introduce strategy chains

atxm/_task.py

@@ -17,6 +17,7 @@ def __init__(self, interval: float = INTERVAL):
         self.log = Logger(self.__class__.__name__)
         self._task = LoopingCall(self.run)
         self._task.clock = self.CLOCK
+        self._task.interval = self.interval
 
     @property
     def running(self) -> bool:

atxm/exceptions.py

@@ -1,6 +1,31 @@
+from enum import Enum
+
 from web3.types import RPCError
 
 
+class Faults(Enum):
+    """
+    Fault codes for transaction processing.
+    These are alternate states that a transaction can enter
+    other than "finalized".
+    """
+
+    # Strategy has been running for too long
+    TIMEOUT = "timeout"
+
+    # Transaction has been capped and subsequently timed out
+    PAUSE = "pause"
+
+    # Transaction reverted
+    REVERT = "revert"
+
+    # Something went wrong
+    ERROR = "error"
+
+    # ...
+    INSUFFICIENT_FUNDS = "insufficient_funds"
+
+
 class TransactionFinalized(Exception):
     """raised when a transaction has been included in a block"""
 
@@ -9,12 +34,29 @@ class InsufficientFunds(RPCError):
     """raised when a transaction exceeds the spending cap"""
 
 
-class Halt(Exception):
+class Wait(Exception):
     """
     Raised when a strategy exceeds a limitation.
     Used to mark a pending transaction as "wait, don't retry".
     """
 
 
+class Fault(Exception):
+    """raised when a transaction has been faulted"""
+
+    def __init__(
+            self,
+            tx: "AsyncTx",
+            fault: Faults,
+            clear: bool,
+            message: str
+    ):
+        self.tx = tx
+        self.fault = fault
+        self.message = message
+        self.clear = clear
+        super().__init__(message)
+
+
 class TransactionReverted(Exception):
     """raised when a transaction has been reverted"""