feat(proxy): implement proxy code validation and error handling

app/api/proxy/router.py

@@ -10,6 +10,7 @@ from db.proxy import (
 )
 from fastapi import APIRouter, Depends, HTTPException, status
 from models.proxy import ProxyCreateInput, ProxyUpdateInput
+from utils.proxy.validator import ProxyCodeValidationError, validate_proxy_code
 
 router = APIRouter(
     prefix="/proxy",
@@ -18,6 +19,16 @@ router = APIRouter(
 )
 
 
+async def _validate_code_or_raise(code: str) -> None:
+    try:
+        await validate_proxy_code(code)
+    except ProxyCodeValidationError as error:
+        raise HTTPException(
+            status_code=status.HTTP_422_UNPROCESSABLE_CONTENT,
+            detail=error.to_http_detail(),
+        ) from error
+
+
 @router.get("")
 async def list_proxies_handler():
     return await list_proxy_documents()
@@ -43,6 +54,8 @@ async def create_proxy_handler(payload: ProxyCreateInput):
             detail=f"Proxy already exists on port {payload.proxy_port}",
         )
 
+    await _validate_code_or_raise(payload.code)
+
     return await create_proxy(
         proxy_port=payload.proxy_port,
         name=payload.name,
@@ -53,6 +66,9 @@ async def create_proxy_handler(payload: ProxyCreateInput):
 
 @router.put("/{proxy_port}")
 async def edit_proxy(proxy_port: int, payload: ProxyUpdateInput):
+    if payload.code is not None:
+        await _validate_code_or_raise(payload.code)
+
     updated_proxy = await update_proxy(proxy_port, payload)
     if updated_proxy is None:
         raise HTTPException(