Merge pull request #47 from drift-labs:goldhaxx/DATA-77/fix-health-page-errors

Refactor cache middleware and enhance health page error handling

Author: goldhaxx

backend/middleware/cache_middleware.py

@@ -392,9 +392,13 @@ async def _fetch_and_cache(
                 logger.warning(
                     f"Failed to fetch data for {request.url.path}. Status code: {response.status_code}"
                 )
-                # Overwrite placeholder with error state or remove? Let's overwrite.
-                with open(cache_file, "w") as f:
-                    json.dump({"content": ERROR_PLACEHOLDER, "status_code": response.status_code, "headers": {}}, f)
+                # On failure, remove the placeholder to allow retries
+                if os.path.exists(cache_file):
+                    try:
+                        os.remove(cache_file)
+                        logger.info(f"Removed placeholder file due to non-200 response: {cache_file}")
+                    except OSError as e:
+                        logger.error(f"Failed to remove placeholder file {cache_file} after non-200 response: {e}")
 
             # Run cleanup AFTER successfully writing new cache or error placeholder
             self.cleanup_old_cache_files()
@@ -403,12 +407,13 @@ async def _fetch_and_cache(
             logger.error(
                 f"Error in background task for {request.url.path} under key {cache_key}: {str(e)}"
             )
-            # Attempt to overwrite placeholder with error state
-            try:
-                with open(cache_file, "w") as f:
-                     json.dump({"content": ERROR_PLACEHOLDER, "status_code": 500, "headers": {}}, f)
-            except Exception as write_e:
-                 logger.error(f"Failed to write error placeholder for {cache_file}: {write_e}")
+            # On failure, remove the placeholder to allow retries
+            if os.path.exists(cache_file):
+                try:
+                    os.remove(cache_file)
+                    logger.info(f"Removed placeholder file due to exception: {cache_file}")
+                except OSError as remove_e:
+                    logger.error(f"Failed to remove placeholder file {cache_file} after exception: {remove_e}")
             import traceback
             traceback.print_exc()
         finally:

src/page/health.py

@@ -12,6 +12,9 @@ def is_processing(result):
     """Checks if the API result indicates backend processing."""
     return isinstance(result, dict) and result.get("result") == "processing"
 
+def has_error(result):
+    """Checks if the API result indicates an error."""
+    return isinstance(result, dict) and "error" in result
 
 def _get_perp_market_symbol_display(market_index):
     """Safely get the display string for a perp market index."""
@@ -190,6 +193,8 @@ def health_page():
 
         if is_processing(largest_perp_positions):
             is_still_processing = True
+        elif has_error(largest_perp_positions):
+            st.error(f"Error fetching largest perp positions: {largest_perp_positions.get('error', 'Unknown error')}")
         else:
             # Convert to DataFrame and add pagination
             df = pd.DataFrame(largest_perp_positions)
@@ -236,6 +241,8 @@ def health_page():
 
         if is_processing(most_levered_positions):
             is_still_processing = True
+        elif has_error(most_levered_positions):
+            st.error(f"Error fetching most levered perp positions: {most_levered_positions.get('error', 'Unknown error')}")
         else:
             # Format market index in most_levered_positions too
             most_levered_df = pd.DataFrame(most_levered_positions)
@@ -310,6 +317,8 @@ def health_page():
 
         if is_processing(largest_spot_borrows):
             is_still_processing = True
+        elif has_error(largest_spot_borrows):
+            st.error(f"Error fetching largest spot borrows: {largest_spot_borrows.get('error', 'Unknown error')}")
         else:
             # Convert to dataframe and add market symbols
             spot_df = pd.DataFrame(largest_spot_borrows)
@@ -356,6 +365,8 @@ def health_page():
         )
         if is_processing(most_levered_borrows):
             is_still_processing = True
+        elif has_error(most_levered_borrows):
+            st.error(f"Error fetching most levered spot borrows: {most_levered_borrows.get('error', 'Unknown error')}")
         else:
             # Convert to dataframe and add market symbols
             levered_spot_df = pd.DataFrame(most_levered_borrows)