feat(cloudflare): add KV session storage support (#13514)

* feat(cloudflare): add KV session storage support

* Change code block language to JSONC

* Comments

* Use user-defined binding name

* Use createCodegenDir

* Remove unused import

1 files changed, 16 insertions, 1 deletions

diff --git a/packages/integrations/cloudflare/src/entrypoints/server.ts b/packages/integrations/cloudflare/src/entrypoints/server.ts
index 231dd87fa..b3cc6daf5 100644
--- a/packages/integrations/cloudflare/src/entrypoints/server.ts
+++ b/packages/integrations/cloudflare/src/entrypoints/server.ts
@@ -26,6 +26,16 @@ export interface Runtime<T extends object = object> {
 	};
 }
 
+declare global {
+	// This is not a real global, but is injected using Vite define to allow us to specify the session binding name in the config.
+	// eslint-disable-next-line no-var
+	var __ASTRO_SESSION_BINDING_NAME: string;
+
+	// Just used to pass the KV binding to unstorage.
+	// eslint-disable-next-line no-var
+	var __env__: Partial<Env>;
+}
+
 export function createExports(manifest: SSRManifest) {
 	const app = new App(manifest);
 
@@ -35,7 +45,12 @@ export function createExports(manifest: SSRManifest) {
 		context: ExecutionContext,
 	) => {
 		const { pathname } = new URL(request.url);
-
+		const bindingName = globalThis.__ASTRO_SESSION_BINDING_NAME;
+		// Assigning the KV binding to globalThis allows unstorage to access it for session storage.
+		// unstorage checks in globalThis and globalThis.__env__ for the binding.
+		globalThis.__env__ ??= {};
+		globalThis.__env__[bindingName] = env[bindingName];
+		
 		// static assets fallback, in case default _routes.json is not used
 		if (manifest.assets.has(pathname)) {
 			return env.ASSETS.fetch(request.url.replace(/\.html$/, ''));