♻️ Create backend package (#643)

packages/backend/trpc/routers/whoami.ts

@@ -0,0 +1,27 @@
+import { prisma } from "@rallly/database";
+
+import { publicProcedure, router } from "../trpc";
+import { UserSession } from "../types";
+
+export const whoami = router({
+  get: publicProcedure.query(async ({ ctx }): Promise<UserSession> => {
+    if (ctx.user.isGuest) {
+      return { isGuest: true, id: ctx.user.id };
+    }
+
+    const user = await prisma.user.findUnique({
+      select: { id: true, name: true, email: true },
+      where: { id: ctx.user.id },
+    });
+
+    if (user === null) {
+      ctx.session.destroy();
+      throw new Error("User not found");
+    }
+
+    return { isGuest: false, ...user };
+  }),
+  destroy: publicProcedure.mutation(async ({ ctx }) => {
+    ctx.session.destroy();
+  }),
+});