feat: support favoriting topics

src/api/folderResourceMetaApi.ts

@@ -12,11 +12,12 @@ import { IAudioMetaInformation } from "@ndla/types-backend/audio-api";
 import { IImageMetaInformationV2 } from "@ndla/types-backend/image-api";
 import { ILearningPathSummaryV2 } from "@ndla/types-backend/learningpath-api";
 import { Node } from "@ndla/types-taxonomy";
+import { fetchArticles } from "./articleApi";
 import { fetchAudio } from "./audioApi";
 import { searchConcepts } from "./conceptApi";
 import { fetchFolder } from "./folderApi";
 import { fetchImage } from "./imageApi";
-import { searchNodes } from "./taxonomyApi";
+import { queryNodes, searchNodes } from "./taxonomyApi";
 import { fetchVideo } from "./videoApi";
 import { defaultLanguage } from "../config";
 import {
@@ -28,8 +29,18 @@ import {
   GQLQueryFolderResourceMetaSearchArgs,
 } from "../types/schema";
 import { articleToMeta, learningpathToMeta } from "../utils/apiHelpers";
+import { getArticleIdFromUrn } from "../utils/articleHelpers";
 
-type MetaType = "article" | "learningpath" | "multidisciplinary" | "concept" | "image" | "audio" | "video" | "folder";
+type MetaType =
+  | "article"
+  | "learningpath"
+  | "multidisciplinary"
+  | "concept"
+  | "image"
+  | "audio"
+  | "video"
+  | "folder"
+  | "topic";
 
 const findResourceTypes = (result: Node | undefined, context: ContextWithLoaders): GQLFolderResourceResourceType[] => {
   const ctx = result?.contexts?.[0];
@@ -101,6 +112,9 @@ export const fetchFolderResourceMeta = async (
   } else if (resource.resourceType === "multidisciplinary") {
     const res = await fetchAndTransformResourceMeta([resource], context, "multidisciplinary");
     return res[0] ?? null;
+  } else if (resource.resourceType === "topic") {
+    const res = await fetchTopicMeta([resource], context, "topic");
+    return res[0] ?? null;
   } else if (resource.resourceType === "image") {
     const res = await fetchImageMeta([resource], context, "image");
     return res[0] ?? null;
@@ -120,6 +134,34 @@ export const fetchFolderResourceMeta = async (
   throw Error(`Resource type '${resource.resourceType}' not supported`);
 };
 
+export const fetchTopicMeta = async (
+  resources: GQLFolderResourceMetaSearchInput[] | undefined,
+  context: ContextWithLoaders,
+  type: MetaType,
+): Promise<GQLFolderResourceMeta[]> => {
+  if (!resources?.length) return [];
+  const ids = resources.map((r) => r.id);
+  const topics = await queryNodes({ ids, language: context.language, nodeType: "TOPIC" }, context);
+
+  const articles = await fetchArticles(
+    topics.map((t) => (t.contentUri ? getArticleIdFromUrn(t.contentUri) : undefined)).filter((t): t is string => !!t),
+    context,
+  );
+
+  return ids.map((id) => {
+    const node = topics.find((t) => t.id === id);
+    const article = articles.find((a) => a?.id.toString() === getArticleIdFromUrn(node?.contentUri ?? ""));
+    return {
+      id,
+      title: article?.title.title ?? node?.name ?? "",
+      type: type.toUpperCase(),
+      description: article?.metaDescription.metaDescription ?? "",
+      metaImage: article?.metaImage,
+      resourceTypes: findResourceTypes(node, context),
+    };
+  });
+};
+
 export const fetchFolderMeta = async (
   resources: GQLFolderResourceMetaSearchInput[] | undefined,
   context: ContextWithLoaders,