feat(loader): Add boilerplate for js sdk dynamic loader

src/sentry/conf/server.py

@@ -2530,6 +2530,7 @@ def build_cdc_postgres_init_db_volume(settings):
 # - 'https://browser.sentry-cdn.com/6.19.7/bundle.min.js' will stay the same.
 JS_SDK_LOADER_DEFAULT_SDK_URL = ""
 
+
 # block domains which are generally used by spammers -- keep this configurable
 # in case a self-hosted install wants to allow it
 INVALID_EMAIL_ADDRESS_PATTERN = re.compile(r"\@qq\.com$", re.I)

src/sentry/web/frontend/js_sdk_dynamic_loader.py

@@ -0,0 +1,69 @@
+from typing import Optional, Tuple, TypedDict
+
+from rest_framework.request import Request
+from rest_framework.response import Response
+
+from sentry.loader.browsersdkversion import get_browser_sdk_version
+from sentry.models import Project, ProjectKey
+from sentry.web.frontend.base import BaseView
+
+
+class SdkConfig(TypedDict):
+    dsn: str
+
+
+class LoaderContext(TypedDict):
+    config: SdkConfig
+    jsSdkUrl: Optional[str]
+    publicKey: Optional[str]
+
+
+class JavaScriptSdkDynamicLoader(BaseView):
+    auth_required = False
+
+    # Do not let an organization load trigger session, breaking Vary header.
+    # TODO: This view should probably not be a subclass of BaseView if it doesn't actually use the
+    # large amount of organization related support utilities, but that ends up being a large refactor.
+    def determine_active_organization(self, request: Request, organization_slug=None) -> None:
+        pass
+
+    def _get_bundle_kind_modifier(self) -> str:
+        """Returns a string that is used to modify the bundle name"""
+        bundle_kind_modifier = ""
+
+        # if tracing
+        bundle_kind_modifier += ".tracing"
+
+        # if replay
+        bundle_kind_modifier += ".replay"
+
+        # if es5
+        bundle_kind_modifier += ".es5"
+
+        # if debug
+        bundle_kind_modifier += ".debug"
+
+        return bundle_kind_modifier
+
+    def _get_context(self, key: str) -> Tuple[LoaderContext, Optional[str], Optional[str]]:
+        """Sets context information needed to render the loader"""
+        if not key:
+            return ({}, None, None)
+
+        sdk_version = get_browser_sdk_version(key)
+
+        # TODO(abhi): Right now this loader only supports returning es6 JS bundles.
+        # We may want to re-evaluate this.
+
+        return ({}, sdk_version, None)
+
+    def get(self, request: Request, public_key: str, minified: str) -> Response:
+        """Returns a JS file that dynamically loads the SDK based on project settings"""
+        key = None
+
+        try:
+            key = ProjectKey.objects.get_from_cache(public_key=public_key)
+        except ProjectKey.DoesNotExist:
+            pass
+        else:
+            key.project = Project.objects.get_from_cache(id=key.project_id)

src/sentry/web/urls.py

@@ -23,6 +23,7 @@
 from sentry.web.frontend.group_tag_export import GroupTagExportView
 from sentry.web.frontend.home import HomeView
 from sentry.web.frontend.idp_email_verification import AccountConfirmationView
+from sentry.web.frontend.js_sdk_dynamic_loader import JavaScriptSdkDynamicLoader
 from sentry.web.frontend.js_sdk_loader import JavaScriptSdkLoader
 from sentry.web.frontend.mailgun_inbound_webhook import MailgunInboundWebhookView
 from sentry.web.frontend.newest_performance_issue import NewestPerformanceIssueView
@@ -116,6 +117,12 @@
         JavaScriptSdkLoader.as_view(),
         name="sentry-js-sdk-loader",
     ),
+    # Javascript SDK Loader
+    url(
+        r"^js-sdk-loader/(?P<public_key>[^/\.]+)(?:(?P<minified>\.min))?\.js$",
+        JavaScriptSdkDynamicLoader.as_view(),
+        name="sentry-js-sdk-loader",
+    ),
     # Versioned API
     url(r"^api/0/", include("sentry.api.urls")),
     # Legacy unversioned endpoints

tests/sentry/web/frontend/test_js_sdk_dynamic_loader.py

@@ -0,0 +1,31 @@
+import pytest
+from django.conf import settings
+
+from sentry.testutils import TestCase
+
+
+class JavaScriptSdkDynamicLoaderTest(TestCase):
+    @pytest.fixture(autouse=True)
+    def set_settings(self):
+        settings.JS_SDK_LOADER_SDK_VERSION = "7.36.0"
+        settings.JS_SDK_LOADER_DEFAULT_SDK_URL = "https://browser.sentry-cdn.com/%s/bundle%s.min.js"
+
+    def test_noop_no_pub_key(self):
+        # When given no public key, respond with the noop template
+        pass
+
+    def test_noop(self):
+        # When given a public key, but no default SDK URL, respond with the noop template
+        pass
+
+    def test_no_replace(self):
+        # When given a public key, and a default SDK URL, but the SDK version is not set, respond with the noop template
+        pass
+
+    def test_renders_js_loader(self):
+        # When given a public key, and a default SDK URL, and the SDK version is set, respond with the js loader template
+        pass
+
+    def test_minified(self):
+        # When given a public key, and a default SDK URL, and the SDK version is set, respond with the minified js loader template
+        pass