Fix 234 (#271)

* Fix envelope handling

* Updated documentation

* Update main.js

Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>

* Update README.md

Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>

* Implemented review suggestions

* Implemented review suggestions

* Implemented review suggestions

* Use nodemailer's addressparser instead of regular expressions

* Updated README regarding address formats

* Updated README regarding address formats

* Update README.md

Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>

* Use addressparser regardless of envelopeX ist set or not.

---------

Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>

README.md

@@ -27,54 +27,86 @@ Some features:
     #  * smtp://user:password@server:port
     #  * smtp+starttls://user:password@server:port
     connection_url: ${{secrets.MAIL_CONNECTION}}
+
     # Required mail server address if not connection_url:
     server_address: smtp.gmail.com
+
     # Server port, default 25:
     server_port: 465
+
     # Optional whether this connection use TLS (default is true if server_port is 465)
     secure: true
+
     # Optional (recommended) mail server username:
     username: ${{secrets.MAIL_USERNAME}}
+
     # Optional (recommended) mail server password:
     password: ${{secrets.MAIL_PASSWORD}}
+
     # Required mail subject:
     subject: Github Actions job result
-    # Optional recipients' addresses:
-    to: obiwan@example.com,yoda@example.com
-    # Required sender (Either: "Plain Simple Name <user@doma.in>" or just "user@doma.in" (without the <>))
-    # Important: '<' and '>' are special chars in yaml. Therefore this string should be quoted
+
+    # Optional recipients. Separate multiple addresses by a comma (possibly surrounded by whitespace):
+    to: obiwan@example.com, yoda@example.com
+
+    # Required sender (supported formats: see "Supported address formats" below)
     from: 'Luke Skywalker <user@example.com>'
+
     # Optional plain body:
     body: Build job of ${{github.repository}} completed successfully!
+
     # Optional HTML body read from file:
     html_body: file://README.html
-    # Optional carbon copy recipients:
-    cc: kyloren@example.com,leia@example.com
-    # Optional blind carbon copy recipients:
-    bcc: r2d2@example.com,hansolo@example.com
+
+    # Optional carbon copy recipients. Separate multiple addresses by a comma (possibly surrounded by whitespace):
+    cc: 'kyloren@example.com, "Her Majesty, Princess Leia" <leia@example.com>'
+
+    # Optional blind carbon copy recipients. Separate multiple addresses by a comma (possibly surrounded by whitespace):
+    bcc: r2d2@example.com, hansolo@example.com
+
     # Optional recipient of the email response:
     reply_to: luke@example.com
+
     # Optional Message ID this message is replying to:
-    in_reply_to: <random-luke@example.com>
+    in_reply_to: '<3cc627c8-6181-453b-d90b-04aae9e23b21@github.com>'
+
     # Optional unsigned/invalid certificates allowance:
     ignore_cert: true
+
     # Optional converting Markdown to HTML (set content_type to text/html too):
     convert_markdown: true
+
     # Optional attachments:
     attachments: attachments.zip,git.diff,./dist/static/*.js
+
     # Optional priority: 'high', 'normal' (default) or 'low'
     priority: low
+
     # Optional custom headers:
     headers: '{"X-Priority": "3 (Normal)", "X-My-Header": "MyValue"}'
+
     # Optional nodemailerlog: true/false
     nodemailerlog: false
-    # Optional nodemailerdebug: true/false if true lognodem will also be set true
+
+    # Optional nodemailerdebug: true/false if true nodemailerlog will also be set true
     nodemailerdebug: false
+
     # Optional custom SMTP MAIL FROM address (overrides username):
     envelope_from: mailer@example.com
-    # Optional custom SMTP RCPT TO addresses (overrides to, cc, bcc):
-    envelope_to: mailer@example.com,admin@example.com
+
+    # Optional custom SMTP RCPT TO addresses (overrides to, cc, bcc). Separate multiple addresses by a comma (possibly surrounded by whitespace):
+    envelope_to: mailer@example.com, admin@example.com
 ```
+### Remark for `envelope_from` and `envelope_to`
+
+[nodemailer](https://nodemailer.com/) (the node module that does the actual sending) requires that if the optional custom envelope is used, **both** its attributes `from` and `to` must be set. To facilitate setting only one of `envelope_from` or `envelope_to`, this action sets the other one from the regular message fields in the following way:
