Very limited support for SEARCH Commands. Closes: #4209

limited to HEADER Message-ID.

This is a quick workaround for avoiding duplicate saves in Drafts Folder.
but we'll get there!

4 files changed, 137 insertions, 17 deletions

diff --git a/mail/changes/feature_enable-search-by-msg-id b/mail/changes/feature_enable-search-by-msg-id
new file mode 100644
index 0000000..accc12f
--- /dev/null
+++ b/mail/changes/feature_enable-search-by-msg-id
@@ -0,0 +1,3 @@
+  o Ability to support SEARCH Commands, limited to HEADER Message-ID.
+    This is a quick workaround for avoiding duplicate saves in Drafts Folder.
+    Closes: #4209
diff --git a/mail/src/leap/mail/imap/fields.py b/mail/src/leap/mail/imap/fields.py
index 70af61f..3d2ac92 100644
--- a/mail/src/leap/mail/imap/fields.py
+++ b/mail/src/leap/mail/imap/fields.py
@@ -45,13 +45,12 @@ class WithMsgFields(object):
     HEADERS_KEY = "headers"
     DATE_KEY = "date"
     SUBJECT_KEY = "subject"
-    # XXX DELETE-ME
-    #NUM_PARTS_KEY = "numparts"  # not needed?!
     PARTS_MAP_KEY = "part_map"
     BODY_KEY = "body"  # link to phash of body
+    MSGID_KEY = "msgid"
 
     # content
-    LINKED_FROM_KEY = "lkf"
+    LINKED_FROM_KEY = "lkf"  # XXX not implemented yet!
     RAW_KEY = "raw"
     CTYPE_KEY = "ctype"
 
@@ -69,10 +68,6 @@ class WithMsgFields(object):
     TYPE_HEADERS_VAL = "head"
     TYPE_CONTENT_VAL = "cnt"
 
-    # XXX DEPRECATE
-    #TYPE_MESSAGE_VAL = "msg"
-    #TYPE_ATTACHMENT_VAL = "attach"
-
     INBOX_VAL = "inbox"
 
     # Flags in Mailbox and Message
@@ -96,6 +91,7 @@ class WithMsgFields(object):
     TYPE_MBOX_IDX = 'by-type-and-mbox'
     TYPE_MBOX_UID_IDX = 'by-type-and-mbox-and-uid'
     TYPE_SUBS_IDX = 'by-type-and-subscribed'
+    TYPE_MSGID_IDX = 'by-type-and-message-id'
     TYPE_MBOX_SEEN_IDX = 'by-type-and-mbox-and-seen'
     TYPE_MBOX_RECT_IDX = 'by-type-and-mbox-and-recent'
     TYPE_MBOX_DEL_IDX = 'by-type-and-mbox-and-deleted'
@@ -125,6 +121,9 @@ class WithMsgFields(object):
         # fdocs uniqueness
         TYPE_MBOX_C_HASH_IDX: [KTYPE, MBOX_VAL, CHASH_VAL],
 
+        # headers doc - search by msgid.
+        TYPE_MSGID_IDX: [KTYPE, MSGID_KEY],
+
         # content, headers doc
         TYPE_C_HASH_IDX: [KTYPE, CHASH_VAL],
 
diff --git a/mail/src/leap/mail/imap/mailbox.py b/mail/src/leap/mail/imap/mailbox.py
index c9e8684..ccbf5c2 100644
--- a/mail/src/leap/mail/imap/mailbox.py
+++ b/mail/src/leap/mail/imap/mailbox.py
@@ -39,6 +39,7 @@ from leap.mail.decorators import deferred
 from leap.mail.imap.fields import WithMsgFields, fields
 from leap.mail.imap.messages import MessageCollection
 from leap.mail.imap.parser import MBoxParser
+from leap.mail.utils import first
 
 logger = logging.getLogger(__name__)
 
@@ -55,6 +56,7 @@ class SoledadMailbox(WithMsgFields, MBoxParser):
         imap4.IMailbox,
         imap4.IMailboxInfo,
         imap4.ICloseableMailbox,
+        imap4.ISearchableMailbox,
         imap4.IMessageCopier)
 
