Provide error handlers

provider/main/errors.py

@@ -10,11 +10,20 @@
 Functions:
 
     handle_error(e) -> Any
+    bad_request(e) -> Any
+    page_not_found(e) -> Any
+    method_not_allowed(e) -> Any
+    on_json_loading_failed(e: Request, error: json.decoder.JSONDecodeError)
 
 """
 
-from flask import abort, json
-from werkzeug.exceptions import HTTPException
+from flask import json, Request
+from werkzeug.exceptions import (
+    HTTPException,
+    BadRequest,
+    NotFound,
+    MethodNotAllowed
+)
 
 from provider.main import main
 
@@ -31,3 +40,32 @@ def handle_error(e):
     })
     response.content_type = 'application/json'
     return response
+
+
+@main.app_errorhandler(400)
+def bad_request(e):
+    """Registers a function to handle 400 errors."""
+    return handle_error(BadRequest(response=e.get_response()))
+
+
+@main.app_errorhandler(404)
+def page_not_found(e):
+    """Registers a function to handle 404 errors."""
+    return handle_error(NotFound(response=e.get_response()))
+
+
+@main.app_errorhandler(405)
+def method_not_allowed(e):
+    """Registers a function to handle 405 errors."""
+    return handle_error(MethodNotAllowed(response=e.get_response()))
+
+
+def on_json_loading_failed(req, error):
+    """Abort with a custom JSON message."""
+    raise BadRequest(
+        description=f'''Failed to decode JSON object: {error}''',
+        response=req
+    )
+
+
+Request.on_json_loading_failed = on_json_loading_failed