improve graphql error handling

web/src/app/aktuelt/[slug]/page.tsx

@@ -30,11 +30,16 @@ export async function generateStaticParams() {
   `);
   const { data, error } = await getClient().query(allNewsSlugsQuery, {});
 
-  if (data === undefined || error) {
-    throw new Error("failed to generate static params");
+  if (error) {
+    throw new Error(error.message);
+  }
+  if (!data?.pages) {
+    throw new Error(
+      "Failed to generate static params for subpages of /aktuelt"
+    );
   }
 
-  return data?.pages.map((page: any) => ({
+  return data.pages.map((page: any) => ({
     slug: page.slug,
   }));
 }
@@ -46,12 +51,13 @@ export async function generateMetadata(
   const { data, error } = await getClient().query(newsBySlugQuery, {
     slug: params.slug,
   });
-  const news = (data?.news ?? []) as NewsFragment[];
-
-  if (!news) {
+  if (error) {
+    throw new Error(error.message);
+  }
+  if (!data?.news) {
     return null;
   }
-
+  const news = data.news as NewsFragment;
   const metadata = await getSeoMetadata(news, parent);
   return metadata;
 }
@@ -61,13 +67,15 @@ export default async function Page({ params }: { params: { slug: string } }) {
     slug: params.slug,
   });
 
-  if (data?.news === null || error) {
+  if (error) {
+    throw new Error(error.message);
+  }
+  if (!data?.news) {
     return notFound();
   }
 
-  const news = (data?.news ?? {}) as NewsFragment;
+  const news = data?.news as NewsFragment;
   const featuredImage: any = news.featuredImage;
-
   return (
     <main className="site-main" id="main">
       <section className="news-header">