add support for previewing pages

dnscms/dnscms/settings/base.py

@@ -41,6 +41,7 @@ INSTALLED_APPS = [
     # end cms apps
     "grapple",
     "graphene_django",
+    "wagtail_headless_preview",
     "wagtail.contrib.forms",
     "wagtail.contrib.redirects",
     "wagtail.contrib.settings",
@@ -185,11 +186,22 @@ WAGTAILSEARCH_BACKENDS = {
 }
 
 # Base URL to use when referring to full URLs within the Wagtail admin backend -
-# e.g. in notification emails. Don't include '/admin' or a trailing slash
-WAGTAILADMIN_BASE_URL = "http://example.com"
+# e.g. in notification emails. Don't include '/admin' or a trailing slash.
+# Also used by wagtail-grapple to make image URLs absolute.
+WAGTAIL_BASE_URL = os.environ.get("WAGTAIL_BASE_URL", "http://127.0.0.1:8000").rstrip("/")
+WAGTAILADMIN_BASE_URL = WAGTAIL_BASE_URL
+BASE_URL = WAGTAIL_BASE_URL
 
-# Required by wagtail-grapple to make image URLs absolute
-BASE_URL = "http://example.com"
+# Public URL of the Next.js frontend. Used to direct preview iframes and to
+# redirect "View Live" clicks on the CMS host over to the headless frontend.
+FRONTEND_BASE_URL = os.environ.get("FRONTEND_BASE_URL", "http://localhost:3000").rstrip("/")
+
+WAGTAIL_HEADLESS_PREVIEW = {
+    "CLIENT_URLS": {"default": f"{FRONTEND_BASE_URL}/api/preview"},
+    "SERVE_BASE_URL": FRONTEND_BASE_URL,
+    "ENFORCE_TRAILING_SLASH": False,
+    "REDIRECT_ON_PREVIEW": False,
+}
 
 # https://docs.wagtail.org/en/latest/releases/6.4.html#data-upload-max-number-fields-update
 DATA_UPLOAD_MAX_NUMBER_FIELDS = 10_000

dnscms/dnscms/settings/dev.py

@@ -11,13 +11,6 @@ ALLOWED_HOSTS = ["*"]
 
 EMAIL_BACKEND = "django.core.mail.backends.console.EmailBackend"
 
-# Base URL to use when referring to full URLs within the Wagtail admin backend -
-# e.g. in notification emails. Don't include '/admin' or a trailing slash
-WAGTAILADMIN_BASE_URL = "http://127.0.0.1:8000"
-
-# Required by wagtail-grapple to make image URLs absolute
-BASE_URL = "http://127.0.0.1:8000"
-
 try:
     from .local import *
 except ImportError: