Email Workers local dev and send_email binding (#8375)

* feat: Add support for Email Workers in local dev * Update fixtures/email-worker/src/index.ts * Update fixtures/email-worker/src/index.ts * Update fixtures/email-worker/src/index.ts * Update fixtures/email-worker/src/index.ts * Update packages/miniflare/src/plugins/core/index.ts * Cleanup & address comments * fix Miniflare tests * more tests * fixups * fix logging * fix lint * fix e2e * make e2e tests a bit more reliable * Add comment about logRequests * Cleanup fixture * Add namespacing * Undo weird typing stuff * cleanup * add deprecation warning for mf/scheduled * remove test * more comments * build * fix lockfile * tweak test for Windows * update workers-types dependency in email-worker fixture * fixups --------- Co-authored-by: Carmen Popoviciu <cpopoviciu@cloudflare.com> Co-authored-by: Peter Bacon Darwin <pbacondarwin@cloudflare.com>

Author: 3 people

.changeset/neat-planes-call.md

@@ -0,0 +1,6 @@
+---
+"miniflare": minor
+"wrangler": minor
+---
+
+Add support for email local dev and send_email binding

fixtures/email-worker/package.json

@@ -0,0 +1,17 @@
+{
+"name": "email-worker",
+"private": true,
+"scripts": {
+"deploy": "wrangler deploy",
+"start": "wrangler dev"
+},
+"devDependencies": {
+"@cloudflare/workers-types": "^4.20250317.0",
+"@types/mimetext": "^2.0.4",
+"mimetext": "^3.0.27",
+"wrangler": "workspace:*"
+},
+"volta": {
+"extends": "../../package.json"
+}
+}

fixtures/email-worker/src/index.ts

@@ -0,0 +1,48 @@
+import { EmailMessage } from "cloudflare:email";
+import { env, WorkerEntrypoint } from "cloudflare:workers";
+import { createMimeMessage } from "mimetext";
+
+export default class extends WorkerEntrypoint<Env> {
+async fetch(request: Request): Promise<Response> {
+const url = new URL(request.url);
+if (url.pathname === "/error") throw new Error("Hello Error");
+
+if (url.pathname === "/send") {
+const msg = createMimeMessage();
+msg.setSender({ name: "GPT-4", addr: "sender@penalosa.cloud" });
+msg.setRecipient("else@example.com");
+msg.setSubject("An email generated in a Worker");
+msg.addMessage({
+contentType: "text/plain",
+data: "Congratulations, you just sent an email from a Worker.",
+});
+const m = new EmailMessage(
+"sender@penalosa.cloud",
+"else@example.com",
+msg.asRaw()
+);
+await this.env.LIST_SEND.send(m);
+}
+
+return new Response("Hello World!");
+}
+async email(message: ForwardableEmailMessage) {
+console.log("hello");
+const msg = createMimeMessage();
+msg.setHeader("In-Reply-To", message.headers.get("Message-ID")!);
+msg.setSender(message.to);
+msg.setRecipient(message.from);
+msg.setSubject("An email generated in a Worker");
+msg.addMessage({
+contentType: "text/plain",
+data: `Congratulations, you just sent an email from a Worker.`,
+});
+
+const m = new EmailMessage(message.to, message.from, msg.asRaw());
+await message.forward(
+"samuel@macleod.space",
+new Headers({ hello: "world" })
+);
+await message.reply(m);
+}
+}

fixtures/email-worker/tsconfig.json

@@ -0,0 +1,14 @@
+{
+"compilerOptions": {
+"target": "es2021",
+"lib": ["es2021"],
+"module": "es2022",
+"moduleResolution": "bundler",
+"types": ["@cloudflare/workers-types"],
+"noEmit": true,
+"isolatedModules": true,
+"forceConsistentCasingInFileNames": true,
+"strict": true,
+"skipLibCheck": true
+}
+}

fixtures/email-worker/worker-configuration.d.ts

@@ -0,0 +1,7 @@
+// Generated by Wrangler by running `wrangler types --x-include-runtime`
+
+interface Env extends Env {
+UNBOUND_SEND: SendEmail;
+SPECIFIC_SEND: SendEmail;
+LIST_SEND: SendEmail;
+}

fixtures/email-worker/wrangler.toml

@@ -0,0 +1,11 @@
+name = "email-to-rss"
+main = "src/index.ts"
+compatibility_date = "2025-02-14"
+
+compatibility_flags = [ "nodejs_compat" ]
+
+send_email = [
+ {name = "UNBOUND_SEND"},
+ {name = "SPECIFIC_SEND", destination_address = "something@example.com"},
+ {name = "LIST_SEND", allowed_destination_addresses = ["something@example.com", "else@example.com"]},
+]

package.json

@@ -81,7 +81,8 @@
 "@cloudflare/component-listbox@1.10.6": "patches/@cloudflare__component-listbox@1.10.6.patch",
 "pg@8.11.3": "patches/pg@8.11.3.patch",
 "toucan-js@3.3.1": "patches/toucan-js@3.3.1.patch",
-"toucan-js@4.0.0": "patches/toucan-js@4.0.0.patch"
+"toucan-js@4.0.0": "patches/toucan-js@4.0.0.patch",
+"postal-mime": "patches/postal-mime.patch"
 }
 }
 }

packages/miniflare/package.json

@@ -88,9 +88,11 @@
 "http-cache-semantics": "^4.1.0",
 "kleur": "^4.1.5",
 "mime": "^3.0.0",
+"postal-mime": "^2.4.3",
 "pretty-bytes": "^6.0.0",
 "rimraf": "catalog:default",
 "source-map": "^0.6.1",
+"ts-dedent": "^2.2.0",
 "typescript": "catalog:default",
 "which": "^2.0.2"
 },

packages/miniflare/src/index.ts

@@ -2,6 +2,7 @@ import assert from "assert";
 import crypto from "crypto";
 import { Abortable } from "events";
 import fs from "fs";
+import { mkdir, writeFile } from "fs/promises";
 import http from "http";
 import net from "net";
 import os from "os";
@@ -982,6 +983,17 @@ export class Miniflare {
 if (!colors$.enabled) message = stripAnsi(message);
 this.#log.logWithLevel(logLevel, message);
 response = new Response(null, { status: 204 });
+} else if (url.pathname === "/core/store-temp-file") {
+const prefix = url.searchParams.get("prefix");
+const folder = prefix ? `files/${prefix}` : "files";
+await mkdir(path.join(this.#tmpPath, folder), { recursive: true });
+const filePath = path.join(
+this.#tmpPath,
+folder,
+`${crypto.randomUUID()}.${url.searchParams.get("extension") ?? "txt"}`
+);
+await writeFile(filePath, await request.text());
+response = new Response(filePath, { status: 200 });
 }
 } catch (e: any) {
 this.#log.error(e);
@@ -1547,11 +1559,13 @@ export class Miniflare {
 const ready = initial ? "Ready" : "Updated and ready";
 
 const urlSafeHost = getURLSafeHost(configuredHost);
-this.#log.info(
-`${ready} on ${secure ? "https" : "http"}://${urlSafeHost}:${entryPort}`
-);
+if (this.#sharedOpts.core.logRequests) {
+this.#log.info(
+`${ready} on ${secure ? "https" : "http"}://${urlSafeHost}:${entryPort}`
+);
+}
 
-if (initial) {
+if (initial && this.#sharedOpts.core.logRequests) {
 const hosts: string[] = [];
 if (configuredHost === "::" || configuredHost === "*") {
 hosts.push("localhost");

packages/miniflare/src/plugins/core/index.ts

@@ -210,6 +210,10 @@ export const CoreSharedOptionsSchema = z.object({
 unsafeModuleFallbackService: ServiceFetchSchema.optional(),
 // Keep blobs when deleting/overwriting keys, required for stacked storage
 unsafeStickyBlobs: z.boolean().optional(),
+// Enable directly triggering user Worker handlers with paths like `/cdn-cgi/handler/scheduled`
+unsafeTriggerHandlers: z.boolean().optional(),
+// Enable logging requests
+logRequests: z.boolean().default(true),
 });
 
 export const CORE_PLUGIN_NAME = "core";
@@ -746,6 +750,14 @@ export function getGlobalServices({
 const serviceEntryBindings: Worker_Binding[] = [
 WORKER_BINDING_SERVICE_LOOPBACK, // For converting stack-traces to pretty-error pages
 { name: CoreBindings.JSON_ROUTES, json: JSON.stringify(routes) },
+{
+name: CoreBindings.TRIGGER_HANDLERS,
+json: JSON.stringify(!!sharedOptions.unsafeTriggerHandlers),
+},
+{
+name: CoreBindings.LOG_REQUESTS,
+json: JSON.stringify(!!sharedOptions.logRequests),
+},
 { name: CoreBindings.JSON_CF_BLOB, json: JSON.stringify(sharedOptions.cf) },
 { name: CoreBindings.JSON_LOG_LEVEL, json: JSON.stringify(log.level) },
 {
@@ -795,13 +807,8 @@ export function getGlobalServices({
 name: SERVICE_ENTRY,
 worker: {
 modules: [{ name: "entry.worker.js", esModule: SCRIPT_ENTRY() }],
-compatibilityDate: "2023-04-04",
-compatibilityFlags: [
-"nodejs_compat",
-"service_binding_extra_handlers",
-"brotli_content_encoding",
-"rpc",
-],
+compatibilityDate: "2025-03-17",
+compatibilityFlags: ["nodejs_compat", "service_binding_extra_handlers"],
 bindings: serviceEntryBindings,
 durableObjectNamespaces: [
 {