     # XXX should finish the implementation of IMailboxListener
@@ -617,6 +619,49 @@ class SoledadMailbox(WithMsgFields, MBoxParser):
         self._signal_unread_to_ui()
         return result
 
+    # ISearchableMailbox
+
+    def search(self, query, uid):
+        """
+        Search for messages that meet the given query criteria.
+
+        Warning: this is half-baked, and it might give problems since
+        it offers the SearchableInterface.
+        We'll be implementing it asap.
+
+        :param query: The search criteria
+        :type query: list
+
+        :param uid: If true, the IDs specified in the query are UIDs;
+                    otherwise they are message sequence IDs.
+        :type uid: bool
+
+        :return: A list of message sequence numbers or message UIDs which
+                 match the search criteria or a C{Deferred} whose callback
+                 will be invoked with such a list.
+        :rtype: C{list} or C{Deferred}
+        """
+        # TODO see if we can raise w/o interrupting flow
+        #:raise IllegalQueryError: Raised when query is not valid.
+        # example query:
+        #  ['UNDELETED', 'HEADER', 'Message-ID',
+        #   '52D44F11.9060107@dev.bitmask.net']
+
+        # TODO hardcoding for now! -- we'll support generic queries later on
+        # but doing a quickfix for avoiding duplicat saves in the draft folder.
+        # See issue #4209
+
+        if query[1] == 'HEADER' and query[2].lower() == "message-id":
+            msgid = str(query[3]).strip()
+            d = self.messages._get_uid_from_msgid(str(msgid))
+            d1 = defer.gatherResults([d])
+            # we want a list, so return it all the same
+            return d1
+
+        # nothing implemented for any other query
+        logger.warning("Cannot process query: %s" % (query,))
+        return []
+
     # IMessageCopier
 
     @deferred
diff --git a/mail/src/leap/mail/imap/messages.py b/mail/src/leap/mail/imap/messages.py
index 7b49c80..a3d29d6 100644
--- a/mail/src/leap/mail/imap/messages.py
+++ b/mail/src/leap/mail/imap/messages.py
@@ -20,6 +20,8 @@ LeapMessage and MessageCollection.
 import copy
 import logging
 import re
+import threading
+import time
 import StringIO
 
 from collections import defaultdict, namedtuple
@@ -44,6 +46,7 @@ from leap.mail.messageflow import IMessageConsumer, MessageProducer
 
 logger = logging.getLogger(__name__)
 
+read_write_lock = threading.Lock()
 
 # TODO ------------------------------------------------------------
 
@@ -53,6 +56,7 @@ logger = logging.getLogger(__name__)
 # [ ] Send patch to twisted for bug in imap4.py:5717  (content-type can be
 #     none? lower-case?)
 
+
 def lowerdict(_dict):
     """
     Return a dict with the keys in lowercase.
@@ -60,12 +64,17 @@ def lowerdict(_dict):
     :param _dict: the dict to convert
     :rtype: dict
     """
+    # TODO should properly implement a CaseInsensitive dict.
+    # Look into requests code.
     return dict((key.lower(), value)
                 for key, value in _dict.items())
 
 
 CHARSET_PATTERN = r"""charset=([\w-]+)"""
+MSGID_PATTERN = r"""<([\w@.]+)>"""
+
 CHARSET_RE = re.compile(CHARSET_PATTERN, re.IGNORECASE)
+MSGID_RE = re.compile(MSGID_PATTERN)
 
 
 class MessagePart(object):
@@ -897,6 +906,7 @@ class MessageCollection(WithMsgFields, IndexedDB, MailParser, MBoxParser):
     Implements a filter query over the messages contained in a soledad
     database.
     """
+
     # XXX this should be able to produce a MessageSet methinks
     # could validate these kinds of objects turning them
     # into a template for the class.
@@ -1044,9 +1054,14 @@ class MessageCollection(WithMsgFields, IndexedDB, MailParser, MBoxParser):
             newline = "\n%s: " % (k,)
             headers[k] = newline.join(v)
 
