Build a User Management App with Next.js
This tutorial demonstrates how to build a basic user management app. The app authenticates and identifies the user, stores their profile information in the database, and allows the user to log in, update their profile details, and upload a profile photo. The app uses:
- Supabase Database - a Postgres database for storing your user data and Row Level Security so data is protected and users can only access their own information.
- Supabase Auth - users log in through magic links sent to their email (without having to set up passwords).
- Supabase Storage - users can upload a profile photo.
note
If you get stuck while working through this guide, refer to the full example on GitHub.
Project setup#
Before we start building we're going to set up our Database and API. This is as simple as starting a new Project in Supabase and then creating a "schema" inside the database.
Create a project#
- Create a new project in the Supabase Dashboard.
- Enter your project details.
- Wait for the new database to launch.
Set up the database schema#
Now we are going to set up the database schema. We can use the "User Management Starter" quickstart in the SQL Editor, or you can just copy/paste the SQL from below and run it yourself.
- Go to the SQL Editor page in the Dashboard.
- Click User Management Starter.
- Click Run.
note
You can easily pull the database schema down to your local project by running the db pull
command. Read the local development docs for detailed instructions.
_10supabase link --project-ref <project-id>_10# You can get <project-id> from your project's dashboard URL: https://supabase.com/dashboard/project/<project-id>_10supabase db pull
Get the API Keys#
Now that you've created some database tables, you are ready to insert data using the auto-generated API.
We just need to get the Project URL and anon
key from the API settings.
- Go to the API Settings page in the Dashboard.
- Find your Project
URL
,anon
, andservice_role
keys on this page.
Building the App#
Let's start building the Next.js app from scratch.
Initialize a Next.js app#
We can use create-next-app
to initialize an app called supabase-nextjs
:
_10npx create-next-app@latest --use-npm supabase-nextjs_10cd supabase-nextjs
Then install the Supabase client library: supabase-js
_10npm install @supabase/supabase-js
And finally we want to save the environment variables in a .env.local
.
All we need are the API URL and the anon
key that you copied earlier.
And one optional step is to update the CSS file app/globals.css
to make the app look nice.
You can find the full contents of this file here.
Supabase Auth Helpers#
Next.js is a highly versatile framework offering pre-rendering at build time (SSG), server-side rendering at request time (SSR), API routes, and middleware edge-functions.
It can be challenging to authenticate your users in all these different environments, that's why we've created the Supabase Auth Helpers to make user management and data fetching within Next.js as easy as possible.
Install the auth helpers for Next.js
_10npm install @supabase/auth-helpers-nextjs @supabase/supabase-js
Next.js Middleware#
Create a middleware.js
file and include the following content to:
- Verify if there is an authenticated Supabase user
- Validate if the user is authenticated and currently on the sign-in page, redirecting them to the
account
page - Verify if the user is not authenticated and currently on the account page, redirecting them to the
sign-in
page.
Set up a Login component#
Supabase Auth UI#
We can use the Supabase Auth UI a pre-built React component for authenticating users via OAuth, email, and magic links.
Install the Supabase Auth UI for React
_10npm install @supabase/auth-ui-react @supabase/auth-ui-shared
Create an AuthForm
client side component with the Auth
component rendered within it:
note
If you are using TypeScript for this project, see generating types to automatically generate types from your database tables.
Add the AuthForm
component to your home page
Proof Key for Code Exchange (PKCE)#
As we are employing Proof Key for Code Exchange (PKCE) in our authentication flow, it is necessary to create a route handler responsible for exchanging the code for a session.
In the following code snippet, we perform the following steps:
- Retrieve the code sent back from the Supabase Auth server using the
code
query parameter. - Exchange this code for a session, which we store in our chosen storage mechanism (in this case, cookies).
- Finally, we redirect the user to the
account
page.
Sign out#
Let's create a route handler to handle the signout from the server side.
Account page#
After a user is signed in we can allow them to edit their profile details and manage their account.
