[batch] warns the user if client or server is using deprecated functi…

…onality (#14621)

Closes #14485.

Tested that this works by deploying the branch to my dev namespace and
pointing my dev config at it:

```bash
hailctl dev deploy -b iris-garden/hail:batch/deprecated-apis -s deploy_batch,add_developers
hailctl dev config set default_namespace irademac
```

And then running the following:

```python
from hailtop.batch import ServiceBackend
batch_client = await ServiceBackend(billing_project='test', remote_tmpdir='gs://irademac/test/')._batch_client()
# one of the deprecated endpoints
await batch_client._get("/api/v1alpha/batches/402/jobs/1/log")
```

batch/batch/front_end/front_end.py

@@ -219,6 +219,18 @@ def cast_query_param_to_bool(param: Optional[str]) -> bool:
  return True
 
 
+def deprecated(fun):
+ @wraps(fun)
+ async def wrapped(request, *args, **kwargs):
+ response = await fun(request, *args, **kwargs)
+ response.headers["X-Hail-Deprecated"] = (
+ f'The endpoint "{request.url.path}" is deprecated. Please upgrade your Hail version to the latest release.'
+ )
+ return response
+
+ return wrapped
+
+
 @routes.get('/healthcheck')
 async def get_healthcheck(_) -> web.Response:
  return web.Response()
@@ -651,10 +663,10 @@ async def _get_full_job_status(app, record):
  raise
 
 
-# deprecated
 @routes.get('/api/v1alpha/batches/{batch_id}/jobs/{job_id}/log')
 @billing_project_users_only()
 @add_metadata_to_request
+@deprecated
 async def get_job_log(request: web.Request, _, batch_id: int) -> web.Response:
  job_id = int(request.match_info['job_id'])
  job_log_bytes = await _get_job_log(request.app, batch_id, job_id)
@@ -836,10 +848,10 @@ def check_service_account_permissions(user, sa):
  raise web.HTTPBadRequest(reason=f'unauthorized service account {(sa["namespace"], sa["name"])} for user {user}')
 
 
-# Deprecated. Use create_jobs_for_update instead
 @routes.post('/api/v1alpha/batches/{batch_id}/jobs/create')
 @auth.authenticated_users_only()
 @add_metadata_to_request
+@deprecated # Use create_jobs_for_update instead
 async def create_jobs(request: web.Request, userdata: UserData) -> web.Response:
  app = request.app
  batch_id = int(request.match_info['batch_id'])
@@ -2055,10 +2067,10 @@ async def cancel_job_group(request: web.Request, _, batch_id: int) -> web.Respon
  return web.Response()
 
 
-# deprecated
 @routes.patch('/api/v1alpha/batches/{batch_id}/close')
 @auth.authenticated_users_only()
 @add_metadata_to_request
+@deprecated
 async def close_batch(request, userdata):
  batch_id = int(request.match_info['batch_id'])
  user = userdata['username']

gear/gear/http_server_utils.py

@@ -1,3 +1,4 @@
+from collections.abc import Mapping
 from typing import Any, Callable, Optional
 
 import orjson
@@ -8,5 +9,7 @@ async def json_request(request: web.Request) -> Any:
  return orjson.loads(await request.read())
 
 
-def json_response(data: Any, fallback_serializer: Optional[Callable[[Any], Any]] = None) -> web.Response:
- return web.json_response(body=orjson.dumps(data, default=fallback_serializer))
+def json_response(
+ data: Any, fallback_serializer: Optional[Callable[[Any], Any]] = None, headers: Optional[Mapping] = None
+) -> web.Response:
+ return web.json_response(body=orjson.dumps(data, default=fallback_serializer), headers=headers)

hail/python/hailtop/batch_client/aioclient.py

@@ -5,6 +5,7 @@
 import math
 import random
 import secrets
+import warnings
 from enum import Enum
 from typing import Any, AsyncIterator, Dict, List, Optional, Tuple, TypedDict, Union, cast
 
@@ -1303,17 +1304,27 @@ def __init__(self, billing_project: str, url: str, session: Session, headers: Di
  self._session: Session = session
  self._headers = headers
 
+ async def _warn_if_deprecated(self, response: aiohttp.ClientResponse) -> aiohttp.ClientResponse:
+ deprecation_message = response.headers.get("X-Hail-Deprecated")
+ if deprecation_message is not None:
+ warnings.warn(f"DEPRECATED: {deprecation_message}")
+ return response
+
  async def _get(self, path, params=None) -> aiohttp.ClientResponse:
- return await self._session.get(self.url + path, params=params, headers=self._headers)
+ return await self._warn_if_deprecated(
+ await self._session.get(self.url + path, params=params, headers=self._headers)
+ )
 
  async def _post(self, path, data=None, json=None) -> aiohttp.ClientResponse:
- return await self._session.post(self.url + path, data=data, json=json, headers=self._headers)
+ return await self._warn_if_deprecated(
+ await self._session.post(self.url + path, data=data, json=json, headers=self._headers)
+ )
 
  async def _patch(self, path) -> aiohttp.ClientResponse:
- return await self._session.patch(self.url + path, headers=self._headers)
+ return await self._warn_if_deprecated(await self._session.patch(self.url + path, headers=self._headers))
 
  async def _delete(self, path) -> aiohttp.ClientResponse:
- return await self._session.delete(self.url + path, headers=self._headers)
+ return await self._warn_if_deprecated(await self._session.delete(self.url + path, headers=self._headers))
 
  def reset_billing_project(self, billing_project):
  self.billing_project = billing_project