+        lower_headers = lowerdict(headers)
+        msgid = first(MSGID_RE.findall(
+            lower_headers.get('message-id', '')))
+
         hd = self._get_empty_doc(self.HEADERS_DOC)
         hd[self.CONTENT_HASH_KEY] = chash
         hd[self.HEADERS_KEY] = headers
+        hd[self.MSGID_KEY] = msgid
 
         if not subject and self.SUBJECT_FIELD in headers:
             hd[self.SUBJECT_KEY] = first(headers[self.SUBJECT_FIELD])
@@ -1139,16 +1154,17 @@ class MessageCollection(WithMsgFields, IndexedDB, MailParser, MBoxParser):
         logger.debug('enqueuing message docs for write')
         ptuple = SoledadWriterPayload
 
-        # first, regular docs: flags and headers
-        for doc in docs:
-            self.soledad_writer.put(ptuple(
-                mode=ptuple.CREATE, payload=doc))
+        with read_write_lock:
+            # first, regular docs: flags and headers
+            for doc in docs:
+                self.soledad_writer.put(ptuple(
+                    mode=ptuple.CREATE, payload=doc))
 
-        # and last, but not least, try to create
-        # content docs if not already there.
-        for cd in cdocs:
-            self.soledad_writer.put(ptuple(
-                mode=ptuple.CONTENT_CREATE, payload=cd))
+            # and last, but not least, try to create
+            # content docs if not already there.
+            for cd in cdocs:
+                self.soledad_writer.put(ptuple(
+                    mode=ptuple.CONTENT_CREATE, payload=cd))
 
     def _remove_cb(self, result):
         return result
@@ -1174,7 +1190,7 @@ class MessageCollection(WithMsgFields, IndexedDB, MailParser, MBoxParser):
         d.addCallback(self._remove_cb)
         return d
 
-    # getters
+    # getters: specific queries
 
     def _get_fdoc_from_chash(self, chash):
         """
@@ -1201,6 +1217,63 @@ class MessageCollection(WithMsgFields, IndexedDB, MailParser, MBoxParser):
         except Exception as exc:
             logger.exception("Unhandled error %r" % exc)
 
+    def _get_uid_from_msgidCb(self, msgid):
+        hdoc = None
+        with read_write_lock:
+            try:
+                query = self._soledad.get_from_index(
+                    fields.TYPE_MSGID_IDX,
+                    fields.TYPE_HEADERS_VAL, msgid)
+                if query:
+                    if len(query) > 1:
+                        logger.warning(
+                            "More than one hdoc found for this msgid, "
+                            "we got a duplicate!!")
+                        # XXX we could take action, like trigger a background
+                        # process to kill dupes.
+                    hdoc = query.pop()
+            except Exception as exc:
+                logger.exception("Unhandled error %r" % exc)
+
+        if hdoc is None:
+            logger.warning("Could not find hdoc for msgid %s"
+                           % (msgid,))
+            return None
+        msg_chash = hdoc.content.get(fields.CONTENT_HASH_KEY)
+        fdoc = self._get_fdoc_from_chash(msg_chash)
+        if not fdoc:
+            logger.warning("Could not find fdoc for msgid %s"
+                           % (msgid,))
+            return None
+        return fdoc.content.get(fields.UID_KEY, None)
+
+    @deferred
+    def _get_uid_from_msgid(self, msgid):
+        """
+        Return a UID for a given message-id.
+
+        It first gets the headers-doc for that msg-id, and
+        it found it queries the flags doc for the current mailbox
+        for the matching content-hash.
+
+        :return: A UID, or None
+        """
+        # We need to wait a little bit, cause in some of the cases
+        # the query is received right after we've saved the document,
+        # and we cannot find it otherwise. This seems to be enough.
+
+        # Doing a sleep since we'll be calling this in a secondary thread,
+        # but we'll should be able to collect the results after a
+        # reactor.callLater.
+        # Maybe we can implement something like NOT_DONE_YET in the web
+        # framework, and return from the callback?
+        # See: http://jcalderone.livejournal.com/50226.html
+        # reactor.callLater(0.3, self._get_uid_from_msgidCb, msgid)
+        time.sleep(0.3)
+        return self._get_uid_from_msgidCb(msgid)
+
+    # getters: generic for a mailbox
+
     def get_msg_by_uid(self, uid):
         """
         Retrieves a LeapMessage by UID.