logging: Improve the quality of tracebacks from ErrorController.

r2/r2/controllers/error.py

@@ -38,7 +38,7 @@ try:
     from r2.controllers.reddit_base import RedditController, Cookies
     from r2.lib.errors import ErrorSet
     from r2.lib.filters import websafe_json
-    from r2.lib import pages
+    from r2.lib import log, pages
     from r2.lib.strings import rand_strings
     from r2.lib.template_helpers import static
     from r2.models.link import Link
@@ -101,20 +101,20 @@ class ErrorController(RedditController):
         except (HTTPMovedPermanently, HTTPFound):
             # ignore an attempt to redirect from an error page
             pass
-        except:
-            handle_awful_failure("Error occurred in ErrorController.__before__")
+        except Exception as e:
+            handle_awful_failure("ErrorController.__before__: %r" % e)
 
     def __after__(self): 
         try:
             RedditController.__after__(self)
-        except:
-            handle_awful_failure("Error occurred in ErrorController.__after__")
+        except Exception as e:
+            handle_awful_failure("ErrorController.__after__: %r" % e)
 
     def __call__(self, environ, start_response):
         try:
             return RedditController.__call__(self, environ, start_response)
-        except:
-            return handle_awful_failure("something really awful just happened.")
+        except Exception as e:
+            return handle_awful_failure("ErrorController.__call__: %r" % e)
 
 
     def send403(self):
@@ -202,8 +202,8 @@ class ErrorController(RedditController):
                 return self.send404()
             else:
                 return "page not found"
-        except:
-            return handle_awful_failure("something really bad just happened.")
+        except Exception as e:
+            return handle_awful_failure("ErrorController.GET_document: %r" % e)
 
     POST_document = GET_document
 
@@ -220,8 +220,9 @@ def handle_awful_failure(fail_text):
     try:
         # log the traceback, and flag the "path" as the error location
         import traceback
-        g.log.error("FULLPATH: %s" % fail_text)
-        g.log.error(traceback.format_exc())
+        log.write_error_summary(fail_text)
+        for line in traceback.format_exc().splitlines():
+            g.log.error(line)
         return redditbroke % (make_failien_url(), fail_text)
     except:
         # we are doomed.  Admit defeat

r2/r2/lib/log.py

@@ -118,6 +118,13 @@ class LogQueueErrorReporter(Reporter):
         amqp.add_item(QUEUE_NAME, cPickle.dumps(d))
 
 
+def write_error_summary(error):
+    """Log a single-line summary of the error for easy log grepping."""
+    fullpath = request.environ.get('FULLPATH', request.path)
+    uid = c.user._id if c.user_is_loggedin else '-'
+    g.log.error("E: %s U: %s FP: %s", error, uid, fullpath)
+
+
 class LoggingErrorReporter(Reporter):
     """ErrorMiddleware-compatible reporter that writes exceptions to g.log."""
 
@@ -125,15 +132,9 @@ class LoggingErrorReporter(Reporter):
         # exception_formatted is the output of traceback.format_exception_only
         exception = exc_data.exception_formatted[-1].strip()
 
-        # This is still within the RegistryManager middleware
-        fullpath = request.environ.get('FULLPATH', request.path)
-        uid = '-'
-        if c.user_is_loggedin:
-            uid = c.user._id
-
         # First emit a single-line summary.  This is great for grepping the
         # streaming log for errors.
-        g.log.error("E: %s U: %s FP: %s", exception, uid, fullpath)
+        write_error_summary(exception)
 
         text, extra = self.format_text(exc_data)
         # TODO: send this all in one burst so that error reports aren't