OAuth providers (Google, GitHub) in Supabase - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to initialize Supabase client with the correct URL.

Supabase

const supabase = createClient('[1]', 'public-anon-key');

Drag options to blanks, or click blank then click option'

Ahttps://xyzcompany.supabase.co

Bhttp://localhost:3000

Chttps://api.github.com

Dhttps://google.com

Attempts:

3 left

💡 Hint

Common Mistakes

Using localhost URL instead of the Supabase project URL.

Using unrelated URLs like Google or GitHub.

The Supabase client needs the project URL to connect properly.

2fill in blank

medium

Complete the code to start OAuth sign-in with Google provider.

Supabase

const { data, error } = await supabase.auth.signInWithOAuth({ provider: '[1]' });

Drag options to blanks, or click blank then click option'

Agithub

Btwitter

Cfacebook

Dgoogle

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'GitHub' or other providers instead of 'google'.

Capitalizing the provider name incorrectly.

To sign in with Google, the provider must be set to 'google'.

3fill in blank

hard

Fix the error in the code to sign in with GitHub OAuth provider.

Supabase

const { data, error } = await supabase.auth.signInWithOAuth({ provider: '[1]' });

Drag options to blanks, or click blank then click option'

AgitHub

BGitHub

Cgithub

Dgit_hub

Attempts:

3 left

💡 Hint

Common Mistakes

Capitalizing provider name incorrectly.

Using underscores or camelCase in provider name.

The provider name must be all lowercase 'github' to work correctly.

4fill in blank

hard

Fill both blanks to configure OAuth redirect URL and scopes for GitHub.

Supabase

const { data, error } = await supabase.auth.signInWithOAuth({ provider: 'github', options: { redirectTo: '[1]', scopes: '[2]' } });

Drag options to blanks, or click blank then click option'

Ahttps://myapp.com/callback

Bread:user

Cwrite:repo

Dhttps://example.com/redirect

Attempts:

3 left

💡 Hint

Common Mistakes

Using a wrong redirect URL not registered in GitHub app settings.

Using invalid or unsupported scopes.

The redirect URL must be your app's callback URL, and scopes define permissions like 'read:user'.

5fill in blank

hard

Fill all three blanks to handle OAuth sign-in and check for errors.

Supabase

try {
  const { data, error } = await supabase.auth.signInWithOAuth({ provider: '[1]' });
  if ([2]) {
    console.error('Error:', [3]);
  }
} catch (err) {
  console.error('Unexpected error:', err);
}

Drag options to blanks, or click blank then click option'

Agoogle

Berror

Cerror.message

Dgithub

Attempts:

3 left

💡 Hint

Common Mistakes

Using wrong provider string.

Checking wrong variable for errors.

Logging error object directly instead of its message.

Use 'github' as provider, check if 'error' exists, and log 'error.message' for details.

Practice

1. What does supabase.auth.signInWithOAuth({ provider: 'google' }) do in a Supabase app?

easy

A. Fetches user data without login

B. Creates a new Google account automatically

C. Deletes the current user session

D. Starts the login process using a Google account

Solution

1. Step 1: Understand the function purpose

   The function signInWithOAuth is used to start OAuth login with a specified provider.

2. Step 2: Identify the provider used

   Here, the provider is 'google', so it triggers Google OAuth login flow.

3. Final Answer:

   Starts the login process using a Google account -> Option D

4. Quick Check:

   OAuth login with Google = Starts login [OK]

Hint: OAuth signInWithOAuth starts login with chosen provider [OK]

Common Mistakes:

• Thinking it creates a new account automatically
• Confusing login start with data fetching
• Assuming it logs out the user

2. Which of the following is the correct syntax to start GitHub OAuth login in Supabase?

easy

A. supabase.auth.signInWithOAuth(provider='github')

B. supabase.auth.signInWithOAuth('github')

C. supabase.auth.signInWithOAuth({ provider: 'github' })

D. supabase.auth.signInWithOAuth({ provider: github })

Solution

1. Step 1: Check the method signature

   The method expects an object with a key named 'provider' and a string value.

2. Step 2: Validate each option

   supabase.auth.signInWithOAuth({ provider: 'github' }) correctly uses an object with provider as string 'github'. Others have syntax errors or missing quotes.

3. Final Answer:

   supabase.auth.signInWithOAuth({ provider: 'github' }) -> Option C

4. Quick Check:

   Correct object syntax with provider string = supabase.auth.signInWithOAuth({ provider: 'github' }) [OK]

Hint: Use object with provider key and string value for OAuth [OK]

Common Mistakes:

• Passing provider as a plain string without object
• Missing quotes around 'github'
• Using wrong parameter syntax

3. Given this code snippet, what will be the output if the user successfully logs in with GitHub?

const { data, error } = await supabase.auth.signInWithOAuth({ provider: 'github' });
console.log(data.session ? 'Logged in' : 'Not logged in');

medium

A. Not logged in

B. Logged in

C. Error thrown

D. Undefined

Solution

1. Step 1: Understand the signInWithOAuth response

   On successful login, data.session contains session info, so it is truthy.

2. Step 2: Evaluate the console.log condition

   The ternary checks if data.session exists; if yes, prints 'Logged in'.

3. Final Answer:

   Logged in -> Option B

4. Quick Check:

   Successful login means data.session truthy = 'Logged in' [OK]

Hint: Check if data.session exists to confirm login success [OK]

Common Mistakes:

• Assuming error is thrown on success
• Confusing data.session with error presence
• Ignoring async/await behavior

4. You wrote this code to start Google OAuth login:

supabase.auth.signInWithOAuth(provider: 'google');

Why does this cause an error?

medium

A. Missing curly braces around the object argument

B. Provider name should be uppercase 'Google'

C. signInWithOAuth does not accept any arguments

D. The method should be called on supabase.auth.user

Solution

1. Step 1: Check the argument syntax

   The method expects an object argument, so it must be wrapped in curly braces.

2. Step 2: Identify the error cause

   Passing provider: 'google' without braces is invalid syntax causing an error.

3. Final Answer:

   Missing curly braces around the object argument -> Option A

4. Quick Check:

   Object argument needs braces = Missing curly braces around the object argument [OK]

Hint: Always wrap provider in curly braces as an object [OK]

Common Mistakes:

• Using provider name with wrong case
• Calling method on wrong object
• Passing provider as plain string

5. You want users to sign in with either Google or GitHub using Supabase OAuth. Which setup step is essential before calling signInWithOAuth?

hard

A. Register your app and set redirect URLs in both Google and GitHub developer consoles

B. Create user accounts manually in Supabase for Google and GitHub users

C. Install Google and GitHub SDKs in your frontend app

D. Set environment variable SUPABASE_OAUTH_SECRET to 'true'

Solution

1. Step 1: Understand OAuth provider requirements

   OAuth providers require you to register your app and configure redirect URLs in their developer portals.

2. Step 2: Confirm necessary setup before login

   Without this setup, OAuth login will fail or redirect incorrectly.

3. Final Answer:

   Register your app and set redirect URLs in both Google and GitHub developer consoles -> Option A

4. Quick Check:

   OAuth setup requires app registration and redirect URLs [OK]

Hint: Always register app and set redirect URLs before OAuth login [OK]

Common Mistakes:

• Thinking manual user creation is needed
• Assuming SDK installation is required
• Setting unrelated environment variables