send_custom_email: Add a flag for sending release announcements.

templates/zerver/emails/custom_email_base.pre.html

@@ -13,9 +13,13 @@
 
 {% block manage_preferences %}
     {% if remote_server_email %}
-    <p>You are receiving this email to update you about important changes to Zulip's Terms of Service.</p>
-    <a href="{{ unsubscribe_link }}">Unsubscribe</a>
+        {% if released_version %}
+        <p>You are receiving this email because you opted into release notifications.</p>
+        {% else %}
+        <p>You are receiving this email to update you about important changes to Zulip's Terms of Service.</p>
+        <a href="{{ unsubscribe_link }}">Unsubscribe</a>
+        {% endif %}
     {% elif unsubscribe_link %}
-    <p><a href="{{ realm_url }}/#settings/notifications">{{ _("Manage email preferences") }}</a> | <a href="{{ unsubscribe_link }}">{{ _("Unsubscribe from marketing emails") }}</a></p>
+        <p><a href="{{ realm_url }}/#settings/notifications">{{ _("Manage email preferences") }}</a> | <a href="{{ unsubscribe_link }}">{{ _("Unsubscribe from marketing emails") }}</a></p>
     {% endif %}
 {% endblock %}

templates/zerver/emails/custom_email_base.pre.manage_preferences_block.txt

@@ -1,9 +1,13 @@
 
 ---
 {% if remote_server_email %}
+{% if released_version %}
+You are receiving this email because you opted into release notifications.
+{% else %}
 You are receiving this email to update you about important changes to Zulip's Terms of Service.
 
 Unsubscribe: {{ unsubscribe_link }}
+{% endif %}
 {% elif unsubscribe_link %}
 {{ _("Manage email preferences") }}:
 

zerver/management/commands/send_custom_email.py

@@ -9,11 +9,12 @@ from typing_extensions import override
 
 from confirmation.models import one_click_unsubscribe_link
 from zerver.lib.management import ZulipBaseCommand
-from zerver.lib.send_email import send_custom_email, send_custom_server_email
+from zerver.lib.send_email import custom_email_sender, send_custom_email, send_custom_server_email
 from zerver.models import Realm, UserProfile
 
 if settings.ZILENCER_ENABLED:
-    from zilencer.models import RemoteZulipServer
+    from corporate.lib.stripe import BILLING_SUPPORT_EMAIL
+    from zilencer.models import RemoteRealmBillingUser, RemoteServerBillingUser, RemoteZulipServer
 
 
 class Command(ZulipBaseCommand):
@@ -41,6 +42,11 @@ class Command(ZulipBaseCommand):
             action="store_true",
             help="Send to registered contact email addresses for remote Zulip servers.",
         )
+        targets.add_argument(
+            "--announce-release",
+            metavar="VERSION",
+            help="Announce a major or minor release to remote servers.",
+        )
         targets.add_argument(
             "--all-sponsored-org-admins",
             action="store_true",
@@ -133,6 +139,45 @@ class Command(ZulipBaseCommand):
                 for server in servers:
                     print(f"  {server.contact_email} ({server.hostname})")
             return
+        elif options["announce_release"]:
+            server_users = RemoteServerBillingUser.objects.filter(
+                is_active=True,
+                remote_server__deactivated=False,
+            )
+            realm_users = RemoteRealmBillingUser.objects.filter(
+                is_active=True,
+                remote_realm__server__deactivated=False,
+                remote_realm__is_system_bot_realm=False,
+                remote_realm__registration_deactivated=False,
+                remote_realm__realm_deactivated=False,
+                remote_realm__realm_locally_deleted=False,
+            )
+            if options["announce_release"].endswith(".0"):
+                server_users = server_users.filter(enable_major_release_emails=True)
+                realm_users = realm_users.filter(enable_major_release_emails=True)
+            else:
+                server_users = server_users.filter(enable_maintenance_release_emails=True)
+                realm_users = realm_users.filter(enable_maintenance_release_emails=True)
+            # This does an implicit "distinct"
+            all_emails = server_users.union(realm_users).values_list("email", flat=True)
+            del options["from_address"]
+            email_sender = custom_email_sender(
+                dry_run=dry_run, from_address=BILLING_SUPPORT_EMAIL, **options
+            )
+
+            for email in all_emails:
+                email_sender(
+                    to_email=email,
+                    context={
+                        "remote_server_email": True,
+                        "released_version": options["announce_release"],
+                    },
+                )
+            if dry_run:
+                print("Would send the above email to:")
+                for email in all_emails:
+                    print(f"  {email}")
+            return
 
         if options["entire_server"]:
             users = UserProfile.objects.filter(