How to fix identity_not_found: Identity does not exist in Supabase

import { createClient } from '@supabase/supabase-js'

const supabaseAdmin = createClient(
  process.env.SUPABASE_URL!,
  process.env.SUPABASE_SERVICE_ROLE_KEY!
)

// Check for a specific identity by provider and provider ID
const { data: identities, error } = await supabaseAdmin
  .from('auth.identities')
  .select('*')
  .eq('provider', 'github')
  .eq('provider_id', '123456789') // The provider's user ID
  .single()

if (error) {
  console.log('Identity not found or query error:', error.message)
} else {
  console.log('Identity exists:', identities)
}

SELECT id, user_id, provider, provider_id, identity_data, created_at, updated_at
FROM auth.identities
WHERE provider = 'github' AND provider_id = '123456789';

// For OAuth providers, trigger a new OAuth flow
const { data, error } = await supabase.auth.signInWithOAuth({
  provider: 'github',
  options: {
    redirectTo: 'https://yourapp.com/auth/callback'
  }
})

if (error) {
  console.error('OAuth error:', error.message)
} else {
  // User will be redirected to GitHub for authentication
  // Upon return, the identity will be recreated
}

// Use the Management API to create or update the user
const { data, error } = await supabaseAdmin.auth.admin.updateUserById(
  userId,
  {
    email: 'user@example.com',
    password: 'new-password-if-needed'
  }
)

// Check all identities for a specific provider ID
const { data: allIdentities, error } = await supabaseAdmin
  .from('auth.identities')
  .select('user_id, provider, provider_id')
  .eq('provider_id', '123456789') // The provider's user ID

if (allIdentities && allIdentities.length > 0) {
  console.log('This identity is associated with user(s):', allIdentities)

  // If it's associated with a different user than expected
  const expectedUserId = 'expected-user-uuid'
  const actualUserIds = allIdentities.map(id => id.user_id)

  if (!actualUserIds.includes(expectedUserId)) {
    console.log('Identity belongs to different user(s): ' + actualUserIds.join(', '))
    console.log('Expected it to belong to: ' + expectedUserId)
  }
}

import { isAuthApiError } from '@supabase/supabase-js'

try {
  const { data, error } = await supabase.auth.linkIdentity({
    provider: 'github'
  })

  if (error) {
    if (isAuthApiError(error) && error.code === 'identity_not_found') {
      // User-friendly message
      setErrorMessage(
        'Unable to link your GitHub account. The account connection appears to be missing. ' +
        'Please try signing in with GitHub again to re-establish the connection.'
      )

      // Log for debugging
      console.error('Identity not found details:', {
        code: error.code,
        status: error.status,
        message: error.message
      })
    }
  }
} catch (error) {
  console.error('Unexpected error:', error)
}

if (error?.code === 'identity_not_found') {
  // The identity is already gone, so operation is effectively successful
  console.log('Identity already removed, cleaning up UI state')
  removeProviderFromUI('github')
}

// Regular audit of user-identity associations
async function auditUserIdentities(userId) {
  const { data: user } = await supabaseAdmin.auth.admin.getUserById(userId)
  const { data: identities } = await supabaseAdmin
    .from('auth.identities')
    .select('*')
    .eq('user_id', userId)

  console.log('User ' + userId + ' has ' + (identities?.length || 0) + ' identities')

  // Check for common issues
  if (user && identities && identities.length === 0) {
    console.warn('User ' + userId + ' has no identities - this may cause auth issues')
    // Implement recovery logic or alert
  }
}

// Add database constraints or triggers if you have direct access
// (Note: Requires database access beyond standard Supabase API)

// Implement backup of critical auth data
async function backupAuthData() {
  // Export auth.users and auth.identities regularly
  // Store backups securely for disaster recovery
}