Expose getFetchState() from astro/hono

.changeset/expose-get-fetch-state.md

@@ -0,0 +1,24 @@
+---
+'astro': minor
+---
+
+Exposes `getFetchState()` from `astro/hono` as a public API
+
+The `getFetchState()` function retrieves or lazily creates a `FetchState` from a Hono context object. This allows third-party packages to build Hono middleware that interacts with Astro's per-request state, giving the `astro/hono` API the same extensibility as `astro/fetch`.
+
+```ts
+import { Hono } from 'hono';
+import { getFetchState, pages } from 'astro/hono';
+
+const app = new Hono();
+
+app.use(async (context, next) => {
+  const state = getFetchState(context);
+  state.locals.message = 'Hello from custom middleware';
+  await next();
+});
+
+app.use(pages());
+
+export default app;
+```

packages/astro/src/core/hono/index.ts

@@ -30,7 +30,7 @@ type HonoMiddlewareHandler = (
 	next: () => Promise<void>,
 ) => Promise<Response | void>;
 
-function getFetchState(context: HonoContextLike): FetchState {
+export function getFetchState(context: HonoContextLike): FetchState {
 	const state = context.get?.(FETCH_STATE_KEY) as FetchState | undefined;
 	if (state) {
 		return state;

packages/astro/test/units/hono/index.test.ts

@@ -3,7 +3,7 @@ import { describe, it } from 'node:test';
 import { Hono } from 'hono';
 import { FetchState } from '../../../dist/core/fetch/fetch-state.js';
 import { appSymbol } from '../../../dist/core/constants.js';
-import { astro } from '../../../dist/core/hono/index.js';
+import { astro, getFetchState } from '../../../dist/core/hono/index.js';
 import { createComponent, render } from '../../../dist/runtime/server/index.js';
 import { createPage, createTestApp } from '../mocks.ts';
 
@@ -55,3 +55,55 @@ describe('astro() Hono middleware', () => {
 		assert.match(await response.text(), /<h1>from stashed FetchState<\/h1>/);
 	});
 });
+
+describe('getFetchState()', () => {
+	it('creates a new FetchState from the Hono context', async () => {
+		const astroApp = createTestApp([createPage(page, { route: '/' })]);
+		const hono = createHonoApp(astroApp);
+		let capturedState: FetchState | undefined;
+		hono.use(async (context, next) => {
+			capturedState = getFetchState(context);
+			await next();
+		});
+		hono.use(astro());
+
+		const response = await hono.fetch(new Request('http://example.com/'));
+
+		assert.equal(response.status, 200);
+		assert.ok(capturedState instanceof FetchState, 'getFetchState should return a FetchState');
+	});
+
+	it('returns the same FetchState on subsequent calls', async () => {
+		const astroApp = createTestApp([createPage(page, { route: '/' })]);
+		const hono = createHonoApp(astroApp);
+		let firstState: FetchState | undefined;
+		let secondState: FetchState | undefined;
+		hono.use(async (context, next) => {
+			firstState = getFetchState(context);
+			secondState = getFetchState(context);
+			await next();
+		});
+		hono.use(astro());
+
+		await hono.fetch(new Request('http://example.com/'));
+
+		assert.ok(firstState);
+		assert.equal(firstState, secondState, 'getFetchState should return the same instance');
+	});
+
+	it('allows custom middleware to set locals via getFetchState', async () => {
+		const astroApp = createTestApp([createPage(page, { route: '/' })]);
+		const hono = createHonoApp(astroApp);
+		hono.use(async (context, next) => {
+			const state = getFetchState(context);
+			state.locals = { message: 'set via getFetchState' } as any;
+			await next();
+		});
+		hono.use(astro());
+
+		const response = await hono.fetch(new Request('http://example.com/'));
+
+		assert.equal(response.status, 200);
+		assert.match(await response.text(), /<h1>set via getFetchState<\/h1>/);
+	});
+});