Fix reorg service

safe_transaction_service/history/models.py

@@ -111,10 +111,10 @@ def create_from_block(self, block: Dict[str, Any], current_block_number: Optiona
 
 
 class EthereumBlockQuerySet(models.QuerySet):
-    def not_confirmed(self, current_block_number: Optional[int] = None):
+    def not_confirmed(self, to_block_number: Optional[int] = None):
         queryset = self.filter(confirmed=False)
-        if current_block_number is not None:
-            queryset = queryset.filter(number__lte=current_block_number - 6)
+        if to_block_number is not None:
+            queryset = queryset.filter(number__lte=to_block_number)
         return queryset.order_by('number')
 
 
@@ -126,16 +126,16 @@ class EthereumBlock(models.Model):
     timestamp = models.DateTimeField()
     block_hash = Sha3HashField(unique=True)
     parent_hash = Sha3HashField(unique=True)
+    # For reorgs, True if `current_block_number` - `number` >= MIN_CONFIRMATIONS
     confirmed = models.BooleanField(default=False,
-                                    db_index=True)  # For reorgs, True if `current_block_number` - `number` >= 6
+                                    db_index=True)
 
     def __str__(self):
         return f'Block number={self.number} on {self.timestamp}'
 
-    def set_confirmed(self, current_block_number: int):
-        if (current_block_number - self.number) >= 6:
-            self.confirmed = True
-            self.save()
+    def set_confirmed(self):
+        self.confirmed = True
+        self.save()
 
 
 class EthereumTxManager(models.Manager):

safe_transaction_service/history/services/reorg_service.py

@@ -1,7 +1,7 @@
 import logging
 from typing import Dict, List, NoReturn, Optional
 
-from django.db import models
+from django.db import models, transaction
 
 from hexbytes import HexBytes
 
@@ -27,6 +27,8 @@ def del_singleton(cls):
 
 # TODO Test ReorgService
 class ReorgService:
+    SAFE_CONFIRMATIONS = 6
+
     def __init__(self, ethereum_client: EthereumClient):
         self.ethereum_client = ethereum_client
         # Dictionary with Django model and attribute for reorgs
@@ -41,14 +43,16 @@ def check_reorgs(self) -> Optional[int]:
         :return: Number of oldest block with reorg detected. `None` if not reorg found
         """
         current_block_number = self.ethereum_client.current_block_number
-        for database_block in EthereumBlock.objects.not_confirmed(current_block_number=current_block_number):
+        to_block = current_block_number - self.SAFE_CONFIRMATIONS
+        for database_block in EthereumBlock.objects.not_confirmed(current_block_number=to_block):
             blockchain_block = self.ethereum_client.get_block(database_block.number, full_transactions=False)
             if HexBytes(blockchain_block['hash']) == HexBytes(database_block.block_hash):
-                database_block.set_confirmed(current_block_number)
+                database_block.set_confirmed()
             else:
                 logger.warning('Reorg found for block-number=%d', database_block.number)
                 return database_block.number
 
+    @transaction.atomic
     def recover_from_reorg(self, first_reorg_block_number: int) -> int:
         """
         :param first_reorg_block_number:

safe_transaction_service/history/tasks.py

@@ -1,4 +1,5 @@
 import signal
+import time
 from typing import Any, Dict, NoReturn, Optional, Type, Union
 
 from django.conf import settings
@@ -169,6 +170,7 @@ def check_reorgs_task() -> Optional[int]:
                                            for task_id in redis.lrange(blockchain_running_tasks_key, 0, -1)],
                                           terminate=True, signal=signal.SIGTERM)
                 redis.delete(blockchain_running_tasks_key)
+                time.sleep(5)
                 reorg_service.recover_from_reorg(first_reorg_block_number)
                 return first_reorg_block_number
     except LockError: