BibCatalog RT4 attachment handling

  * The output from the REST/1.0 interface has changed between rt3 and rt4
    Previously unnamed attachments would simply have an empty Name string.
    Now unnamed attachments result in the string '(Unnamed)'.
    Adjusting the regexp to handle both cases.

  * various code improvements along the way

modules/bibcatalog/lib/bibcatalog_system_rt.py

@@ -100,7 +100,7 @@ def ticket_search(self, uid, recordid=-1, subject="", text="", creator="",
            matching the subject, creator or owner of the ticket."""
 
         search_atoms = [] # the search expression will be made by and'ing these
-        if (recordid > -1):
+        if recordid > -1:
             #search by recid
             search_atoms.append("CF.{RecordID} = " + escape_shell_arg(str(recordid)))
         if subject:
@@ -337,7 +337,7 @@ def ticket_get_attribute(self, uid, ticketid, attribute):
             return ticinfo[attribute]
         return None
 
-    def ticket_get_info(self, uid, ticketid, attributes = None):
+    def ticket_get_info(self, uid, ticketid, attributes=None):
         """return ticket info as a dictionary of pre-defined attribute names.
            Or just those listed in attrlist.
            Returns None on failure"""
@@ -355,9 +355,9 @@ def ticket_get_info(self, uid, ticketid, attributes = None):
             return 0
 
         tdict = {}
-        for line in command_out.split("\n"):
-            if line.count(": ") > 0:
-                tattr, tvaluen = line.split(": ")[0], ": ".join(line.split(": ")[1:])
+        for line in command_out.splitlines():
+            if line.find(": ") > -1:
+                tattr, tvaluen = line.split(": ", 1)
                 tvalue = tvaluen.rstrip()
                 tdict[tattr] = tvalue
 
@@ -368,14 +368,29 @@ def ticket_get_info(self, uid, ticketid, attributes = None):
             return 0
 
         attachments = []
-        regex = re.compile(r"[0-9]*:\s{2}[(]")  # attachment's format: 557408:  (text/plain / 131b)
-        for line in command_out.split("\n"):
-            for match in regex.findall(line):
-                attachments.append(match.split(":")[0])
+
+        # attachment's format:
+        #     557408: (?:Name|\(Unnamed\))? (text/plain / 131b)
+        #  (Unnamed) is new in rt4, in rt3 no Name resulted in empty string,
+        #   hence 2 spaces
+        #
+        # example:
+        # id: ticket/443299/attachments
+        #
+        # Attachments: 1410963: (Unnamed) (multipart/alternative / 0b),
+        #              1410964: (Unnamed) (text/plain / 257b),
+        #              1410965: (Unnamed) (text/html / 2.9k),
+        #              1410966: (Unnamed) (text/plain / 534b)
+
+        attregex = re.compile(r"(?P<attachmentid>\d+):\s{1,2}[(\w]")
+        for line in command_out.splitlines():
+            amatch = attregex.search(line)
+            if amatch:
+                attachments.append(amatch.group('attachmentid'))
 
         # Query again for each attachment
-        for att in attachments:
-            command = CFG_BIBCATALOG_SYSTEM_RT_CLI + " show ticket/" + str(ticketid) + "/attachments/" + att
+        for attid in attachments:
+            command = "%s show ticket/%s/attachments/%s" % (CFG_BIBCATALOG_SYSTEM_RT_CLI, ticketid, attid)
             command_out = self._run_rt_command(command, uid)
             if command_out is None:
                 return 0
@@ -385,7 +400,7 @@ def ticket_get_info(self, uid, ticketid, attributes = None):
                     cstuff = line.split("Content: ")
                     tdict['Text'] = cstuff[1].rstrip()
 
-        if (len(tdict) > 0):
+        if len(tdict) > 0:
             # Iterate over TICKET_ATTRIBUTES to make a canonical ticket
             candict = {}
             for f in BibCatalogSystem.TICKET_ATTRIBUTES: