content-sdk-loaders

Loaders (no Angular DI)

Code under src/content-sdk/ runs in two contexts: the Angular SSR resolver, and the plain Express POST /_data middleware where no Angular injector exists. That is why loaders live here and not in src/app/.

• Never use inject(), constructor injection, or Angular services in a loader body or anywhere under src/content-sdk/
• Config and client come from static imports: scConfig from sitecore.config.ts, getClient() from src/content-sdk/client/sitecore-client.ts
• scConfig is read-only here. Changing a config value means editing sitecore.config.ts and passing it in the first argument of defineConfig — not assigning to scConfig and not inlining a literal in the loader
• Request state comes from the LoaderContext argument: getLanguage, getSiteName, getVariantId, getComponentVariantIds, getEditingPreviewData, splitLocaleFromPath
• One LOADERS object feeds both provideLoaderRegistry(LOADERS) (app.config.ts) and createLoaderDataServiceMiddleware(config, { loaders: LOADERS, cache }) (server.ts) — no separate server loader set
• Registry key must match the loaderResolver('<key>') argument in app.routes.ts
• Return JSON-serializable data — results cross TransferState and the /_data HTTP boundary
• Not found → throw new NotFoundNavigationError(); redirects are never cached
• unstorage, express, node:* and every create*Middleware are server-only — keep them out of anything reachable from src/main.ts

Depth: .agents/docs/AGENTS-loaders-and-di.md · skill: content-sdk-loader-authoring