Use Supabase with iOS and SwiftUI

Learn how to create a Supabase project, add some sample data to your database, and query the data from an iOS app.

Create a Supabase project

Go to database.new and create a new Supabase project.

Alternatively, you can create a project using the Management API:

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# First, get your access token from https://supabase.com/dashboard/account/tokens
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export SUPABASE_ACCESS_TOKEN="your-access-token"
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# List your organizations to get the organization ID
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curl -H "Authorization: Bearer $SUPABASE_ACCESS_TOKEN" \
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  https://api.supabase.com/v1/organizations
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# Create a new project (replace <org-id> with your organization ID)
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curl -X POST https://api.supabase.com/v1/projects \
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  -H "Authorization: Bearer $SUPABASE_ACCESS_TOKEN" \
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  -H "Content-Type: application/json" \
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  -d '{
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    "organization_id": "<org-id>",
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    "name": "My Project",
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    "region": "us-east-1",
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    "db_pass": "<your-secure-password>"
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  }'

When your project is up and running, go to the Table Editor, create a new table and insert some data.

Alternatively, you can run the following snippet in your project's SQL Editor. This will create a instruments table with some sample data.

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-- Create the table
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create table instruments (
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  id bigint primary key generated always as identity,
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  name text not null
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);
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-- Insert some sample data into the table
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insert into instruments (name)
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values
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  ('violin'),
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  ('viola'),
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  ('cello');
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alter table instruments enable row level security;

Make the data in your table publicly readable by adding an RLS policy:

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create policy "public can read instruments"
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on public.instruments
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for select to anon
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using (true);

Create an iOS SwiftUI app with Xcode

Open Xcode > New Project > iOS > App. You can skip this step if you already have a working app.

Install the Supabase client library

Install Supabase package dependency using Xcode by following Apple's tutorial.

Make sure to add Supabase product package as dependency to the application.

Initialize the Supabase client

Create a new Supabase.swift file add a new Supabase instance using your project URL and public API (anon) key:

Project URL

Publishable key

Anon key

Supabase.swift

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import Supabase
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let supabase = SupabaseClient(
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  supabaseURL: URL(string: "YOUR_SUPABASE_URL")!,
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  supabaseKey: "YOUR_SUPABASE_PUBLISHABLE_KEY"
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)

You can also get the Project URL and key from the project's Connect dialog.

Changes to API keys

Supabase is changing the way keys work to improve project security and developer experience. You can read the full announcement, but in the transition period, you can use both the current anon and service_role keys and the new publishable key with the form sb_publishable_xxx which will replace the older keys.

In most cases, you can get the correct key from the Project's Connect dialog, but if you want a specific key, you can find all keys in the API Keys section of a Project's Settings page:

For legacy keys, copy the anon key for client-side operations and the service_role key for server-side operations from the Legacy API Keys tab.
For new keys, open the API Keys tab, if you don't have a publishable key already, click Create new API Keys, and copy the value from the Publishable key section.

Read the API keys docs for a full explanation of all key types and their uses.

Create a data model for instruments

Create a decodable struct to deserialize the data from the database.

Add the following code to a new file named Instrument.swift.

Supabase.swift

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struct Instrument: Decodable, Identifiable {
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  let id: Int
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  let name: String
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}

Query data from the app

Use a task to fetch the data from the database and display it using a List.

Replace the default ContentView with the following code.

ContentView.swift

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struct ContentView: View {
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  @State var instruments: [Instrument] = []
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  var body: some View {
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    List(instruments) { instrument in
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      Text(instrument.name)
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    }
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    .overlay {
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      if instruments.isEmpty {
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        ProgressView()
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      }
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    }
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    .task {
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      do {
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        instruments = try await supabase.from("instruments").select().execute().value
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      } catch {
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        dump(error)
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      }
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    }
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  }
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}

Start the app

Run the app on a simulator or a physical device by hitting Cmd + R on Xcode.