Add support for named entrypoints (#5215)

* feature: support named entrypoints in `wrangler (pages) deploy`

* chore: exclude `miniflare` from monorepo's Prettier config

* fix: allow `script`s without `scriptPath`s to import built-ins

* feature: service binding named entrypoints for single-instance JSRPC

* feature: direct socket named entrypoints for multi-instance JSRPC

* refactor: switch middleware to `external` services for dev registry

* feature: support binding to named entrypoints in `wrangler dev`

* feature: add middleware support to `WorkerEntrypoint`s

* feature: add API for starting isolated dev registry

* fix: ensure `url` and `cf` blob preserved across service bindings

* test: add tests for named entrypoints and RPC

* fixup! test: add tests for named entrypoints and RPC

Update error messages

* fix: improve error message for cross-session Durable Object RPC

* chore: move service binding assignment before Durable Objects

* fix: improve error message for RPC on not found service

* test: update deploy snapshot

* Add test for binding to own named entrypoint

* fix: allow named entrypoints to current worker

* Simplify cross-Worker Durable Object RPC error message

* Bump @cloudflare/workers-types@4.20240402.0

---------

Co-authored-by: bcoll <bcoll@cloudflare.com>

.changeset/afraid-jeans-tap.md

@@ -0,0 +1,7 @@
+---
+"wrangler": patch
+---
+
+fix: ensure request `url` and `cf` properties preserved across service bindings
+
+Previously, Wrangler could rewrite `url` and `cf` properties when sending requests via service bindings or Durable Object stubs. To match production behaviour, this change ensures these properties are preserved.

.changeset/brown-cycles-live.md

@@ -0,0 +1,9 @@
+---
+"miniflare": minor
+---
+
+feature: customisable unsafe direct sockets entrypoints
+
+Previously, Miniflare provided experimental `unsafeDirectHost` and `unsafeDirectPort` options for starting an HTTP server that pointed directly to a specific Worker. This change replaces these options with a single `unsafeDirectSockets` option that accepts an array of socket objects of the form `{ host?: string, port?: number, entrypoint?: string, proxy?: boolean }`. `host` defaults to `127.0.0.1`, `port` defaults to `0`, `entrypoint` defaults to `default`, and `proxy` defaults to `false`. This allows you to start HTTP servers for specific entrypoints of specific Workers. `proxy` controls the [`Style`](https://github.com/cloudflare/workerd/blob/af35f1e7b0f166ec4ca93a8bf7daeacda029f11d/src/workerd/server/workerd.capnp#L780-L789) of the socket.
+
+Note these sockets set the `capnpConnectHost` `workerd` option to `"miniflare-unsafe-internal-capnp-connect"`. `external` `serviceBindings` will set their `capnpConnectHost` option to the same value allowing RPC over multiple `Miniflare` instances. Refer to https://github.com/cloudflare/workerd/pull/1757 for more information.

.changeset/eight-seahorses-serve.md

@@ -0,0 +1,44 @@
+---
+"wrangler": minor
+---
+
+feature: support named entrypoints in service bindings
+
+This change allows service bindings to bind to a named export of another Worker. As an example, consider the following Worker named `bound`:
+
+```ts
+import { WorkerEntrypoint } from "cloudflare:workers";
+
+export class EntrypointA extends WorkerEntrypoint {
+	fetch(request) {
+		return new Response("Hello from entrypoint A!");
+	}
+}
+
+export const entrypointB: ExportedHandler = {
+	fetch(request, env, ctx) {
+		return new Response("Hello from entrypoint B!");
+	}
+};
+
+export default <ExportedHandler>{
+	fetch(request, env, ctx) {
+		return new Response("Hello from the default entrypoint!");
+	}
+};
+```
+
+Up until now, you could only bind to the `default` entrypoint. With this change, you can bind to `EntrypointA` or `entrypointB` too using the new `entrypoint` option:
+
+```toml
+[[services]]
+binding = "SERVICE"
+service = "bound"
+entrypoint = "EntrypointA"
+```
+
+To bind to named entrypoints with `wrangler pages dev`, use the `#` character:
+
+```shell
+$ wrangler pages dev --service=SERVICE=bound#EntrypointA
+```

.changeset/lazy-papayas-knock.md

@@ -0,0 +1,7 @@
+---
+"miniflare": patch
+---
+
+fix: allow `script`s without `scriptPath`s to import built-in modules
+
+Previously, if a string `script` option was specified with `modules: true` but without a corresponding `scriptPath`, all `import`s were forbidden. This change relaxes that restriction to allow imports of built-in `node:*`, `cloudflare:*` and `workerd:*` modules without a `scriptPath`.

.changeset/tidy-fans-speak.md

@@ -0,0 +1,48 @@
+---
+"miniflare": minor
+---
+
+feature: support named entrypoints for `serviceBindings`
+
+This change allows service bindings to bind to a named export of another Worker using designators of the form `{ name: string | typeof kCurrentWorker, entrypoint?: string }`. Previously, you could only bind to the `default` entrypoint. With this change, you can bind to any exported entrypoint.
+
+```ts
+import { kCurrentWorker, Miniflare } from "miniflare";
+
+const mf = new Miniflare({
+	workers: [
+		{
+			name: "a",
+			serviceBindings: {
+				A_RPC_SERVICE: { name: kCurrentWorker, entrypoint: "RpcEntrypoint" },
+				A_NAMED_SERVICE: { name: "a", entrypoint: "namedEntrypoint" },
+				B_NAMED_SERVICE: { name: "b", entrypoint: "anotherNamedEntrypoint" },
+			},
+			compatibilityFlags: ["rpc"],
+			modules: true,
+			script: `
+			import { WorkerEntrypoint } from "cloudflare:workers";
+			
+			export class RpcEntrypoint extends WorkerEntrypoint {
+				ping() { return "a:rpc:pong"; }
+			}
+			
+			export const namedEntrypoint = {
+				fetch(request, env, ctx) { return new Response("a:named:pong"); }
+			};
+			
+			...
+			`,
+		},
+		{
+			name: "b",
+			modules: true,
+			script: `
+			export const anotherNamedEntrypoint = {
+				fetch(request, env, ctx) { return new Response("b:named:pong"); }
+			};
+			`,
+		},
+	],
+});
+```

fixtures/additional-modules/package.json

@@ -12,7 +12,7 @@
 	},
 	"devDependencies": {
 		"@cloudflare/workers-tsconfig": "workspace:*",
-		"@cloudflare/workers-types": "^4.20240320.1",
+		"@cloudflare/workers-types": "^4.20240402.0",
 		"undici": "^5.28.3",
 		"wrangler": "workspace:*"
 	}

fixtures/entrypoints-rpc-tests/package.json

@@ -0,0 +1,15 @@
+{
+	"name": "entrypoints-rpc-tests",
+	"private": true,
+	"scripts": {
+		"test": "vitest run",
+		"test:ci": "vitest run",
+		"test:watch": "vitest"
+	},
+	"devDependencies": {
+		"@cloudflare/workers-tsconfig": "workspace:*",
+		"wrangler": "workspace:*",
+		"ts-dedent": "^2.2.0",
+		"undici": "^5.28.3"
+	}
+}