Merge pull request #19 from volfpeter/response-header-support-in-core…

…-decorators

#18 - Response header support in core decorators

README.md

@@ -18,6 +18,7 @@ Key features:
 - Built-in **Jinja2 templating support** (even with multiple template folders).
 - Gives the rendering engine **access to all dependencies** of the decorated route.
 - FastAPI **routes will keep working normally by default** if they receive **non-HTMX** requests, so the same route can serve data and render HTML at the same time.
+- **Response headers** you set in your routes are kept after rendering, as you would expect in FastAPI.
 - **Correct typing** makes it possible to apply other (typed) decorators to your routes.
 - Works with both **sync** and **async routes**.
 

docs/index.md

@@ -18,6 +18,7 @@ Key features:
 - Built-in **Jinja2 templating support** (even with multiple template folders).
 - Gives the rendering engine **access to all dependencies** of the decorated route.
 - FastAPI **routes will keep working normally by default** if they receive **non-HTMX** requests, so the same route can serve data and render HTML at the same time.
+- **Response headers** you set in your routes are kept after rendering, as you would expect in FastAPI.
 - **Correct typing** makes it possible to apply other (typed) decorators to your routes.
 - Works with both **sync** and **async routes**.
 

examples/custom-rendering/custom_rendering_app.py

@@ -1,6 +1,6 @@
 from typing import Annotated, Any
 
-from fastapi import Depends, FastAPI, Request
+from fastapi import Depends, FastAPI, Request, Response
 
 from fasthx import hx, page
 
@@ -39,7 +39,8 @@ def index() -> None:
 
 @app.get("/htmx-or-data")
 @hx(render_user_list)
-def htmx_or_data(random_number: DependsRandomNumber) -> list[dict[str, str]]:
+def htmx_or_data(random_number: DependsRandomNumber, response: Response) -> list[dict[str, str]]:
+    response.headers["my-response-header"] = "works"
     return [{"name": "Joe"}]
 
 

examples/jinja-rendering/jinja_app.py

@@ -1,6 +1,6 @@
 import os
 
-from fastapi import FastAPI
+from fastapi import FastAPI, Response
 from fastapi.templating import Jinja2Templates
 from pydantic import BaseModel
 
@@ -27,8 +27,9 @@ class User(BaseModel):
 
 @app.get("/user-list")
 @jinja.hx("user-list.html")  # Render the response with the user-list.html template.
-def htmx_or_data() -> tuple[User, ...]:
+def htmx_or_data(response: Response) -> tuple[User, ...]:
     """This route can serve both JSON and HTML, depending on if the request is an HTMX request or not."""
+    response.headers["my-response-header"] = "works"
     return (
         User(first_name="Peter", last_name="Volf"),
         User(first_name="Hasan", last_name="Tasan"),

fasthx/core_decorators.py

@@ -8,7 +8,7 @@
 
 from .dependencies import DependsHXRequest
 from .typing import HTMLRenderer, MaybeAsyncFunc, P, T
-from .utils import append_to_signature, execute_maybe_sync_func
+from .utils import append_to_signature, execute_maybe_sync_func, get_response
 
 
 def hx(
@@ -40,8 +40,13 @@ async def wrapper(
             if __hx_request is None or isinstance(result, Response):
                 return result
 
+            response = get_response(kwargs)
             rendered = await execute_maybe_sync_func(render, result, context=kwargs, request=__hx_request)
-            return HTMLResponse(rendered) if isinstance(rendered, str) else rendered
+            return (
+                HTMLResponse(rendered, headers=None if response is None else response.headers)
+                if isinstance(rendered, str)
+                else rendered
+            )
 
         return append_to_signature(
             wrapper,  # type: ignore[arg-type]
@@ -72,10 +77,15 @@ async def wrapper(*args: P.args, __page_request: Request, **kwargs: P.kwargs) ->
             if isinstance(result, Response):
                 return result
 
+            response = get_response(kwargs)
             rendered: str | Response = await execute_maybe_sync_func(
                 render, result, context=kwargs, request=__page_request
             )
-            return HTMLResponse(rendered) if isinstance(rendered, str) else rendered
+            return (
+                HTMLResponse(rendered, headers=None if response is None else response.headers)
+                if isinstance(rendered, str)
+                else rendered
+            )
 
         return append_to_signature(
             wrapper,  # type: ignore[arg-type]

fasthx/utils.py

@@ -1,8 +1,9 @@
 import inspect
 from asyncio import iscoroutinefunction
-from collections.abc import Callable
-from typing import cast
+from collections.abc import Callable, Mapping
+from typing import Any, cast
 
