feat(utils): Implement VFSHelper for in-memory artifact management

backend/src/ea_chatbot/utils/vfs.py

@@ -0,0 +1,33 @@
+from typing import Dict, Any, Optional, Tuple, List
+
+class VFSHelper:
+    """Helper class for managing in-memory Virtual File System (VFS) artifacts."""
+    
+    def __init__(self, vfs_state: Dict[str, Any]):
+        """Initialize with a reference to the VFS state from AgentState."""
+        self._vfs = vfs_state
+        
+    def write(self, filename: str, content: Any, metadata: Optional[Dict[str, Any]] = None) -> None:
+        """Write a file to the VFS."""
+        self._vfs[filename] = {
+            "content": content,
+            "metadata": metadata or {}
+        }
+        
+    def read(self, filename: str) -> Tuple[Optional[Any], Optional[Dict[str, Any]]]:
+        """Read a file and its metadata from the VFS. Returns (None, None) if not found."""
+        file_data = self._vfs.get(filename)
+        if file_data:
+            return file_data["content"], file_data["metadata"]
+        return None, None
+        
+    def list(self) -> List[str]:
+        """List all filenames in the VFS."""
+        return list(self._vfs.keys())
+        
+    def delete(self, filename: str) -> bool:
+        """Delete a file from the VFS. Returns True if deleted, False if not found."""
+        if filename in self._vfs:
+            del self._vfs[filename]
+            return True
+        return False

backend/tests/test_vfs.py

@@ -0,0 +1,49 @@
+import pytest
+from ea_chatbot.utils.vfs import VFSHelper
+
+def test_vfs_read_write():
+    """Verify that we can write and read from the VFS."""
+    vfs = {}
+    helper = VFSHelper(vfs)
+    
+    helper.write("test.txt", "Hello World", metadata={"type": "text"})
+    assert "test.txt" in vfs
+    assert vfs["test.txt"]["content"] == "Hello World"
+    assert vfs["test.txt"]["metadata"]["type"] == "text"
+    
+    content, metadata = helper.read("test.txt")
+    assert content == "Hello World"
+    assert metadata["type"] == "text"
+
+def test_vfs_list():
+    """Verify that we can list files in the VFS."""
+    vfs = {}
+    helper = VFSHelper(vfs)
+    
+    helper.write("a.txt", "content a")
+    helper.write("b.txt", "content b")
+    
+    files = helper.list()
+    assert "a.txt" in files
+    assert "b.txt" in files
+    assert len(files) == 2
+
+def test_vfs_delete():
+    """Verify that we can delete files from the VFS."""
+    vfs = {}
+    helper = VFSHelper(vfs)
+    
+    helper.write("test.txt", "Hello")
+    helper.delete("test.txt")
+    
+    assert "test.txt" not in vfs
+    assert len(helper.list()) == 0
+
+def test_vfs_not_found():
+    """Verify that reading a non-existent file returns None."""
+    vfs = {}
+    helper = VFSHelper(vfs)
+    
+    content, metadata = helper.read("missing.txt")
+    assert content is None
+    assert metadata is None