Make the rebaseline log server resilient to large logs.

Tools/RebaselineLogServer/main.py

 # Copyright (C) 2013 Google Inc. All rights reserved.
 #
 # Redistribution and use in source and binary forms, with or without
 # modification, are permitted provided that the following conditions are
 # met:
 #
 #     * Redistributions of source code must retain the above copyright
 # notice, this list of conditions and the following disclaimer.
 #     * Redistributions in binary form must reproduce the above
 # copyright notice, this list of conditions and the following disclaimer
@@ skipping 14 matching lines @@
 # THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 # (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 # OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
 import datetime
 import logging
 import webapp2
 
 from google.appengine.ext import ndb
 from google.appengine.ext.webapp import template
+from google.appengine.ext.db import BadRequestError
 
 # A simple log server for rebaseline-o-matic.
 #
 # Accepts updates to the same log entry and shows a simple status page.
 # Has a special state for the case where there are no NeedsRebaseline
 # lines in TestExpectations to avoid cluttering the log with useless
 # entries every 30 seconds.
 #
 # Other than that, new updatelog calls append to the most recent log
 # entry until they have the newentry parameter, in which case, it
@@ skipping 48 matching lines @@
                 elif log_entry.is_no_needs_rebaseline:
                     out = "Previous entry was a no need rebaseline log. Writing a new log."
                     new_entry = True
                 else:
                     out = "Added to existing log entry."
                     log_entry.content = log_entry.content + "\n" + new_log_data
 
         if new_entry or not log_entries:
             log_entry = LogEntry(content=new_log_data, is_no_needs_rebaseline=no_needs_rebaseline)
 
-        log_entry.put()
+        try:
+            log_entry.put()
+        except BadRequestError:
+            out = "Created new log entry because the previous one exceeded the max length."
+            LogEntry(content=new_log_data, is_no_needs_rebaseline=no_needs_rebaseline).put()
+
         self.response.out.write(out)
 
 
 class UploadForm(webapp2.RequestHandler):
     def get(self):
         self.response.out.write(template.render("uploadform.html", {
             "update_log_url": "/updatelog",
             "set_no_needs_rebaseline_url": "/noneedsrebaselines",
             "log_param": LOG_PARAM,
             "new_entry_param": NEW_ENTRY_PARAM,
@@ skipping 20 matching lines @@
         }))
 
 
 routes = [
     ('/uploadform', UploadForm),
     ('/updatelog', UpdateLog),
     ('/', ShowLatest),
 ]
 
 app = webapp2.WSGIApplication(routes, debug=True)