Move error handling into separate package.

1 files changed, 62 insertions, 0 deletions

diff --git a/gn_auth/errors/__init__.py b/gn_auth/errors/__init__.py
new file mode 100644
index 0000000..533a842
--- /dev/null
+++ b/gn_auth/errors/__init__.py
@@ -0,0 +1,62 @@
+"""Handle application level errors."""
+import logging
+import traceback
+
+from werkzeug.exceptions import NotFound, HTTPException
+from flask import (Flask,
+                   request,
+                   jsonify,
+                   render_template)
+
+from gn_auth.auth.errors import AuthorisationError
+
+from .tracing import add_trace
+from .http import http_error_handlers
+
+logger = logging.getLogger(__name__)
+
+__all__ = ["register_error_handlers"]
+
+
+def handle_general_exception(exc: Exception):
+    """Handle generic unhandled exceptions."""
+    logger.error("Error occurred!", exc_info=True)
+    content_type = request.content_type
+    if bool(content_type) and content_type.lower() == "application/json":
+        exc_args = [str(x) for x in exc.args]
+        msg = ("The following exception was raised while attempting to access "
+               f"{request.url}: {' '.join(exc_args)}")
+        return jsonify(add_trace(exc, {
+            "error": type(exc).__name__,
+            "error_description": msg
+        })), 500
+
+    return render_template("50x.html",
+                           page=request.url,
+                           error=exc,
+                           trace=traceback.format_exception(exc)), 500
+
+
+def handle_authorisation_error(exc: AuthorisationError):
+    """Handle AuthorisationError if not handled anywhere else."""
+    logger.error("Error occurred!", exc_info=True)
+    logger.error(exc)
+    return jsonify(add_trace(exc, {
+        "error": type(exc).__name__,
+        "error_description": " :: ".join(exc.args)
+    })), exc.error_code
+
+__error_handlers__ = {
+    Exception: handle_general_exception,
+    AuthorisationError: handle_authorisation_error
+}
+
+
+def register_error_handlers(app: Flask):
+    """Register ALL defined error handlers"""
+    _handlers = {
+        **__error_handlers__,
+        **http_error_handlers()
+    }
+    for class_, error_handler in __error_handlers__.items():
+        app.register_error_handler(class_, error_handler)