Replacing URLs by user ids in origins

src/lib/user-id.ts

@@ -0,0 +1,36 @@
+export const userId = (params: { username: string; database: string }) => {
+  const { username, database } = params;
+  const dbUrl = new URL(database);
+  return `@${username}>${dbUrl.hostname}`;
+};
+
+export const parseUserId = (id: string) => {
+  const matches = id.match(/^@([^>]+)>(.+)$/);
+  if (!matches) {
+    return null;
+  }
+  return { username: matches[1], database: matches[2] };
+};
+
+function hex2a(hex: string) {
+  var str = '';
+  for (var i = 0; i < hex.length; i += 2) {
+    var v = parseInt(hex.substr(i, 2), 16);
+    if (v) str += String.fromCharCode(v);
+  }
+  return str;
+}
+
+export const parseDbUrl = (urlString: string) => {
+  origin;
+  const url = new URL(urlString);
+  const match = url.pathname.match(/\/userdb-(.*)\//);
+  if (!match || match.length < 2) {
+    return { username: '', database: url.hostname };
+  }
+  const [_, encodedUser] = match;
+  return { username: hex2a(encodedUser), database: urlString };
+};
+
+export const dbUrlToUserId = (urlString: string) =>
+  userId(parseDbUrl(urlString));