improve typings on "getting started" (#554)

pages/getting-started.tsx

@@ -1,6 +1,6 @@
 import Head from "next/head";
 import prisma from "@lib/prisma";
-import { getSession, useSession } from "next-auth/client";
+import { useSession } from "next-auth/client";
 import {
   EventTypeCreateInput,
   ScheduleCreateInput,
@@ -30,6 +30,7 @@ import { Integration } from "pages/integrations";
 import { AddCalDavIntegrationRequest } from "../lib/integrations/CalDav/components/AddCalDavIntegration";
 import classnames from "classnames";
 import { ArrowRightIcon } from "@heroicons/react/outline";
+import { getSession } from "@lib/auth";
 
 const DEFAULT_EVENT_TYPES = [
   {
@@ -610,16 +611,21 @@ export default function Onboarding(props: OnboardingProps) {
 export async function getServerSideProps(context: NextPageContext) {
   const session = await getSession(context);
 
-  let user: User = null;
   let integrations = [];
   let credentials = [];
   let eventTypes = [];
   let schedules = [];
-
-  if (session) {
-    user = await prisma.user.findFirst({
+  if (!session?.user?.id) {
+    return {
+      redirect: {
+        permanent: false,
+        destination: "/auth/login",
+      } as const,
+    };
+  }
+  const user = await prisma.user.findFirst({
     where: {
-        email: session.user.email,
+      id: session.user.id,
     },
     select: {
       id: true,
@@ -634,6 +640,9 @@ export async function getServerSideProps(context: NextPageContext) {
       completedOnboarding: true,
     },
   });
+  if (!user) {
+    throw new Error(`Signed in as ${session.user.id} but cannot be found in db`);
+  }
 
   if (user.completedOnboarding) {
     return {
@@ -712,7 +721,6 @@ export async function getServerSideProps(context: NextPageContext) {
       id: true,
     },
   });
-  }
 
   return {
     props: {