chore: Finalize cleanup phases (docstrings, utility consolidation, dev app isolation)

backend/src/ea_chatbot/api/routers/agent.py

@@ -3,14 +3,12 @@ from typing import AsyncGenerator, List
 from fastapi import APIRouter, Depends, HTTPException
 from fastapi.responses import StreamingResponse
 from ea_chatbot.api.dependencies import get_current_user, history_manager
-from ea_chatbot.api.utils import convert_to_json_compatible
+from ea_chatbot.api.utils import convert_to_json_compatible, map_db_messages_to_langchain
 from ea_chatbot.graph.workflow import app
 from ea_chatbot.graph.checkpoint import get_checkpointer
 from ea_chatbot.history.models import User as UserDB, Conversation
-from ea_chatbot.history.utils import map_db_messages_to_langchain
 from ea_chatbot.api.schemas import ChatRequest
 from ea_chatbot.utils.plots import fig_to_bytes
-import io
 import base64
 from langchain_core.runnables.config import RunnableConfig
 from langchain_core.messages import BaseMessage

backend/src/ea_chatbot/api/utils.py

@@ -1,12 +1,39 @@
 from datetime import datetime, timedelta, timezone
-from typing import Optional, Any
+from typing import Optional, Any, List
 from jose import JWTError, jwt
 from pydantic import BaseModel
-from langchain_core.messages import BaseMessage
+from langchain_core.messages import BaseMessage, HumanMessage, AIMessage, SystemMessage
 from ea_chatbot.config import Settings
+from ea_chatbot.history.models import Message
 
 settings = Settings()
 
+def map_db_messages_to_langchain(db_messages: List[Message]) -> List[BaseMessage] :
+    """
+    Converts a list of database Message models to LangChain BaseMessage objects.
+    
+    Args:
+        db_messages: List of Message objects from the database.
+        
+    Returns:
+        List of HumanMessage, AIMessage, or SystemMessage objects.
+    """
+    lc_messages: List[BaseMessage] = []
+    
+    for m in db_messages:
+        role = m.role.lower()
+        if role == "user":
+            lc_messages.append(HumanMessage(content=m.content))
+        elif role == "assistant":
+            lc_messages.append(AIMessage(content=m.content))
+        elif role == "system":
+            lc_messages.append(SystemMessage(content=m.content))
+        else:
+            # Default to HumanMessage for unknown roles
+            lc_messages.append(HumanMessage(content=m.content))
+            
+    return lc_messages
+
 def create_access_token(data: dict, expires_delta: Optional[timedelta] = None) -> str:
     """
     Create a JWT access token.

backend/src/ea_chatbot/history/utils.py

@@ -1,30 +0,0 @@
-"""Utility functions for history management."""
-from typing import List
-from langchain_core.messages import BaseMessage, HumanMessage, AIMessage, SystemMessage
-from ea_chatbot.history.models import Message
-
-def map_db_messages_to_langchain(db_messages: List[Message]) -> List[BaseMessage] :
-    """
-    Converts a list of database Message models to LangChain BaseMessage objects.
-    
-    Args:
-        db_messages: List of Message objects from the database.
-        
-    Returns:
-        List of HumanMessage, AIMessage, or SystemMessage objects.
-    """
-    lc_messages: List[BaseMessage] = []
-    
-    for m in db_messages:
-        role = m.role.lower()
-        if role == "user":
-            lc_messages.append(HumanMessage(content=m.content))
-        elif role == "assistant":
-            lc_messages.append(AIMessage(content=m.content))
-        elif role == "system":
-            lc_messages.append(SystemMessage(content=m.content))
-        else:
-            # Default to HumanMessage for unknown roles
-            lc_messages.append(HumanMessage(content=m.content))
-            
-    return lc_messages

backend/src/ea_chatbot/utils/plots.py

@@ -3,15 +3,25 @@ import matplotlib.pyplot as plt
 
 def fig_to_bytes(fig: plt.Figure, format: str = "png") -> bytes:
     """
-    Convert a Matplotlib figure to bytes.
+    Convert a Matplotlib figure to a bytes object in the specified format.
+    
+    This utility encapsulates the boilerplate logic for saving a figure to an 
+    in-memory buffer and retrieving its binary content.
 
     Args:
-        fig: The Matplotlib figure to convert.
-        format: The image format to use (default: "png").
+        fig: The Matplotlib Figure object to be converted.
+        format: The image format string (e.g., "png", "jpg", "svg"). 
+            Defaults to "png".
         
     Returns:
-        bytes: The image data.
+        The binary image data as a bytes object.
+
+    Raises:
+        ValueError: If an unsupported image format is provided.
     """
     buf = io.BytesIO()
+    try:
         fig.savefig(buf, format=format)
+    except Exception as e:
+        raise ValueError(f"Failed to convert figure to {format}: {str(e)}") from e
     return buf.getvalue()

backend/tests/test_history_mapping.py

@@ -1,6 +1,6 @@
 import pytest
 from ea_chatbot.history.models import Message
-from ea_chatbot.history.utils import map_db_messages_to_langchain
+from ea_chatbot.api.utils import map_db_messages_to_langchain
 from langchain_core.messages import HumanMessage, AIMessage
 
 def test_map_db_messages_to_langchain():