feat: Add custom exceptions

docs_src/src/pages/documentation/api_reference/exceptions.mdx

@@ -1,3 +1,48 @@
+## Handling Errors
+
+Batman learned how to handle the error for different exception in his application. He wrote the following code to handle exceptions :
+
+<Row>
+<Col>
+</Col>
+  <Col sticky>
+
+    <CodeGroup title="Request" tag="GET" label="/hello_world/{item_id}">
+
+    ```python {{ title: 'untyped' }}
+    from robyn import Robyn, HTTPException, status_codes
+
+    app = Robyn(__file__)
+
+    items = {"foo": "The Foo Wrestlers"}
+
+    @app.get("/hello_world/{item_id}")
+    async def read_item(request, item_id):
+        if item_id not in items:
+            raise HTTPException(status_code=status_codes.HTTP_404_NOT_FOUND, detail="Item not found")
+        return {"item": items[item_id]}
+    ```
+
+    ```python {{ title: 'typed' }}
+    from robyn import Robyn, HTTPException, Request, status_codes
+    from typing import Dict
+
+    app = Robyn(__file__)
+
+    items: Dict[str, str] = {"foo": "The Foo Wrestlers"}
+
+
+    @app.get("/hello_world/{item_id}")
+    async def read_item(request: Request, item_id: str) -> Dict[str, str]:
+        if item_id not in items:
+            raise HTTPException(status_code=status_codes.HTTP_404_NOT_FOUND, detail="Item not found")
+        return {"item": items[item_id]}
+
+    ```
+    </CodeGroup>
+  </Col>
+</Row>
+
 ## Custom Exception Handler
 
 Batman learned how to create custom error handlers for different exception types in his application. He wrote the following code to handle exceptions and return a custom error response:

robyn/__init__.py

@@ -28,6 +28,7 @@
 from robyn.router import MiddlewareRouter, MiddlewareType, Router, WebSocketRouter
 from robyn.types import Directory
 from robyn import status_codes
+from robyn.exceptions import HTTPException, WebSocketException
 from robyn.ws import WebSocket
 from robyn.jsonify import jsonify
 
@@ -472,6 +473,8 @@ def ALLOW_CORS(app: Robyn, origins: List[str]):
     "SubRouter",
     "AuthenticationHandler",
     "Headers",
+    "HTTPException",
+    "WebSocketException",
     "WebSocketConnector",
     "WebSocket",
 ]

robyn/exceptions.py

@@ -0,0 +1,29 @@
+import http
+
+
+class HTTPException(Exception):
+    def __init__(self, status_code: int, detail: str | None = None) -> None:
+        if detail is None:
+            detail = http.HTTPStatus(status_code).phrase
+        self.status_code = status_code
+        self.detail = detail
+
+    def __str__(self) -> str:
+        return f"{self.status_code}: {self.detail}"
+
+    def __repr__(self) -> str:
+        class_name = self.__class__.__name__
+        return f"{class_name}(status_code={self.status_code!r}, detail={self.detail!r})"
+
+
+class WebSocketException(Exception):
+    def __init__(self, code: int, reason: str | None = None) -> None:
+        self.code = code
+        self.reason = reason or ""
+
+    def __str__(self) -> str:
+        return f"{self.code}: {self.reason}"
+
+    def __repr__(self) -> str:
+        class_name = self.__class__.__name__
+        return f"{class_name}(code={self.code!r}, reason={self.reason!r})"