fix/improve error handling

hyperglass/api/__init__.py

@@ -5,6 +5,7 @@ from pathlib import Path
 
 # Third Party Imports
 from fastapi import FastAPI
+from fastapi.exceptions import RequestValidationError
 from fastapi.openapi.utils import get_openapi
 from starlette.exceptions import HTTPException as StarletteHTTPException
 from starlette.middleware.cors import CORSMiddleware
@@ -13,7 +14,9 @@ from starlette.staticfiles import StaticFiles
 
 # Project Imports
 from hyperglass.api.error_handlers import app_handler
+from hyperglass.api.error_handlers import default_handler
 from hyperglass.api.error_handlers import http_handler
+from hyperglass.api.error_handlers import validation_handler
 from hyperglass.api.events import on_shutdown
 from hyperglass.api.events import on_startup
 from hyperglass.api.routes import docs
@@ -60,6 +63,12 @@ app.add_exception_handler(StarletteHTTPException, http_handler)
 # Backend Application Error Handler
 app.add_exception_handler(HyperglassError, app_handler)
 
+# Validation Error Handler
+app.add_exception_handler(RequestValidationError, validation_handler)
+
+# Uncaught Error Handler
+app.add_exception_handler(Exception, default_handler)
+
 
 def _custom_openapi():
     """Generate custom OpenAPI config."""

hyperglass/api/error_handlers.py

@@ -1,7 +1,18 @@
 """API Error Handlers."""
+
 # Third Party Imports
 from starlette.responses import UJSONResponse
 
+from hyperglass.configuration import params
+
+
+async def default_handler(request, exc):
+    """Handle uncaught errors."""
+    return UJSONResponse(
+        {"output": params.messages.general, "level": "danger", "keywords": []},
+        status_code=500,
+    )
+
 
 async def http_handler(request, exc):
     """Handle web server errors."""
@@ -17,3 +28,12 @@ async def app_handler(request, exc):
         {"output": exc.message, "level": exc.level, "keywords": exc.keywords},
         status_code=exc.status_code,
     )
+
+
+async def validation_handler(request, exc):
+    """Handle Pydantic validation errors raised by FastAPI."""
+    error = exc.errors()[0]
+    return UJSONResponse(
+        {"output": error["msg"], "level": "error", "keywords": error["loc"]},
+        status_code=400,
+    )