Chapter 15 - implement authentication

app/lib/actions.ts

@@ -4,6 +4,9 @@ import { z } from 'zod';
 import { sql } from '@vercel/postgres';
 import { revalidatePath } from 'next/cache';
 import {redirect} from "next/navigation";
+import { signIn } from '@/auth';
+import { AuthError } from 'next-auth';
+
 
 const FormSchema = z.object({
     id: z.string(),
@@ -97,4 +100,23 @@ export async function deleteInvoice(id: string) {
     } catch (error) {
         return { message: 'Database Error: Failed to Delete Invoice.' };
     }
+}
+
+export async function authenticate(
+    prevState: string | undefined,
+    formData: FormData,
+) {
+    try {
+        await signIn('credentials', formData);
+    } catch (error) {
+        if (error instanceof AuthError) {
+            switch (error.type) {
+                case 'CredentialsSignin':
+                    return 'Invalid credentials.';
+                default:
+                    return 'Something went wrong.';
+            }
+        }
+        throw error;
+    }
 }

app/login/page.tsx

@@ -0,0 +1,17 @@
+import AcmeLogo from '@/app/ui/acme-logo';
+import LoginForm from '@/app/ui/login-form';
+
+export default function LoginPage() {
+    return (
+        <main className="flex items-center justify-center md:h-screen">
+            <div className="relative mx-auto flex w-full max-w-[400px] flex-col space-y-2.5 p-4 md:-mt-32">
+                <div className="flex h-20 w-full items-end rounded-lg bg-blue-500 p-3 md:h-36">
+                    <div className="w-32 text-white md:w-36">
+                        <AcmeLogo />
+                    </div>
+                </div>
+                <LoginForm />
+            </div>
+        </main>
+    );
+}

app/ui/dashboard/sidenav.tsx

@@ -2,6 +2,7 @@ import Link from 'next/link';
 import NavLinks from '@/app/ui/dashboard/nav-links';
 import AcmeLogo from '@/app/ui/acme-logo';
 import { PowerIcon } from '@heroicons/react/24/outline';
+import { signOut } from '@/auth';
 
 export default function SideNav() {
   return (
@@ -17,7 +18,10 @@ export default function SideNav() {
       <div className="flex grow flex-row justify-between space-x-2 md:flex-col md:space-x-0 md:space-y-2">
         <NavLinks />
         <div className="hidden h-auto w-full grow rounded-md bg-gray-50 md:block"></div>
-        <form>
+        <form action={async () => {
+            'use server';
+            await signOut();
+        }}>
           <button className="flex h-[48px] w-full grow items-center justify-center gap-2 rounded-md bg-gray-50 p-3 text-sm font-medium hover:bg-sky-100 hover:text-blue-600 md:flex-none md:justify-start md:p-2 md:px-3">
             <PowerIcon className="w-6" />
             <div className="hidden md:block">Sign Out</div>

app/ui/login-form.tsx

@@ -1,3 +1,4 @@
+'use client';
 import { lusitana } from '@/app/ui/fonts';
 import {
   AtSymbolIcon,
@@ -6,68 +7,84 @@ import {
 } from '@heroicons/react/24/outline';
 import { ArrowRightIcon } from '@heroicons/react/20/solid';
 import { Button } from './button';
+import { useFormState, useFormStatus } from 'react-dom';
+import { authenticate } from '@/app/lib/actions';
 
