clerk-migration-deep-dive

# Clerk Migration Deep Dive

## Overview
Comprehensive guide to migrating from other authentication providers to Clerk.

## Prerequisites
- Current auth provider access
- User data export capability
- Clerk account and API keys
- Migration timeline planned

## Migration Sources

### 1. Auth0 to Clerk

#### Step 1: Export Users from Auth0
```bash
# Using Auth0 Management API
curl -X GET "https://YOUR_DOMAIN.auth0.com/api/v2/users" \
  -H "Authorization: Bearer YOUR_MGMT_TOKEN" \
  -H "Content-Type: application/json" \
  > auth0-users.json
```

#### Step 2: Transform User Data
```typescript
// scripts/transform-auth0-users.ts
interface Auth0User {
  user_id: string
  email: string
  email_verified: boolean
  name: string
  given_name?: string
  family_name?: string
  picture?: string
  created_at: string
  last_login?: string
}

interface ClerkImportUser {
  external_id: string
  email_addresses: Array<{
    email_address: string
    verified: boolean
  }>
  first_name?: string
  last_name?: string
  image_url?: string
  created_at: string
  public_metadata?: Record<string, any>
}

function transformAuth0ToClerk(auth0User: Auth0User): ClerkImportUser {
  return {
    external_id: auth0User.user_id,
    email_addresses: [{
      email_address: auth0User.email,
      verified: auth0User.email_verified
    }],
    first_name: auth0User.given_name,
    last_name: auth0User.family_name,
    image_url: auth0User.picture,
    created_at: auth0User.created_at,
    public_metadata: {
      migrated_from: 'auth0',
      migrated_at: new Date().toISOString()
    }
  }
}
```

#### Step 3: Import to Clerk
```typescript
// scripts/import-to-clerk.ts
import { clerkClient } from '@clerk/nextjs/server'

async function importUsers(users: ClerkImportUser[]) {
  const client = await clerkClient()
  const results = { success: 0, failed: 0, errors: [] as string[] }

  for (const user of users) {
    try {
      await client.users.createUser({
        externalId: user.external_id,
        e