+
+* If only `envelope_from` is set, `envelope_to` will be set to the concatenation of `to`, `cc` and `bcc` (with duplicates removed).
+* If only `envelope_to` is set, `envelope_from` will be set to the address specified in `from`.
+
+### Supported address formats
+This action now uses nodemailer's addressparser. The supported address formats are described [here](https://nodemailer.com/message/addresses).
+Mail addresses can contain YAML special characters like '<' and '>'. To avoid YAML parsing issues, addresses that contain such characters should be enclosed in single quotes.
 
 ## Troubleshooting
 

action.yml

@@ -73,5 +73,5 @@ inputs:
     description: Custom envelope recipient addresses for SMTP RCPT TO command (separated with comma)
     required: false
 runs:
-  using: node20
+  using: node24
   main: main.js

main.js

@@ -1,4 +1,5 @@
 import nodemailer from "nodemailer";
+import addressparser from "nodemailer/lib/addressparser/index.js";
 import * as core from "@actions/core";
 import * as glob from "@actions/glob";
 import fs from "node:fs";
@@ -39,6 +40,39 @@ function sleep(ms) {
     });
 }
 
+/**
+ * Prepare an envelope object for nodemailer.
+ *
+ * If only one of envelopeFrom or envelopeTo is set, make sure that both
+ * are set in the returned object. Furthermore, make sure that the attribute 'to'
+ * is an array of email addresses, not a comma-separated string.
+ */
+function setupEnvelope(envelopeFrom, envelopeTo, from, to, cc, bcc) {
+    if (envelopeFrom || envelopeTo) {
+        // Take address in from, if envelopeFrom is not set.
+        envelopeFrom = envelopeFrom ? addressparser(envelopeFrom) : addressparser(from);
+        if (envelopeFrom.length != 1 || envelopeFrom[0].address == '') {
+            throw new Error("'envelopeFrom' address is invalid");
+        }
+        if (envelopeTo) {
+            envelopeTo = addressparser(envelopeTo);
+        } else {
+            // Take addresses in to, cc and bcc. Deduplication is handled by nodemailer.
+            for (const src of [to, cc, bcc]) {
+                if (src) {
+                    let parsed = addressparser(src);
+                    envelopeTo = envelopeTo ? envelopeTo.concat(parsed) : parsed;
+                }
+            }
+        }
+        return {
+            from: envelopeFrom,
+            to: envelopeTo,
+        };
+    }
+    return undefined;
+}
+
 async function main() {
     try {
         let serverAddress = core.getInput("server_address");
@@ -111,7 +145,8 @@ async function main() {
 
         // Basic check for an email sender address
         // Either: "Plain Simple Name <user@doma.in>" or just "user@doma.in" (without the <>)
-        if (!(/^([^<>@\s]+\s+)+<[^@\s>]+@[^@\s>]+>$/.test(from) || /^[^<>@\s]+@[^@\s<>]+$/.test(from))) {
+        let parsed = addressparser(from);
+        if (parsed.length != 1 || parsed[0].address == '') {
             throw new Error("'from' address is invalid");
         }
 
@@ -148,10 +183,7 @@ async function main() {
             proxy: process.env.HTTP_PROXY,
         });
 
-        let i = 1;
-        while (true) {
-            try {
-                const info = await transport.sendMail({
+        const messageOptions = {
             from: from,
             to: to,
             subject: getText(subject, false),
@@ -169,14 +201,13 @@ async function main() {
             attachments: attachments
                 ? await getAttachments(attachments)
                 : undefined,
-                    envelope:
-                        envelopeFrom || envelopeTo
-                            ? {
-                                  from: envelopeFrom ? envelopeFrom : undefined,
-                                  to: envelopeTo ? envelopeTo : undefined,
-                              }
-                            : undefined,
-                });
+            envelope: setupEnvelope(envelopeFrom, envelopeTo, from, to, cc, bcc),
+        };
+
+        let i = 1;
+        while (true) {
+            try {
+                const info = await transport.sendMail(messageOptions);
                 break;
             } catch (error) {
                 if (!error.message.includes("Try again later,")) {