+from fastapi import Response
 from fastapi.concurrency import run_in_threadpool
 
 from .typing import MaybeAsyncFunc, P, T
@@ -45,3 +46,17 @@ async def execute_maybe_sync_func(func: MaybeAsyncFunc[P, T], *args: P.args, **k
         return await func(*args, **kwargs)  # type: ignore[no-any-return]
 
     return await run_in_threadpool(cast(Callable[P, T], func), *args, **kwargs)
+
+
+def get_response(kwargs: Mapping[str, Any]) -> Response | None:
+    """
+    Returns the first `Response` instance from the values in `kwargs` (if there is one).
+
+    Arguments:
+        kwargs: The keyword arguments from which the `Response` should be returned.
+    """
+    for val in kwargs.values():
+        if isinstance(val, Response):
+            return val
+
+    return None

pyproject.toml

@@ -1,6 +1,6 @@
 [tool.poetry]
 name = "fasthx"
-version = "0.2402.2"
+version = "0.2403.0"
 description = "FastAPI data APIs with HTMX support."
 authors = ["Peter Volf <[email protected]>"]
 readme = "README.md"

tests/test_core_decorators.py

@@ -1,7 +1,7 @@
 from typing import Any
 
 import pytest
-from fastapi import FastAPI, Request
+from fastapi import FastAPI, Request, Response
 from fastapi.testclient import TestClient
 
 from fasthx import hx, page
@@ -10,9 +10,6 @@
 
 
 def render_user_list(result: list[User], *, context: dict[str, Any], request: Request) -> str:
-    # Test that the hx() decorator's inserted params are not in context.
-    assert len(context) == 1
-
     # Test that the value of the DependsRandomNumber dependency is in the context.
     random_number = context["random_number"]
     assert random_number == 4
@@ -35,7 +32,8 @@ def index(random_number: DependsRandomNumber) -> list[User]:
 
     @app.get("/htmx-or-data")
     @hx(render_user_list)
-    def htmx_or_data(random_number: DependsRandomNumber) -> list[User]:
+    def htmx_or_data(random_number: DependsRandomNumber, response: Response) -> list[User]:
+        response.headers["test-header"] = "exists"
         return users
 
     @app.get("/htmx-only")  # type: ignore # TODO: figure out why mypy doesn't see the correct type.
@@ -52,20 +50,20 @@ def hx_client(hx_app: FastAPI) -> TestClient:
 
 
 @pytest.mark.parametrize(
-    ("route", "headers", "status", "expected"),
+    ("route", "headers", "status", "expected", "response_headers"),
     (
         # page() - always renders the HTML result.
-        ("/", {"HX-Request": "true"}, 200, user_list_html),
-        ("/", None, 200, user_list_html),
-        ("/", {"HX-Request": "false"}, 200, user_list_html),
+        ("/", {"HX-Request": "true"}, 200, user_list_html, {}),
+        ("/", None, 200, user_list_html, {}),
+        ("/", {"HX-Request": "false"}, 200, user_list_html, {}),
         # hx() - returns JSON for non-HTMX requests.
-        ("/htmx-or-data", {"HX-Request": "true"}, 200, user_list_html),
-        ("/htmx-or-data", None, 200, user_list_json),
-        ("/htmx-or-data", {"HX-Request": "false"}, 200, user_list_json),
+        ("/htmx-or-data", {"HX-Request": "true"}, 200, user_list_html, {"test-header": "exists"}),
+        ("/htmx-or-data", None, 200, user_list_json, {"test-header": "exists"}),
+        ("/htmx-or-data", {"HX-Request": "false"}, 200, user_list_json, {"test-header": "exists"}),
         # hy(no_data=True) - raises exception for non-HTMX requests.
-        ("/htmx-only", {"HX-Request": "true"}, 200, user_list_html),
-        ("/htmx-only", None, 400, ""),
-        ("/htmx-only", {"HX-Request": "false"}, 400, ""),
+        ("/htmx-only", {"HX-Request": "true"}, 200, user_list_html, {}),
+        ("/htmx-only", None, 400, "", {}),
+        ("/htmx-only", {"HX-Request": "false"}, 400, "", {}),
     ),
 )
 def test_hx_and_page(
@@ -74,6 +72,7 @@ def test_hx_and_page(
     headers: dict[str, str] | None,
     status: int,
     expected: str,
+    response_headers: dict[str, str],
 ) -> None:
     response = hx_client.get(route, headers=headers)
     assert response.status_code == status
@@ -82,3 +81,5 @@ def test_hx_and_page(
 
     result = response.text
     assert result == expected
+
+    assert all((response.headers.get(key) == value) for key, value in response_headers.items())