How to connect Supabase with PostgREST API?

 

Step 1: Set Up Supabase Project

 

1. Go to the Supabase website and create an account if you haven't already.
2. Once logged in, create a new project by clicking the "New Project" button.
3. Fill in the necessary details for your project, such as the name, organization, and database password.
4. Click on "Create New Project" to initiate the setup.

 

Step 2: Configure Supabase Database

 

1. After your project is created, you will be redirected to the project's dashboard.
2. Navigate to the "Database" section from the left-hand menu.
3. Here you can see the connection details for your database; make sure you note down the credentials as you will need them later.

 

Step 3: Enable API

 

1. In the project dashboard, navigate to the "API" section.
2. Here, you will find the details about your project's RESTful API.
3. Ensure the PostgREST API is enabled and take note of the URL as it will be essential for connecting clients.

 

Step 4: Configure PostgREST on Supabase

 

1. Head to the "Database" section and open the SQL editor.
2. Write SQL queries to define your database schema, tables, and functions as needed.
3. Each table and function you create will automatically be exposed by the PostgREST API provided by Supabase.

Example SQL for creating a table:

CREATE TABLE profiles (
  id SERIAL PRIMARY KEY,
  username TEXT UNIQUE,
  bio TEXT
);

 

Step 5: Test PostgREST API

 

1. Once your tables are set up, go back to the "API" tab.
2. From here, you can explore the RESTful endpoints automatically generated by PostgREST.
3. Use a tool like Postman or curl command to test these endpoints.

Example curl command to fetch all profiles:

curl -X GET 'https://your-project-ref.supabase.co/rest/v1/profiles' \\
-H "apikey: your_anon_key"

 

Step 6: Secure API Access

 

1. Navigate to the "Auth" section to manage user authentication and policies.
2. Utilize Supabase Auth to control access to the API by defining RLS (Row Level Security) policies.
3. In the SQL editor, write policies to control access to your database tables.

Example RLS policy to allow authenticated users to select from profiles:

CREATE POLICY "Allow authenticated read access" 
ON profiles 
FOR SELECT 
USING (auth.role() = 'authenticated');

 

Step 7: Integrate PostgREST API with Client Applications

 

1. Use any HTTP client library in your application to make API requests.
2. Include the API URL and necessary headers like API key or authentication token in your requests.

Example JavaScript fetch request:

fetch('https://your-project-ref.supabase.co/rest/v1/profiles', {
  method: 'GET',
  headers: {
    'apikey': 'your_anon_key',
    'Authorization': 'Bearer your_jwt_token'
  }
})
.then(response => response.json())
.then(data => console.log(data))
.catch(error => console.error('Error:', error));