 export default function LoginForm() {
+  const [errorMessage, dispatch] = useFormState(authenticate, undefined);
+
   return (
-    <form className="space-y-3">
+      <form action={dispatch} className="space-y-3">
-      <div className="flex-1 rounded-lg bg-gray-50 px-6 pb-4 pt-8">
+        <div className="flex-1 rounded-lg bg-gray-50 px-6 pb-4 pt-8">
-        <h1 className={`${lusitana.className} mb-3 text-2xl`}>
+          <h1 className={`${lusitana.className} mb-3 text-2xl`}>
-          Please log in to continue.
+            Please log in to continue.
-        </h1>
+          </h1>
-        <div className="w-full">
+          <div className="w-full">
-          <div>
+            <div>
-            <label
+              <label
-              className="mb-3 mt-5 block text-xs font-medium text-gray-900"
+                  className="mb-3 mt-5 block text-xs font-medium text-gray-900"
-              htmlFor="email"
+                  htmlFor="email"
-            >
+              >
-              Email
+                Email
-            </label>
+              </label>
-            <div className="relative">
+              <div className="relative">
-              <input
+                <input
-                className="peer block w-full rounded-md border border-gray-200 py-[9px] pl-10 text-sm outline-2 placeholder:text-gray-500"
+                    className="peer block w-full rounded-md border border-gray-200 py-[9px] pl-10 text-sm outline-2 placeholder:text-gray-500"
-                id="email"
+                    id="email"
-                type="email"
+                    type="email"
-                name="email"
+                    name="email"
-                placeholder="Enter your email address"
+                    placeholder="Enter your email address"
-                required
+                    required
-              />
+                />
-              <AtSymbolIcon className="pointer-events-none absolute left-3 top-1/2 h-[18px] w-[18px] -translate-y-1/2 text-gray-500 peer-focus:text-gray-900" />
+                <AtSymbolIcon
+                    className="pointer-events-none absolute left-3 top-1/2 h-[18px] w-[18px] -translate-y-1/2 text-gray-500 peer-focus:text-gray-900"/>
+              </div>
+            </div>
+            <div className="mt-4">
+              <label
+                  className="mb-3 mt-5 block text-xs font-medium text-gray-900"
+                  htmlFor="password"
+              >
+                Password
+              </label>
+              <div className="relative">
+                <input
+                    className="peer block w-full rounded-md border border-gray-200 py-[9px] pl-10 text-sm outline-2 placeholder:text-gray-500"
+                    id="password"
+                    type="password"
+                    name="password"
+                    placeholder="Enter password"
+                    required
+                    minLength={6}
+                />
+                <KeyIcon
+                    className="pointer-events-none absolute left-3 top-1/2 h-[18px] w-[18px] -translate-y-1/2 text-gray-500 peer-focus:text-gray-900"/>
+              </div>
             </div>
           </div>
-          <div className="mt-4">
+          <LoginButton/>
-            <label
+          <div
-              className="mb-3 mt-5 block text-xs font-medium text-gray-900"
+              className="flex h-8 items-end space-x-1"
-              htmlFor="password"
+              aria-live="polite"
-            >
+              aria-atomic="true"
-              Password
+          >
-            </label>
+            {errorMessage && (
-            <div className="relative">
+                <>
-              <input
+                  <ExclamationCircleIcon className="h-5 w-5 text-red-500"/>
-                className="peer block w-full rounded-md border border-gray-200 py-[9px] pl-10 text-sm outline-2 placeholder:text-gray-500"
+                  <p className="text-sm text-red-500">{errorMessage}</p>
-                id="password"
+                </>
-                type="password"
+            )}
-                name="password"
-                placeholder="Enter password"
-                required
-                minLength={6}
-              />
-              <KeyIcon className="pointer-events-none absolute left-3 top-1/2 h-[18px] w-[18px] -translate-y-1/2 text-gray-500 peer-focus:text-gray-900" />
-            </div>
           </div>
         </div>
-        <LoginButton />
+      </form>
-        <div className="flex h-8 items-end space-x-1">
-          {/* Add form errors here */}
-        </div>
-      </div>
-    </form>
   );
 }
 
 function LoginButton() {
+  const { pending } = useFormStatus();
   return (
-    <Button className="mt-4 w-full">
+      <Button className="mt-4 w-full" aria-disabled={pending}>
-      Log in <ArrowRightIcon className="ml-auto h-5 w-5 text-gray-50" />
+        Log in <ArrowRightIcon className="ml-auto h-5 w-5 text-gray-50" />
-    </Button>
+      </Button>
   );
 }

auth.config.ts

@@ -0,0 +1,21 @@
+import type { NextAuthConfig } from 'next-auth';
+
+export const authConfig = {
+    pages: {
+        signIn: '/login',
+    },
+    callbacks: {
+        authorized({ auth, request: { nextUrl } }) {
+            const isLoggedIn = !!auth?.user;
+            const isOnDashboard = nextUrl.pathname.startsWith('/dashboard');
+            if (isOnDashboard) {
+                if (isLoggedIn) return true;
+                return false; // Redirect unauthenticated users to login page
+            } else if (isLoggedIn) {
+                return Response.redirect(new URL('/dashboard', nextUrl));
+            }
+            return true;
+        },
+    },
+    providers: [], // Add providers with an empty array for now
+} satisfies NextAuthConfig;

auth.ts

@@ -0,0 +1,40 @@
+import NextAuth from 'next-auth';
+import Credentials from 'next-auth/providers/credentials';
+import { authConfig } from './auth.config';
+import { z } from 'zod';
+import { sql } from '@vercel/postgres';
+import type { User } from '@/app/lib/definitions';
+import bcrypt from 'bcrypt';
+
+async function getUser(email: string): Promise<User | undefined> {
+    try {
+        const user = await sql<User>`SELECT * FROM users WHERE email=${email}`;
+        return user.rows[0];
+    } catch (error) {
+        console.error('Failed to fetch user:', error);
+        throw new Error('Failed to fetch user.');
+    }
+}
+
+export const { auth, signIn, signOut } = NextAuth({
+    ...authConfig,
+    providers: [
+        Credentials({
+            async authorize(credentials) {
+                const parsedCredentials = z
+                    .object({ email: z.string().email(), password: z.string().min(6) })
+                    .safeParse(credentials);
+
+                if (parsedCredentials.success) {
+                    const { email, password } = parsedCredentials.data;
+                    const user = await getUser(email);
+                    if (!user) return null;
+                    const passwordsMatch = await bcrypt.compare(password, user.password);
+                    if (passwordsMatch) return user;
+                }
+                console.log('Invalid credentials');
+                return null;
+            },
+        }),
+    ],
+});

