db.classes[cn]
+        props = cl.getprops(protected=0)
+
+        # list the values
+        m = []
+        l = props.items()
+        l.sort()
+        for propname, prop in l:
+            value = cl.get(nodeid, propname, None)
+            # skip boring entries
+            if not value:
+                continue
+            if isinstance(prop, hyperdb.Link):
+                link = self.db.classes[prop.classname]
+                if value:
+                    key = link.labelprop(default_to_id=1)
+                    if key:
+                        value = link.get(value, key)
+                else:
+                    value = ''
+            elif isinstance(prop, hyperdb.Multilink):
+                if value is None: value = []
+                l = []
+                link = self.db.classes[prop.classname]
+                key = link.labelprop(default_to_id=1)
+                if key:
+                    value = [link.get(entry, key) for entry in value]
+                value.sort()
+                value = ', '.join(value)
+            m.append('%s: %s'%(propname, value))
+        m.insert(0, '----------')
+        m.insert(0, '')
+        return '\n'.join(m)
+
+    def generateChangeNote(self, nodeid, oldvalues):
+        """Generate a change note that lists property changes
+        """
+        if __debug__ :
+            if not isinstance(oldvalues, type({})) :
+                raise TypeError("'oldvalues' must be dict-like, not %s."%
+                    type(oldvalues))
+
+        cn = self.classname
+        cl = self.db.classes[cn]
+        changed = {}
+        props = cl.getprops(protected=0)
+
+        # determine what changed
+        for key in oldvalues.keys():
+            if key in ['files','messages']:
+                continue
+            if key in ('activity', 'creator', 'creation'):
+                continue
+            new_value = cl.get(nodeid, key)
+            # the old value might be non existent
+            try:
+                old_value = oldvalues[key]
+                if type(new_value) is type([]):
+                    new_value.sort()
+                    old_value.sort()
+                if new_value != old_value:
+                    changed[key] = old_value
+            except:
+                changed[key] = new_value
+
+        # list the changes
+        m = []
+        l = changed.items()
+        l.sort()
+        for propname, oldvalue in l:
+            prop = props[propname]
+            value = cl.get(nodeid, propname, None)
+            if isinstance(prop, hyperdb.Link):
+                link = self.db.classes[prop.classname]
+                key = link.labelprop(default_to_id=1)
+                if key:
+                    if value:
+                        value = link.get(value, key)
+                    else:
+                        value = ''
+                    if oldvalue:
+                        oldvalue = link.get(oldvalue, key)
+                    else:
+                        oldvalue = ''
+                change = '%s -> %s'%(oldvalue, value)
+            elif isinstance(prop, hyperdb.Multilink):
+                change = ''
+                if value is None: value = []
+                if oldvalue is None: oldvalue = []
+                l = []
+                link = self.db.classes[prop.classname]
+                key = link.labelprop(default_to_id=1)
+                # check for additions
+                for entry in value:
+                    if entry in oldvalue: continue
+                    if key:
+                        l.append(link.get(entry, key))
+                    else:
+                        l.append(entry)
+                if l:
+                    l.sort()
+                    change = '+%s'%(', '.join(l))
+                    l = []
+                # check for removals
+                for entry in oldvalue:
+                    if entry in value: continue
+                    if key:
+                        l.append(link.get(entry, key))
+                    else:
+                        l.append(entry)
+                if l:
+                    l.sort()
+                    change += ' -%s'%(', '.join(l))
+            else:
+                change = '%s -> %s'%(oldvalue, value)
+            m.append('%s: %s'%(propname, change))
+        if m:
+            m.insert(0, '----------')
+            m.insert(0, '')
+        return '\n'.join(m)
 
-#
-# $Log: not supported by cvs2svn $
-# Revision 1.15  2001/10/23 01:00:18  richard
-# Re-enabled login and registration access after lopping them off via
-# disabling access for anonymous users.
-# Major re-org of the htmltemplate code, cleaning it up significantly. Fixed
-# a couple of bugs while I was there. Probably introduced a couple, but
-# things seem to work OK at the moment.
-#
-# Revision 1.14  2001/10/21 07:26:35  richard
-# feature #473127: Filenames. I modified the file.index and htmltemplate
-#  source so that the filename is used in the link and the creation
-#  information is displayed.
-#
-# Revision 1.13  2001/10/21 00:45:15  richard
-# Added author identification to e-mail messages from roundup.
-#
-# Revision 1.12  2001/10/04 02:16:15  richard
-# Forgot to pass the protected flag down *sigh*.
-#
-# Revision 1.11  2001/10/04 02:12:42  richard
-# Added nicer command-line item adding: passing no arguments will enter an
-# interactive more which asks for each property in turn. While I was at it, I
-# fixed an implementation problem WRT the spec - I wasn't raising a
-# ValueError if the key property was missing from a create(). Also added a
-# protected=boolean argument to getprops() so we can list only the mutable
-# properties (defaults to yes, which lists the immutables).
-#
-# Revision 1.10  2001/08/07 00:24:42  richard
-# stupid typo
-#
-# Revision 1.9  2001/08/07 00:15:51  richard
-# Added the copyright/license notice to (nearly) all files at request of
-# Bizar Software.
-#
-# Revision 1.8  2001/08/02 06:38:17  richard
-# Roundupdb now appends "mailing list" information to its messages which
-# include the e-mail address and web interface address. Templates may
-# override this in their db classes to include specific information (support
-# instructions, etc).
-#
-# Revision 1.7  2001/07/30 02:38:31  richard
-# get() now has a default arg - for migration only.
-#
-# Revision 1.6  2001/07/30 00:05:54  richard
-# Fixed IssueClass so that superseders links to its classname rather than
-# hard-coded to "issue".
-#
-# Revision 1.5  2001/07/29 07:01:39  richard
-# Added vim command to all source so that we don't get no steenkin' tabs :)
-#
-# Revision 1.4  2001/07/29 04:05:37  richard
-# Added the fabricated property "id".
-#
-# Revision 1.3  2001/07/23 07:14:41  richard
-# Moved the database backends off into backends.
-#
-# Revision 1.2  2001/07/22 12:09:32  richard
-# Final commit of Grande Splite
-#
-# Revision 1.1  2001/07/22 11:58:35  richard
-# More Grande Splite
-#
-#
 # vim: set filetype=python ts=4 sw=4 et si