Support XMPIP-0015

counterpartylib/lib/messages/trigger.py

@@ -18,9 +18,41 @@
 LENGTH = 32
 ID = 120
 
-receivers = [
-    asset_metadata.asset_metadata_receiver,
-]
+_INITIALISER_RECEIVERS = []
+_PARSER_RECEIVERS = {}
+
+class NoTargetTableNameError(Exception):
+    pass
+class DuplicateTargetTableNameError(Exception):
+    pass
+
+def trigger_initiailser():
+    def wrapper(func):
+        global _INITIALISER_RECEIVERS
+        _INITIALISER_RECEIVERS += func
+        return func
+    return wrapper
+
+def trigger_parser(trigger_id = 0, target_table_name = None):
+    def wrapper(func):
+        global _PARSER_RECEIVERS
+
+        def _wrapper(*args, **kwargs):
+            return func(*args, **kwargs)
+
+        if target_table_name is None:
+            raise NoTargetTableNameError
+        if 'target_table_name' in _PARSER_RECEIVERS:
+            raise DuplicateTargetTableNameError
+        _PARSER_RECEIVERS += {
+            trigger_id: {
+                'target_table_name': target_table_name,
+                'func': func
+            }
+        }
+        return _wrapper
+    return wrapper
+
 
 def initialise (db):
     cursor = db.cursor()
@@ -42,37 +74,26 @@ def initialise (db):
                       source_idx ON triggers (source)
                    ''')
 
-    for receiver in receivers:
-        receiver.initialise(db)
+    for init in _INITIALISER_RECEIVERS:
+        init()
 
 def validate (db, source, target_hash, payload_bytes):
     problems = []
-    targets = []
-    target_type = None
+    target_table_name = None
 
     cursor = db.cursor()
-    receiver_instance = None
-    for receiver in receivers:
-        sql = 'SELECT tx_hash FROM ' + receiver.target_table_name() + ' WHERE tx_hash = ?'
-        cursor.execute(sql, (target_hash,))
+    for receiver in _PARSER_RECEIVERS:
+        sql = 'SELECT tx_hash FROM ' + receiver.target_table_name + ' WHERE tx_hash = ? AND status = ?'
+        cursor.execute(sql, (target_hash,'valid'))
         targets = cursor.fetchall()
-        if targets:
-            assert receiver_instance is None
-            assert len(targets) == 1
-            receiver_instance = receiver(db, source, target_hash, payload_bytes)
-            problems += receiver_instance.validate()
-
-    if receiver_instance is None:
-        problems.append('no trigger target with that hash')
+        assert len(targets) <= 1
+        if len(targets) == 1:
+            target_table_name = receiver.target_table_name
 
-    fee = int(0.001 * config.UNIT)
-    cursor.execute('''SELECT * FROM balances
-                      WHERE (address = ? AND asset = ?)''', (source, config.XCP))
-    balances = cursor.fetchall()
-    if not balances or balances[0]['quantity'] < fee:
-        problems.append('insufficient funds')
+    if target_table_name is None:
+        problems.append('no valid trigger target')
 
-    return receiver_instance, fee, problems
+    return target_table_name, problems
 
 def compose (db, source, target_hash, payload, payload_is_hex):
     # convert memo to memo_bytes based on memo_is_hex setting
@@ -85,12 +106,14 @@ def compose (db, source, target_hash, payload, payload_is_hex):
             raise exceptions.ComposeError(['failed to convert the payload'])
 
     else:
-        payload_bytes = struct.pack(">{}s".format(len(payload)),
+        payload_bytes = struct.pack(
+            ">{}s".format(len(payload)),
             payload.encode('utf-8'))
 
     # Check that target exists.
-    _, _, problems = validate(db, source, target_hash, payload_bytes)
-    if problems: raise exceptions.ComposeError(problems)
+    _, problems = validate(db, source, target_hash, payload_bytes)
+    if problems:
+        raise exceptions.ComposeError(problems)
 
     target_hash_bytes = binascii.unhexlify(bytes(target_hash, 'utf-8'))
 
@@ -122,17 +145,16 @@ def parse (db, tx, message):
         status = 'invalid: could not unpack'
 
     if status == 'valid':
-        receiver, fee, problems = validate(db, tx['source'], target_hash, payload_bytes)
-        if problems:
-            status = 'invalid: ' + '; '.join(problems)
+        target_table_name, problems = validate(db, tx['source'], target_hash, payload_bytes)
 
     if status == 'valid':
         try:
-            problems += receiver.execute(tx)
-            if problems:
-                status = 'invalid: ' + '; '.join(problems)
+            problems += _PARSER_RECEIVERS[target_table_name](db, tx, payload_bytes)
         except:
-            status = 'invalid: execution failed'
+            problems += [ 'invalid: trigger execution failed' ]
+
+    if status == 'valid' and problems:
+        status = 'invalid: ' + '; '.join(problems)
 
     # Add parsed transaction to message-type–specific table.
     bindings = {
@@ -144,14 +166,14 @@ def parse (db, tx, message):
         'payload': payload_bytes,
         'status': status,
     }
-    if "integer overflow" not in status:
-        sql='INSERT INTO triggers VALUES (:tx_index, :tx_hash, :block_index, :source, :target_hash, :payload, :status)'
-        cursor.execute(sql, bindings)
-    else:
-        logger.warn("Not storing [trigger] tx [%s]: %s", tx['tx_hash'], status)
-        logger.debug("Bindings: %s", json.dumps(bindings))
-
-    if status == 'valid':
-        util.debit(db, tx['source'], config.XCP, fee, action="trigger fee", event=tx['tx_hash'])
+    sql = '''INSERT INTO triggers VALUES (
+        :tx_index,
+        :tx_hash,
+        :block_index,
+        :source,
+        :target_hash,
+        :payload,
+        :status)'''
+    cursor.execute(sql, bindings)
 
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