middleware.ts

@@ -0,0 +1,9 @@
+import NextAuth from 'next-auth';
+import { authConfig } from './auth.config';
+
+export default NextAuth(authConfig).auth;
+
+export const config = {
+    // https://nextjs.org/docs/app/building-your-application/routing/middleware#matcher
+    matcher: ['/((?!api|_next/static|_next/image|.*\\.png$).*)'],
+};

package-lock.json

@@ -13,6 +13,7 @@
         "bcrypt": "^5.1.1",
         "clsx": "^2.0.0",
         "next": "^14.0.2",
+        "next-auth": "^5.0.0-beta.4",
         "postcss": "8.4.31",
         "react": "18.2.0",
         "react-dom": "18.2.0",
@@ -70,6 +71,27 @@
         "node": ">=6.0.0"
       }
     },
+    "node_modules/@auth/core": {
+      "version": "0.18.4",
+      "resolved": "https://registry.npmjs.org/@auth/core/-/core-0.18.4.tgz",
+      "integrity": "sha512-GsNhsP1xE/3FoNS3dVkPjqRljLNJ4iyL2OLv3klQGNvw3bMpROFcK4lqhx7+pPHiamnVaYt2vg1xbB+lsNaevg==",
+      "dependencies": {
+        "@panva/hkdf": "^1.1.1",
+        "cookie": "0.6.0",
+        "jose": "^5.1.0",
+        "oauth4webapi": "^2.3.0",
+        "preact": "10.11.3",
+        "preact-render-to-string": "5.2.3"
+      },
+      "peerDependencies": {
+        "nodemailer": "^6.8.0"
+      },
+      "peerDependenciesMeta": {
+        "nodemailer": {
+          "optional": true
+        }
+      }
+    },
     "node_modules/@babel/code-frame": {
       "version": "7.22.13",
       "resolved": "https://registry.npmjs.org/@babel/code-frame/-/code-frame-7.22.13.tgz",
@@ -1036,6 +1058,14 @@
         "node": ">= 8"
       }
     },
+    "node_modules/@panva/hkdf": {
+      "version": "1.1.1",
+      "resolved": "https://registry.npmjs.org/@panva/hkdf/-/hkdf-1.1.1.tgz",
+      "integrity": "sha512-dhPeilub1NuIG0X5Kvhh9lH4iW3ZsHlnzwgwbOlgwQ2wG1IqFzsgHqmKPk3WzsdWAeaxKJxgM0+W433RmN45GA==",
+      "funding": {
+        "url": "https://github.com/sponsors/panva"
+      }
+    },
     "node_modules/@pkgr/utils": {
       "version": "2.4.2",
       "resolved": "https://registry.npmjs.org/@pkgr/utils/-/utils-2.4.2.tgz",
@@ -2297,6 +2327,14 @@
       "integrity": "sha512-Kvp459HrV2FEJ1CAsi1Ku+MY3kasH19TFykTz2xWmMeq6bk2NU3XXvfJ+Q61m0xktWwt+1HSYf3JZsTms3aRJg==",
       "dev": true
     },
+    "node_modules/cookie": {
+      "version": "0.6.0",
+      "resolved": "https://registry.npmjs.org/cookie/-/cookie-0.6.0.tgz",
+      "integrity": "sha512-U71cyTamuh1CRNCfpGY6to28lxvNwPG4Guz/EVjgf3Jmzv0vlDp1atT9eS5dDjMYHucpHbWns6Lwf3BKz6svdw==",
+      "engines": {
+        "node": ">= 0.6"
+      }
+    },
     "node_modules/cross-spawn": {
       "version": "7.0.3",
       "resolved": "https://registry.npmjs.org/cross-spawn/-/cross-spawn-7.0.3.tgz",
@@ -4656,6 +4694,14 @@
       "integrity": "sha512-8wb9Yw966OSxApiCt0K3yNJL8pnNeIv+OEq2YMidz4FKP6nonSRoOXc80iXY4JaN2FC11B9qsNmDsm+ZOfMROA==",
       "dev": true
     },
+    "node_modules/jose": {
+      "version": "5.2.0",
+      "resolved": "https://registry.npmjs.org/jose/-/jose-5.2.0.tgz",
+      "integrity": "sha512-oW3PCnvyrcm1HMvGTzqjxxfnEs9EoFOFWi2HsEGhlFVOXxTE3K9GKWVMFoFw06yPUqwpvEWic1BmtUZBI/tIjw==",
+      "funding": {
+        "url": "https://github.com/sponsors/panva"
+      }
+    },
     "node_modules/js-tokens": {
