start implementation on new architecture

sia/read_entry.py

@@ -0,0 +1,54 @@
+from datetime import datetime
+import xml.etree.ElementTree as ET
+
+from .entry import Entry
+from .util import escape_text_for_xml
+
+class ReadEntry(Entry):
+    """
+    Entry type for reading content from standard input.
+    
+    Attributes:
+        content: Content read from stdin, empty until first update
+        io_buffer: Buffer to use for IO operations
+        _read: Whether content has been read
+    """
+    
+    def __init__(self, io_buffer, id: str, timestamp: datetime):
+        """
+        Initialize a new read entry.
+        
+        Args:
+            io_buffer: Buffer to use for IO operations
+            id: Unique identifier for this entry
+            timestamp: Creation timestamp for this entry
+        """
+        super().__init__(id, timestamp)
+        self.content = ""
+        self.io_buffer = io_buffer
+        self._read = False
+        
+    def update(self) -> None:
+        """
+        Read from stdin if not already read.
+        Uses the provided IO buffer for the actual read operation.
+        """
+        if not self._read:
+            self.content = self.io_buffer.read()
+            self._read = True
+
+    def generate_context(self) -> ET.Element:
+        """
+        Generate an XML Element representing this read entry.
+        
+        Returns:
+            ET.Element: XML element containing the entry's data
+        """
+        # Create root element
+        element = ET.Element("read_stdin", {"id": self.id})
+        
+        # Add content as CDATA or escaped text if content has been read
+        if self._read:
+            element.text = escape_text_for_xml(self.content)
+            
+        return element