fix: extra fetch to get storage description

solid-common-lib/src/index.ts

@@ -1,4 +1,4 @@
-import { getPodUrlAll, getSolidDataset, getStringNoLocale, getStringWithLocale, getThing, getUrl } from "@inrupt/solid-client";
+import { getPodUrlAll, getSolidDataset, getStringNoLocale, getStringWithLocale, getThing, getThingAll, getUrl } from "@inrupt/solid-client";
 import { Session } from "@inrupt/solid-client-authn-browser";
 import { url } from "./types";
 import { FOAF } from "@inrupt/vocab-common-rdf";
@@ -11,65 +11,94 @@ export { url } from "./types";
  * @returns The URL's to the pods the user has access to
  */
 export async function listPodUrls(session: Session): Promise<url[]> {
-    const urls = await getPodUrlAll(session.info.webId!, {
-        fetch: session.fetch,
-    });
-    if (urls.length === 0) {
-        // TODO this is a guess and should be much more resilient
-        urls.push((new URL('../', session.info.webId!)).toString())
-    }
-    return urls;
+  const webId = session.info.webId!
+  const urls = await getPodUrlAll(webId, {
+    fetch: session.fetch,
+  });
+
+  const fetchedUrl = await fetchStorageTriple(webId);
+  console.log(fetchedUrl)
+  if (fetchedUrl) {
+    urls.push(fetchedUrl)
+  }
+
+  if (urls.length === 0) {
+    urls.push((new URL('../', webId)).toString())
+  }
+  return urls;
 }
 
+/**
+  * Get the storage description following the solid specification (only if the webid is hosted on the pod)
+  */
+async function fetchStorageTriple(webId: string) {
+  const resp = await fetch(webId, {
+    // If cache is used some links headers are not passed
+    cache: "no-cache"
+  });
+  if (!resp.ok) {
+    throw new Error("Failed to make HEAD request to webId")
+  }
+  const links = resp.headers.get("link")?.split(", ")
+  const storageDescriptionUrl = links?.find(l => l.includes('rel="http://www.w3.org/ns/solid/terms#storageDescription"'))?.replace(/<([^>]+)>.*/, "$1")
+  if (!storageDescriptionUrl) {
+    throw new Error("No storage description found in the web id")
+  }
+
+  const dataset = await getSolidDataset(storageDescriptionUrl)
+  const things = getThingAll(dataset);
+  const storageThing = things.find(t => t.predicates["http://www.w3.org/1999/02/22-rdf-syntax-ns#type"].namedNodes?.includes("http://www.w3.org/ns/pim/space#Storage"));
+  return storageThing?.url
+}
 
 /**
  * @param session An active Solid client connection
  * @param url URL to the user's pod
  * @returns the information about the user
  */
 export async function getProfileInfo(
-    session: Session,
-    url: url
+  session: Session,
+  url: url
 ): Promise<{
-    name: string;
-    mbox: string;
-    description: string;
-    img: string;
-    phone: string;
+  name: string;
+  mbox: string;
+  description: string;
+  img: string;
+  phone: string;
 }> {
-    const dataset = await getSolidDataset(`${url}/profile/card#me`, {
-        fetch: session.fetch,
-    });
-    const profileThing = getThing(dataset, `${url}/profile/card#me`);
+  const dataset = await getSolidDataset(`${url}/profile/card#me`, {
+    fetch: session.fetch,
+  });
+  const profileThing = getThing(dataset, `${url}/profile/card#me`);
 
-    if (!profileThing) {
-        throw new Error("Profile information not found");
-    }
+  if (!profileThing) {
+    throw new Error("Profile information not found");
+  }
 
-    const name = getStringNoLocale(profileThing, Schema.name) ?? "";
-    const mbox = getUrl(profileThing, Schema.mbox) ?? "";
-    const description =
-        getStringWithLocale(profileThing, Schema.description, "en-us") ?? "";
-    const img = getUrl(profileThing, Schema.img) ?? "";
-    const phone = getUrl(profileThing, Schema.phone) ?? "";
+  const name = getStringNoLocale(profileThing, Schema.name) ?? "";
+  const mbox = getUrl(profileThing, Schema.mbox) ?? "";
+  const description =
+    getStringWithLocale(profileThing, Schema.description, "en-us") ?? "";
+  const img = getUrl(profileThing, Schema.img) ?? "";
+  const phone = getUrl(profileThing, Schema.phone) ?? "";
 
-    return { name, mbox, description, img, phone };
+  return { name, mbox, description, img, phone };
 }
 
 export const Schema = {
-    name: FOAF.name,
-    mbox: FOAF.mbox,
-    description: "http://schema.org/description",
-    img: FOAF.img,
-    phone: FOAF.phone,
+  name: FOAF.name,
+  mbox: FOAF.mbox,
+  description: "http://schema.org/description",
+  img: FOAF.img,
+  phone: FOAF.phone,
 
-    text: "https://schema.org/text",
-    video: "https://schema.org/video",
-    image: "https://schema.org/image",
+  text: "https://schema.org/text",
+  video: "https://schema.org/video",
+  image: "https://schema.org/image",
 
-    additionalType: "https://schema.org/additionalType",
-    location: "https://schema.org/location",
-    provider: "https://schema.org/provider",
-    scheduledTime: "https://schema.org/scheduledTime",
+  additionalType: "https://schema.org/additionalType",
+  location: "https://schema.org/location",
+  provider: "https://schema.org/provider",
+  scheduledTime: "https://schema.org/scheduledTime",
 };