       "version": "4.0.0",
       "resolved": "https://registry.npmjs.org/js-tokens/-/js-tokens-4.0.0.tgz",
@@ -5057,6 +5103,24 @@
         }
       }
     },
+    "node_modules/next-auth": {
+      "version": "5.0.0-beta.4",
+      "resolved": "https://registry.npmjs.org/next-auth/-/next-auth-5.0.0-beta.4.tgz",
+      "integrity": "sha512-vgocjvwPA8gxd/zrIP/vr9lJ/HeNe+C56lPP1D3sdyenHt8KncQV6ro7q0xCsDp1fcOKx7WAWVZH5o8aMxDzgw==",
+      "dependencies": {
+        "@auth/core": "0.18.4"
+      },
+      "peerDependencies": {
+        "next": "^14",
+        "nodemailer": "^6.6.5",
+        "react": "^18.2.0"
+      },
+      "peerDependenciesMeta": {
+        "nodemailer": {
+          "optional": true
+        }
+      }
+    },
     "node_modules/node-addon-api": {
       "version": "5.1.0",
       "resolved": "https://registry.npmjs.org/node-addon-api/-/node-addon-api-5.1.0.tgz",
@@ -5185,6 +5249,14 @@
         "set-blocking": "^2.0.0"
       }
     },
+    "node_modules/oauth4webapi": {
+      "version": "2.4.1",
+      "resolved": "https://registry.npmjs.org/oauth4webapi/-/oauth4webapi-2.4.1.tgz",
+      "integrity": "sha512-qor45aeDGaGqDOizwut+Q/rZ+J6BIJvOp7U0LtHfbFhg3O7JV5lvQFDXPNqSmcUjuq/Zeq8CIII4RD0sWLOdSQ==",
+      "funding": {
+        "url": "https://github.com/sponsors/panva"
+      }
+    },
     "node_modules/object-assign": {
       "version": "4.1.1",
       "resolved": "https://registry.npmjs.org/object-assign/-/object-assign-4.1.1.tgz",
@@ -5705,6 +5777,26 @@
         "node": ">=0.10.0"
       }
     },
+    "node_modules/preact": {
+      "version": "10.11.3",
+      "resolved": "https://registry.npmjs.org/preact/-/preact-10.11.3.tgz",
+      "integrity": "sha512-eY93IVpod/zG3uMF22Unl8h9KkrcKIRs2EGar8hwLZZDU1lkjph303V9HZBwufh2s736U6VXuhD109LYqPoffg==",
+      "funding": {
+        "type": "opencollective",
+        "url": "https://opencollective.com/preact"
+      }
+    },
+    "node_modules/preact-render-to-string": {
+      "version": "5.2.3",
+      "resolved": "https://registry.npmjs.org/preact-render-to-string/-/preact-render-to-string-5.2.3.tgz",
+      "integrity": "sha512-aPDxUn5o3GhWdtJtW0svRC2SS/l8D9MAgo2+AWml+BhDImb27ALf04Q2d+AHqUUOc6RdSXFIBVa2gxzgMKgtZA==",
+      "dependencies": {
+        "pretty-format": "^3.8.0"
+      },
+      "peerDependencies": {
+        "preact": ">=10"
+      }
+    },
     "node_modules/prelude-ls": {
       "version": "1.2.1",
       "resolved": "https://registry.npmjs.org/prelude-ls/-/prelude-ls-1.2.1.tgz",
@@ -5819,6 +5911,11 @@
         }
       }
     },
+    "node_modules/pretty-format": {
+      "version": "3.8.0",
+      "resolved": "https://registry.npmjs.org/pretty-format/-/pretty-format-3.8.0.tgz",
+      "integrity": "sha512-WuxUnVtlWL1OfZFQFuqvnvs6MiAGk9UNsBostyBOB0Is9wb5uRESevA6rnl/rkksXaGX3GzZhPup5d6Vp1nFew=="
+    },
     "node_modules/prop-types": {
       "version": "15.8.1",
       "resolved": "https://registry.npmjs.org/prop-types/-/prop-types-15.8.1.tgz",

package.json

@@ -18,6 +18,7 @@
     "bcrypt": "^5.1.1",
     "clsx": "^2.0.0",
     "next": "^14.0.2",
+    "next-auth": "^5.0.0-beta.4",
     "postcss": "8.4.31",
     "react": "18.2.0",
     "react-dom": "18.2.0",