Let's create a new component for that called AccountForm
within the app/account
folder.
Create a account page for the AccountForm
component we just created
Launch!#
Now that we have all the pages, route handlers and components in place, let's run this in a terminal window:
_10npm run dev
And then open the browser to localhost:3000 and you should see the completed app.
Bonus: Profile photos#
Every Supabase project is configured with Storage for managing large files like photos and videos.
Create an upload widget#
Let's create an avatar widget for the user so that they can upload a profile photo. We can start by creating a new component:
Add the new widget#
And then we can add the widget to the AccountForm
component:
Storage management#
If you upload additional profile photos, they'll accumulate
in the avatars
bucket because of their random names with only the latest being referenced
from public.profiles
and the older versions getting orphaned.
To automatically remove obsolete storage objects, extend the database
triggers. Note that it is not sufficient to delete the objects from the
storage.objects
table because that would orphan and leak the actual storage objects in
the S3 backend. Instead, invoke the storage API within Postgres via the http
extension.
Enable the http extension for the extensions
schema in the Dashboard.
Then, define the following SQL functions in the SQL Editor to delete
storage objects via the API:
_34create or replace function delete_storage_object(bucket text, object text, out status int, out content text)_34returns record_34language 'plpgsql'_34security definer_34as $$_34declare_34 project_url text := '<YOURPROJECTURL>';_34 service_role_key text := '<YOURSERVICEROLEKEY>'; -- full access needed_34 url text := project_url||'/storage/v1/object/'||bucket||'/'||object;_34begin_34 select_34 into status, content_34 result.status::int, result.content::text_34 FROM extensions.http((_34 'DELETE',_34 url,_34 ARRAY[extensions.http_header('authorization','Bearer '||service_role_key)],_34 NULL,_34 NULL)::extensions.http_request) as result;_34end;_34$$;_34_34create or replace function delete_avatar(avatar_url text, out status int, out content text)_34returns record_34language 'plpgsql'_34security definer_34as $$_34begin_34 select_34 into status, content_34 result.status, result.content_34 from public.delete_storage_object('avatars', avatar_url) as result;_34end;_34$$;
Next, add a trigger that removes any obsolete avatar whenever the profile is updated or deleted:
_32create or replace function delete_old_avatar()_32returns trigger_32language 'plpgsql'_32security definer_32as $$_32declare_32 status int;_32 content text;_32 avatar_name text;_32begin_32 if coalesce(old.avatar_url, '') <> ''_32 and (tg_op = 'DELETE' or (old.avatar_url <> new.avatar_url)) then_32 -- extract avatar name_32 avatar_name := old.avatar_url;_32 select_32 into status, content_32 result.status, result.content_32 from public.delete_avatar(avatar_name) as result;_32 if status <> 200 then_32 raise warning 'Could not delete avatar: % %', status, content;_32 end if;_32 end if;_32 if tg_op = 'DELETE' then_32 return old;_32 end if;_32 return new;_32end;_32$$;_32_32create trigger before_profile_changes_32 before update of avatar_url or delete on public.profiles_32 for each row execute function public.delete_old_avatar();
Finally, delete the public.profile
row before a user is deleted.
If this step is omitted, you won't be able to delete users without
first manually deleting their avatar image.
_14create or replace function delete_old_profile()_14returns trigger_14language 'plpgsql'_14security definer_14as $$_14begin_14 delete from public.profiles where id = old.id;_14 return old;_14end;_14$$;_14_14create trigger before_delete_user_14 before delete on auth.users_14 for each row execute function public.delete_old_profile();
At this stage you have a fully functional application!
See also#
- See the complete example on GitHub and deploy it to Vercel
- Build a Twitter Clone with the Next.js App Router and Supabase - free egghead course
- Explore the pre-built Auth UI for React
- Explore the Auth Helpers for Next.js
- Explore the Supabase Cache Helpers
- See the Next.js Subscription Payments Starter template on GitHub