handle graph database not initially existing gracefully

diff --git a/p2pool/util/graph.py b/p2pool/util/graph.py
index a7a3c68..47bf7bb 100644 (file)
--- a/p2pool/util/graph.py
+++ b/p2pool/util/graph.py
@@ -1,16 +1,7 @@
 from __future__ import absolute_import
 from __future__ import division
 
-import json
 import math
-import os
-
-from twisted.python import log
-
-
-def _atomic_write(filename, data):
-    open(filename + '.new', 'w').write(data)
-    os.rename(filename + '.new', filename)
 
 
 class DataViewDescription(object):
@@ -61,25 +52,10 @@ class DataStream(object):
 
 class HistoryDatabase(object):
     @classmethod
-    def from_nothing(cls, datastream_descriptions):
-        return cls(dict(
-            (ds_name, DataStream(ds_desc, dict(
-                (dv_name, DataView(dv_desc, ds_desc, 0, dv_desc.bin_count*[(0, 0)]))
-                for dv_name, dv_desc in ds_desc.dataview_descriptions.iteritems()
-            )))
-            for ds_name, ds_desc in datastream_descriptions.iteritems()
-        ))
-    
-    @classmethod
-    def from_file(cls, datastream_descriptions, filename):
-        try:
-            data = json.loads(open(filename, 'rb').read())
-        except Exception: # XXX
-            log.err()
-            data = {}
+    def from_obj(cls, datastream_descriptions, obj={}):
         def get_dataview(ds_name, ds_desc, dv_name, dv_desc):
-            if ds_name in data:
-                ds_data = data[ds_name]
+            if ds_name in obj:
+                ds_data = obj[ds_name]
                 if dv_name in ds_data:
                     dv_data = ds_data[dv_name]
                     if dv_data['bin_width'] == dv_desc.bin_width and len(dv_data['bins']) == dv_desc.bin_count:
@@ -96,8 +72,6 @@ class HistoryDatabase(object):
     def __init__(self, datastreams):
         self.datastreams = datastreams
     
-    def write(self, filename):
-        _atomic_write(filename, json.dumps(
-            dict((ds_name, dict((dv_name, dict(last_bin_end=dv.last_bin_end, bin_width=dv.desc.bin_width, bins=dv.bins))
-                for dv_name, dv in ds.dataviews.iteritems())) for ds_name, ds in self.datastreams.iteritems())
-        ))
+    def to_obj(self):
+        return dict((ds_name, dict((dv_name, dict(last_bin_end=dv.last_bin_end, bin_width=dv.desc.bin_width, bins=dv.bins))
+            for dv_name, dv in ds.dataviews.iteritems())) for ds_name, ds in self.datastreams.iteritems())

diff --git a/p2pool/web.py b/p2pool/web.py
index 8208d20..d08b186 100644 (file)
--- a/p2pool/web.py
+++ b/p2pool/web.py
@@ -335,17 +335,27 @@ def get_web_root(tracker, current_work, current_work2, get_current_txouts, datad
         if user is not None:
             reactor.callLater(1, grapher.add_localminer_point, user, work, dead)
     
+    hd_path = os.path.join(datadir_path, 'graph_db')
+    hd_obj = {}
+    if os.path.exists(hd_path):
+        try:
+            hd_obj = json.loads(open(hd_path, 'rb').read())
+        except Exception:
+            log.err(None, 'Error reading graph database:')
     dataview_descriptions = {
         'last_hour': graph.DataViewDescription(150, 60*60),
         'last_day': graph.DataViewDescription(300, 60*60*24),
         'last_week': graph.DataViewDescription(300, 60*60*24*7),
         'last_month': graph.DataViewDescription(300, 60*60*24*30),
     }
-    hd = graph.HistoryDatabase.from_file({
+    hd = graph.HistoryDatabase.from_obj({
         'local_hash_rate': graph.DataStreamDescription(False, dataview_descriptions),
         'local_dead_hash_rate': graph.DataStreamDescription(False, dataview_descriptions),
-    }, os.path.join(datadir_path, 'graph_db'))
-    task.LoopingCall(hd.write, os.path.join(datadir_path, 'graph_db')).start(100)
+    }, hd_obj)
+    def _atomic_write(filename, data):
+        open(filename + '.new', 'w').write(data)
+        os.rename(filename + '.new', filename)
+    task.LoopingCall(lambda: _atomic_write(hd_path, json.dumps(hd.to_obj()))).start(100)
     @pseudoshare_received.watch
     def _(work, dead, user):
         t = time.time()