added begining of failure backend

Author: Matt George

src/pyres/failure/__init__.py

@@ -0,0 +1,11 @@
+import datetime
+from pyres import ResQ 
+import sys, traceback
+from pyres.failure.redis import RedisBackend
+_backend = RedisBackend
+def create(options={}):
+    return _backend(*options).save()
+
+
+    
+    

src/pyres/failure/base.py

@@ -0,0 +1,27 @@
+class BaseBackend(object):
+    def __init__(self, exp, queue, payload):
+        excc, _, tb = sys.exc_info()
+        
+        self._exception = excc
+        self._traceback = tb
+        #self._worker = worker
+        self._queue = queue
+        self._payload = payload
+    
+    
+    def _parse_traceback(self, trace):
+        """Return the given traceback string formatted for a notification."""
+        p_traceback = [ "%s:%d:in `%s'" % (filename, lineno, funcname) 
+                        for filename, lineno, funcname, _
+                        in traceback.extract_tb(trace) ]
+        p_traceback.reverse()
+
+        return p_traceback
+    
+    def _parse_message(self, exc):
+        """Return a message for a notification from the given exception."""
+        return '%s: %s' % (exc.__class__.__name__, str(exc))
+    
+    @classmethod
+    def count(cls, resq):
+        return int(resq.redis.llen('failed'))

src/pyres/failure/redis.py

@@ -0,0 +1,14 @@
+from base import BaseBackend
+class RedisBackend(BaseBackend):
+    def save(self, resq=None):
+        if not resq:
+            resq = ResQ()
+        data = {
+            'failed_at' : str(datetime.datetime.now()),
+            'payload'   : self._payload,
+            'error'     : self._parse_message(self._exception),
+            'backtrace' : self._parse_traceback(self._traceback),
+            'queue'     : self._queue
+        }
+        data = ResQ.encode(data)
+        resq.redis.push('failed', data)