Merge pull request #136 from aroig/gh/label-fix

Fix issue with multiple instances of gmail labels header

offlineimap/folder/Base.py

@@ -401,6 +401,9 @@ class BaseFolder(object):
         """
         Adds new header to the provided message.
 
+        WARNING: This function is a bit tricky, and modifying it in the wrong way,
+        may easily lead to data-loss.
+
         Arguments:
         - content: message content, headers and body as a single string
         - linebreak: string that carries line ending
@@ -512,8 +515,8 @@ class BaseFolder(object):
 
     def getmessageheader(self, content, name):
         """
-        Searches for the given header and returns its value.
-        Header name is case-insensitive.
+        Searches for the first occurence of the given header and returns
+        its value. Header name is case-insensitive.
 
         Arguments:
         - contents: message itself
@@ -535,6 +538,27 @@ class BaseFolder(object):
             return None
 
 
+    def getmessageheaderlist(self, content, name):
+        """
+        Searches for the given header and returns a list of values for
+        that header.
+
+        Arguments:
+        - contents: message itself
+        - name: name of the header to be searched
+
+        Returns: list of header values or emptylist if no such header was found
+
+        """
+        self.ui.debug('', 'getmessageheaderlist: called to get %s' % name)
+        eoh = self.__find_eoh(content)
+        self.ui.debug('', 'getmessageheaderlist: eoh = %d' % eoh)
+        headers = content[0:eoh]
+        self.ui.debug('', 'getmessageheaderlist: headers = %s' % repr(headers))
+
+        return re.findall('^%s:(.*)$' % name, headers, flags = re.MULTILINE | re.IGNORECASE)
+
+
     def deletemessageheaders(self, content, header_list):
         """
         Deletes headers in the given list from the message content.

offlineimap/folder/Gmail.py

@@ -93,6 +93,10 @@ class GmailFolder(IMAPFolder):
                 labels = set()
             labels = labels - self.ignorelabels
             labels_str = imaputil.format_labels_string(self.labelsheader, sorted(labels))
+
+            # First remove old label headers that may be in the message content retrieved
+            # from gmail Then add a labels header with current gmail labels.
+            body = self.deletemessageheaders(body, self.labelsheader)
             body = self.addmessageheader(body, '\n', self.labelsheader, labels_str)
 
         if len(body)>200:
@@ -189,8 +193,9 @@ class GmailFolder(IMAPFolder):
         if not self.synclabels:
             return super(GmailFolder, self).savemessage(uid, content, flags, rtime)
 
-        labels = imaputil.labels_from_header(self.labelsheader,
-          self.getmessageheader(content, self.labelsheader))
+        labels = set()
+        for hstr in self.getmessageheaderlist(content, self.labelsheader):
+            labels.update(imaputil.labels_from_header(self.labelsheader, hstr))
 
         ret = super(GmailFolder, self).savemessage(uid, content, flags, rtime)
         self.savemessagelabels(ret, labels)

offlineimap/folder/GmailMaildir.py

@@ -87,9 +87,10 @@ class GmailMaildirFolder(MaildirFolder):
             content = file.read()
             file.close()
 
-            self.messagelist[uid]['labels'] = \
-              imaputil.labels_from_header(self.labelsheader,
-              self.getmessageheader(content, self.labelsheader))
+            self.messagelist[uid]['labels'] = set()
+            for hstr in self.getmessageheaderlist(content, self.labelsheader):
+                self.messagelist[uid]['labels'].update(
+                    imaputil.labels_from_header(self.labelsheader, hstr))
             self.messagelist[uid]['labels_cached'] = True
 
         return self.messagelist[uid]['labels']
@@ -111,8 +112,10 @@ class GmailMaildirFolder(MaildirFolder):
         if not self.synclabels:
             return super(GmailMaildirFolder, self).savemessage(uid, content, flags, rtime)
 
-        labels = imaputil.labels_from_header(self.labelsheader,
-          self.getmessageheader(content, self.labelsheader))
+        labels = set()
+        for hstr in self.getmessageheaderlist(content, self.labelsheader):
+            labels.update(imaputil.labels_from_header(self.labelsheader, hstr))
+
         ret = super(GmailMaildirFolder, self).savemessage(uid, content, flags, rtime)
 
         # Update the mtime and labels
@@ -135,9 +138,9 @@ class GmailMaildirFolder(MaildirFolder):
         content = file.read()
         file.close()
 
-        oldlabels = imaputil.labels_from_header(self.labelsheader,
-          self.getmessageheader(content, self.labelsheader))
-
+        oldlabels = set()
+        for hstr in self.getmessageheaderlist(content, self.labelsheader):
+            oldlabels.update(imaputil.labels_from_header(self.labelsheader, hstr))
 
         labels = labels - ignorelabels
         ignoredlabels = oldlabels & ignorelabels
@@ -150,7 +153,11 @@ class GmailMaildirFolder(MaildirFolder):
         # Change labels into content
         labels_str = imaputil.format_labels_string(self.labelsheader,
           sorted(labels | ignoredlabels))
+
+        # First remove old labels header, and then add the new one
+        content = self.deletemessageheaders(content, self.labelsheader)
         content = self.addmessageheader(content, '\n', self.labelsheader, labels_str)
+
         rtime = self.messagelist[uid].get('rtime', None)
 
         # write file with new labels to a unique file in tmp