feat: token_pause_transaction.py

Author: exploreriii

src/hiero_sdk_python/tokens/token_pause_transaction.py

@@ -0,0 +1,81 @@
+from hiero_sdk_python.tokens.token_id import TokenId
+from hiero_sdk_python.transaction.transaction import Transaction
+from hiero_sdk_python.hapi.services.token_pause_pb2 import TokenPauseTransactionBody
+from hiero_sdk_python.channels import _Channel
+from hiero_sdk_python.executable import _Method
+
+class TokenPauseTransaction(Transaction):
+    """
+    Represents a token pause transaction. 
+    
+    A token pause transaction prevents a token from being involved in any operation.
+
+    The token is required to have a pause key and the pause key must sign.
+    Once a token is paused, token status will update from unpaused to paused. 
+    The token status for tokens that do not have an assigned pause key will state PauseNotApplicable.
+    
+    Inherits from the base Transaction class and implements the required methods
+    to build and execute a token pause transaction.
+    """
+    def __init__(self, token_id=None):
+        """
+        Initializes a new TokenPauseTransaction instance with optional token_id.
+
+        Args:
+            token_id (TokenId, optional): The ID of the token to be paused.
+        """
+        super().__init__()
+        self.token_id : TokenId = token_id
+        
+    def set_token_id(self, token_id):
+        """
+        Sets the ID of the token to be paused.
+
+        Args:
+            token_id (TokenId): The ID of the token to be paused.
+
+        Returns:
+            TokenPauseTransaction: Returns self for method chaining.
+        """
+        self._require_not_frozen()
+        self.token_id = token_id
+        return self
+    
+    def build_transaction_body(self):
+        """
+        Builds and returns the protobuf transaction body for token pause.
+
+        Returns:
+            TransactionBody: The protobuf transaction body containing the token pause details.
+        
+        Raises:
+        ValueError: If no token_id has been set.
+        """
+        if self.token_id is None:
+            raise ValueError("token_id must be set before building the transaction body")
+
+        token_pause_body = TokenPauseTransactionBody(
+            token=self.token_id.to_proto()
+        )
+        transaction_body = self.build_base_transaction_body()
+        transaction_body.tokenPause.CopyFrom(token_pause_body)
+        return transaction_body
+    
+    def _get_method(self, channel: _Channel) -> _Method:
+        return _Method(
+            transaction_func=channel.token.pauseToken,
+            query_func=None
+        )
+    
+    def _from_proto(self, proto: TokenPauseTransactionBody):
+        """
+        Deserializes a TokenPauseTransactionBody from a protobuf object.
+
+        Args:
+            proto (TokenPauseTransactionBody): The protobuf object to deserialize.
+
+        Returns:
+            TokenPauseTransaction: Returns self for method chaining.
+        """
+        self.token_id = TokenId.from_proto(proto.token)
+        return self