Recreate adapter only per block

CHANGELOG

@@ -1,3 +1,5 @@
+- 0.2.9
+	* Minimize instantiations of adapters in filter execution
 - 0.2.8
 	* Upgrade chainsyncer
 - 0.2.7

chaind/filter.py

@@ -26,43 +26,69 @@ class StateFilter(SyncFilter):
         self.adapter_path = adapter_path
         self.tx_adapter = tx_adapter
         self.throttler = throttler
+        self.last_block_height = 0
+        self.adapter = None
+        self.store_lock = None
+
+
+    def __get_adapter(self, block, force_reload=False):
+        if self.store_lock == None:
+            self.store_lock = StoreLock()
+
+        reload = False
+        if block.number != self.last_block_height:
+            reload = True
+        elif self.adapter == None:
+            reload = True
+        elif force_reload:
+            reload = True
+        
+        self.last_block_height = block.number
+
+        if reload:
+            while True:
+                logg.info('reloading adapter')
+                try:
+                    self.adapter = ChaindFsAdapter(
+                        self.chain_spec,
+                        self.adapter_path,
+                        self.tx_adapter,
+                        None,
+                        )
+                    break
+                except BackendError as e:
+                    logg.error('adapter instantiation failed: {}, one more try'.format(e))
+                    self.store_lock.again()
+                    continue
+
+        return self.adapter
 
 
     def filter(self, conn, block, tx, session=None):
         cache_tx = None
-        store_lock = StoreLock()
-        queue_adapter = None
+        queue_adapter = self.__get_adapter(block)
+        
+        self.store_lock.reset()
+    
         while True:
-            try:
-                queue_adapter = ChaindFsAdapter(
-                    self.chain_spec,
-                    self.adapter_path,
-                    self.tx_adapter,
-                    None,
-                    )
-            except BackendError as e:
-                logg.error('adapter instantiation failed: {}, one more try'.format(e))
-                store_lock.again()
-                continue
-
-            store_lock.reset()
-
             try:
                 cache_tx = queue_adapter.get(tx.hash)
                 break
             except NotLocalTxError:
                 logg.debug('skipping not local transaction {}'.format(tx.hash))
+                self.__stop_adapter()
                 return False
             except BackendError as e:
                 logg.error('adapter get failed: {}, one more try'.format(e))
-                queue_adapter = None
-                store_lock.again()
+                self.store_lock.again()
+                queue_adapter = self.__get_adapter(block, force_reload=True)
                 continue
 
         if cache_tx == None:
             raise NotLocalTxError(tx.hash)
 
-        store_lock = StoreLock()
+        self.store_lock.reset()
+
         queue_lock = StoreLock(error=QueueLockError)
         while True:
             try:
@@ -76,15 +102,18 @@ class StateFilter(SyncFilter):
                 queue_lock.again()
             except FileNotFoundError as e:
                 logg.debug('queue item {} not found, possible race condition, will retry: {}'.format(tx.hash, e))
-                store_lock.again()
+                self.store_lock.again()
+                queue_adapter = self.__get_adapter(block, force_reload=True)
                 continue
             except NotLocalTxError as e:
                 logg.debug('queue item {} not found, possible race condition, will retry: {}'.format(tx.hash, e))
-                store_lock.again()
+                self.store_lock.again()
+                queue_adapter = self.__get_adapter(block, force_reload=True)
                 continue
             except StateLockedKey as e:
                 logg.debug('queue item {} not found, possible race condition, will retry: {}'.format(tx.hash, e))
-                store_lock.again()
+                self.store_lock.again()
+                queue_adapter = self.__get_adapter(block, force_reload=True)
                 continue
 
         logg.info('filter registered {} for {} in {}'.format(tx.status.name, tx.hash, block))

setup.cfg

@@ -1,6 +1,6 @@
 [metadata]
 name = chaind
-version = 0.2.8
+version = 0.2.9
 description = Base package for chain queue service
 author = Louis Holbrook
 author_email = dev@holbrook.no