feat: add embedded dashboard E2E tests to Playwright CI (#39300)

Co-authored-by: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

docker/pythonpath_dev/superset_config_docker_light.py

@@ -18,6 +18,8 @@
 # Configuration for docker-compose-light.yml - disables Redis and uses minimal services
 
 # Import all settings from the main config first
+import os
+
 from flask_caching.backends.filesystemcache import FileSystemCache
 
 from superset_config import *  # noqa: F403
@@ -36,3 +38,32 @@ THUMBNAIL_CACHE_CONFIG = CACHE_CONFIG
 
 # Disable Celery entirely for lightweight mode
 CELERY_CONFIG = None  # type: ignore[assignment,misc]
+
+# Honor SUPERSET_FEATURE_<NAME> env vars on top of any flags inherited from
+# superset_config. Lets local dev/e2e enable features (e.g. EMBEDDED_SUPERSET)
+# without editing shipped config files. Only the literal string "true"
+# (case-insensitive) is treated as enabled — "1"/"yes"/"on" are not, matching
+# the strict-string convention used elsewhere in Superset's env parsing.
+FEATURE_FLAGS = {
+    **FEATURE_FLAGS,  # noqa: F405
+    **{
+        name[len("SUPERSET_FEATURE_") :]: value.strip().lower() == "true"
+        for name, value in os.environ.items()
+        if name.startswith("SUPERSET_FEATURE_")
+    },
+}
+
+if os.environ.get("SUPERSET_FEATURE_EMBEDDED_SUPERSET", "").strip().lower() == "true":
+    # Disable Talisman so /embedded/<uuid> doesn't return X-Frame-Options:SAMEORIGIN.
+    # Without this, browsers refuse to render Superset inside an iframe from a
+    # different origin (i.e. the embedded SDK use case). Production/CI configures
+    # Talisman with explicit `frame-ancestors`; for the lightweight local stack we
+    # just turn it off.
+    TALISMAN_ENABLED = False
+
+    # Guest tokens (used by the embedded SDK) inherit the "Public" role's perms.
+    # Out of the box Public has zero perms, so embedded dashboards immediately fail
+    # their first call (`/api/v1/me/roles/`) with 403. Mirror Public to Gamma —
+    # the standard read-only viewer role — so the embedded flow can authenticate
+    # and load dashboard data in local dev.
+    PUBLIC_ROLE_LIKE = "Gamma"