smtp: allow cc/bcc-only messages

Readme.md

@@ -189,19 +189,18 @@ const options = {
 ## new message.Message(headers)
 
 ```js
-// headers is an object with the following recognized keys:
+// headers is an object with the following recognized schema:
 const headers = {
-	// required
 	from, // sender of the format (address or name <address> or "name" <address>)
 	to, // recipients (same format as above), multiple recipients are separated by a comma
-
-	// optional
-	text, // text of the email
 	cc, // carbon copied recipients (same format as above)
 	bcc, // blind carbon copied recipients (same format as above)
+	text, // text of the email
 	subject, // string subject of the email
 	attachment, // one attachment or array of attachments
 };
+// the `from` field is required.
+// at least one `to`, `cc`, or `bcc` header is also required.
 // you can also add whatever other headers you want.
 ```
 

smtp/client.ts

@@ -42,7 +42,10 @@ export class Client {
 	 * @param {function(err: Error, msg: Message): void} callback sss
 	 * @returns {void}
 	 */
-	public send(msg: Message, callback: (err: Error, msg: Message) => void) {
+	public send(
+		msg: Message,
+		callback: (err: Error | null, msg: Message) => void
+	) {
 		const message: Message | null =
 			msg instanceof Message
 				? msg
@@ -59,7 +62,7 @@ export class Client {
 			if (valid) {
 				const stack = {
 					message,
-					to: addressparser(message.header.to),
+					to: [] as ReturnType<typeof addressparser>,
 					from: addressparser(message.header.from)[0].address,
 					callback: (
 						callback ||
@@ -69,7 +72,11 @@ export class Client {
 					).bind(this),
 				} as MessageStack;
 
-				if (message.header.cc) {
+				if (typeof message.header.to === 'string') {
+					stack.to = addressparser(message.header.to);
+				}
+
+				if (typeof message.header.cc === 'string') {
 					stack.to = stack.to.concat(
 						addressparser(message.header.cc).filter(
 							(x) => stack.to.some((y) => y.address === x.address) === false
@@ -77,7 +84,7 @@ export class Client {
 					);
 				}
 
-				if (message.header.bcc) {
+				if (typeof message.header.bcc === 'string') {
 					stack.to = stack.to.concat(
 						addressparser(message.header.bcc).filter(
 							(x) => stack.to.some((y) => y.address === x.address) === false
@@ -85,6 +92,10 @@ export class Client {
 					);
 				}
 
+				if (stack.to.length === 0) {
+					return callback(new Error('No recipients found in message'), msg);
+				}
+
 				if (
 					message.header['return-path'] &&
 					addressparser(message.header['return-path']).length

smtp/message.ts

@@ -116,6 +116,17 @@ export class Message {
 	public readonly text?: string;
 	public alternative: AlternateMessageAttachment | null = null;
 
+	/**
+	 * Construct an rfc2822-compliant message object.
+	 *
+	 * Special notes:
+	 * - The `from` field is required.
+	 * - At least one `to`, `cc`, or `bcc` header is also required.
+	 * - You can also add whatever other headers you want.
+	 *
+	 * @see https://tools.ietf.org/html/rfc2822
+	 * @param {Partial<MessageHeaders>} headers Message headers
+	 */
 	constructor(headers: Partial<MessageHeaders>) {
 		for (const header in headers) {
 			// allow user to override default content-type to override charset or send a single non-text message
@@ -143,7 +154,6 @@ export class Message {
 				);
 			} else {
 				// allow any headers the user wants to set??
-				// if(/cc|bcc|to|from|reply-to|sender|subject|date|message-id/i.test(header))
 				this.header[header.toLowerCase()] = headers[header];
 			}
 		}
@@ -196,12 +206,19 @@ export class Message {
 	 * @returns {void}
 	 */
 	public valid(callback: (arg0: boolean, arg1?: string) => void) {
-		if (!this.header.from) {
-			callback(false, 'message does not have a valid sender');
+		if (typeof this.header.from !== 'string') {
+			callback(false, 'Message must have a `from` header');
 		}
 
-		if (!(this.header.to || this.header.cc || this.header.bcc)) {
-			callback(false, 'message does not have a valid recipient');
+		if (
+			typeof this.header.to !== 'string' &&
+			typeof this.header.cc !== 'string' &&
+			typeof this.header.bcc !== 'string'
+		) {
+			callback(
+				false,
+				'Message must have at least one `to`, `cc`, or `bcc` header'
+			);
 		} else if (this.attachments.length === 0) {
 			callback(true, undefined);
 		} else {

test/authplain.ts

@@ -69,6 +69,65 @@ test.cb('authorize plain', (t) => {
 	);
 });
 
+test.cb(
+	'Client refuses to send message without `to`, `cc`, or `bcc` header',
+	(t) => {
+		const msg = {
+			subject: 'this is a test TEXT message from emailjs',
+			from: 'piglet@gmail.com',
+			text: "It is hard to be brave when you're only a Very Small Animal.",
+		};
+		client.send(new m.Message(msg), (err) => {
+			t.true(err instanceof Error);
+			t.is(
+				err?.message,
+				'Message must have at least one `to`, `cc`, or `bcc` header'
+			);
+			t.end();
+		});
+	}
+);
+
+test.cb('Client allows message with only `cc` header', (t) => {
+	const msg = {
+		subject: 'this is a test TEXT message from emailjs',
+		from: 'piglet@gmail.com',
+		cc: 'pooh@gmail.com',
+		text: "It is hard to be brave when you're only a Very Small Animal.",
+	};
+
+	send(
+		new m.Message(msg),
+		(mail) => {
+			t.is(mail.text, msg.text + '\n\n\n');
+			t.is(mail.subject, msg.subject);
+			t.is(mail.from?.text, msg.from);
+			t.is(mail.cc?.text, msg.cc);
+		},
+		t.end
+	);
+});
+
+test.cb('Client allows message with only `bcc` header', (t) => {
+	const msg = {
+		subject: 'this is a test TEXT message from emailjs',
+		from: 'piglet@gmail.com',
+		bcc: 'pooh@gmail.com',
+		text: "It is hard to be brave when you're only a Very Small Animal.",
+	};
+
+	send(
+		new m.Message(msg),
+		(mail) => {
+			t.is(mail.text, msg.text + '\n\n\n');
+			t.is(mail.subject, msg.subject);
+			t.is(mail.from?.text, msg.from);
+			t.is(mail.bcc?.text, undefined);
+		},
+		t.end
+	);
+});
+
 test('Client constructor throws if `password` supplied without `user`', (t) => {
 	t.notThrows(() => new c.Client({ user: 'anything', password: 'anything' }));
 	t.throws(() => new c.Client({ password: 'anything' }));