Solve format issue on balance pre-check (#855)

* Fix: Solve issue on format getting IPFS file sizes before downloading the entire content.

* Fix: Added test cae for string dag_node format

Author: nesitor

src/aleph/services/ipfs/service.py

@@ -68,6 +68,9 @@ async def get_ipfs_size(
                 dag_node = await asyncio.wait_for(
                     self.ipfs_client.dag.get(hash), timeout=timeout
                 )
+                result = 0
+                if isinstance(dag_node, str):
+                    dag_node = json.loads(dag_node)
                 if isinstance(dag_node, dict):
                     if "Data" in dag_node and isinstance(dag_node["Data"], dict):
                         # This is the common structure for UnixFS nodes after aioipfs parsing
@@ -81,7 +84,11 @@ async def get_ipfs_size(
                             "Tsize" in dag_node
                         ):  # Sometimes it might be at the top level directly
                             result = dag_node["Tsize"]
-                    elif "Links" in dag_node and isinstance(dag_node["Links"], list):
+                    if (
+                        result == 0
+                        and "Links" in dag_node
+                        and isinstance(dag_node["Links"], list)
+                    ):
                         total_size = 0
                         for link in dag_node["Links"]:
                             # In case it's a link list, get the Tsize property if exists

tests/services/test_ipfs_service.py

@@ -1,4 +1,5 @@
 import asyncio
+import json
 from unittest.mock import AsyncMock, patch
 
 import aioipfs
@@ -133,6 +134,31 @@ async def test_get_ipfs_size_non_dict():
     ipfs_client.block.stat.assert_called_once_with("test_hash")
 
 
+@pytest.mark.asyncio
+async def test_get_ipfs_size_json():
+    """Test when dag.get returns a non-dictionary (bytes)"""
+    # Setup
+    mock_dag_get_data = {
+        "Data": {"/": {"bytes": "CAE"}},
+        "Links": [
+            {"Hash": {"/": "hash1"}, "Name": "test1", "Tsize": 12596071},
+            {"Hash": {"/": "hash2"}, "Name": "test2", "Tsize": 20168090},
+        ],
+    }
+    ipfs_client = AsyncMock()
+    ipfs_client.dag.get = AsyncMock(return_value=json.dumps(mock_dag_get_data))
+
+    service = IpfsService(ipfs_client=ipfs_client)
+
+    # Execute
+    result = await service.get_ipfs_size("test_hash")
+
+    # Assert
+    assert result == 32764161
+    ipfs_client.dag.get.assert_called_once_with("test_hash")
+    ipfs_client.block.stat.assert_not_called()
+
+
 @pytest.mark.asyncio
 async def test_get_ipfs_size_api_error():
     """Test handling of APIError"""