Feat/add render component method to htmy

fasthx/htmy.py

@@ -177,8 +177,30 @@ def page(
             else self._make_error_render_function(error_component_selector),
         )
 
+    async def render_component(self, component: h.Component, request: Request) -> str:
+        """
+        Renders the given component.
+
+        This method is useful for rendering components directly, outside of the context of a route
+        (meaning no access to route parameters), for example in exception handlers.
+
+        The method adds all the usual data to the `htmy` rendering context, including the result of
+        all request processors. There is no access to route parameters though, so while `RouteParams`
+        will be in the context, it will be empty.
+
+        Arguments:
+            component: The component to render.
+            request: The current request.
+
+        Returns:
+            The rendered component.
+        """
+        return await self.htmy.render(component, self._make_render_context(request, {}))
+
     def _make_render_function(self, component_selector: HTMYComponentSelector[T]) -> HTMLRenderer[T]:
-        """Creates a render function that uses the given component selector."""
+        """
+        Creates a render function that uses the given component selector.
+        """
 
         async def render(result: T, *, context: dict[str, Any], request: Request) -> str:
             component = (
@@ -193,7 +215,9 @@ async def render(result: T, *, context: dict[str, Any], request: Request) -> str
     def _make_error_render_function(
         self, component_selector: HTMYComponentSelector[Exception]
     ) -> HTMLRenderer[Exception]:
-        """Creates an error renderer function that uses the given component selector."""
+        """
+        Creates an error renderer function that uses the given component selector.
+        """
 
         async def render(result: Exception, *, context: dict[str, Any], request: Request) -> str:
             component = (
@@ -206,7 +230,16 @@ async def render(result: Exception, *, context: dict[str, Any], request: Request
         return render
 
     def _make_render_context(self, request: Request, route_params: dict[str, Any]) -> h.Context:
-        """Creates the HTMY rendering context."""
+        """
+        Creates the `htmy` rendering context for the given request and route parameters.
+
+        Arguments:
+            request: The current request.
+            route_params: The route parameters.
+
+        Returns:
+            The `htmy` rendering context.
+        """
         # Add the current request to the context.
         result = CurrentRequest.to_context(request)
 

pyproject.toml

@@ -1,6 +1,6 @@
 [tool.poetry]
 name = "fasthx"
-version = "2.2.1"
+version = "2.3.0"
 description = "FastAPI server-side rendering with built-in HTMX support."
 authors = ["Peter Volf <[email protected]>"]
 readme = "README.md"

tests/test_htmy.py

@@ -1,5 +1,6 @@
 import pytest
-from fastapi import FastAPI, Response
+from fastapi import FastAPI, Request, Response
+from fastapi.responses import HTMLResponse
 from fastapi.testclient import TestClient
 
 from fasthx.htmy import HTMY, ComponentHeader
@@ -14,7 +15,7 @@
     users,
 )
 from .errors import RenderedError
-from .htmy_components import HelloWorld, Profile, RequestProcessors, UserList
+from .htmy_components import HelloWorld, Profile, RequestProcessors, UserList, UserListItem
 
 billy_html_header = "<h1 >Billy Shears (active=True)</h1>"
 billy_html_paragraph = "<p >Billy Shears (active=True)</p>"
@@ -117,6 +118,10 @@ def error_page(response: Response, kind: str | None = None) -> None:
     def global_no_data() -> list[User]:
         return []
 
+    @app.get("/render-component")
+    async def render_component(request: Request) -> HTMLResponse:
+        return HTMLResponse(await htmy.render_component(UserListItem(billy), request))
+
     return app
 
 
@@ -191,6 +196,8 @@ def htmy_client(htmy_app: FastAPI) -> TestClient:
         ("/error-page/value-error", None, 500, "None", {}),
         # Globally disabled data responses
         ("/global-no-data", None, 400, "", {}),
+        # Direct component rendering
+        ("/render-component", None, 200, "<li >Billy Shears (active=True)</li>", {}),
     ),
 )
 def test_htmy(