# Generate customer portal access link by customer ID or email

Generates a secure, time-limited magic link that allows customers to access their subscription management portal. This endpoint supports lookup by either customer ID or email address, making it flexible for different integration scenarios.

Key Features:
- Dual Lookup: Find customer by ID or email
- Auto Customer Discovery: Automatically finds customer from email
- Secure Tokens: Encrypted tokens with 2-hour expiration
- Custom Domains: Supports shop's public domain
- Zero-Auth Access: Customers don't need passwords

Customer Lookup Logic:

Option 1: By Customer ID (Preferred)

GET /api/external/v2/manage-subscription-link?customerId=12345

- Direct lookup by Shopify customer ID
- Fastest and most reliable method
- No ambiguity

Option 2: By Email

GET /api/external/v2/manage-subscription-link?emailId=customer@example.com

- Searches for customer by email in subscription database
- Finds customer ID automatically
- If not found: Returns error

Validation Rules:
- Either customerId OR emailId must be provided
- Cannot provide both (customerId takes precedence)
- Email must match a customer with subscriptions
- Customer must belong to authenticated shop

Token Generation:

Token Contents:
- Encrypted customer ID
- Shop domain
- Generation timestamp
- Expiration time (2 hours)

Security Features:
- Cryptographically secure encryption
- Cannot be forged or modified
- Automatic expiration after 2 hours
- Single-use recommended (though not enforced)
- Tied to specific shop and customer

Generated URL Structure:

https://[shop-domain]/[manage-subscriptions-path]?token=[encrypted-token]


Example URLs:

https://mystore.com/tools/recurring/customer_portal?token=eyJhbGc...
https://shop.myshopify.com/tools/recurring/customer_portal?token=eyJhbGc...


Use Cases:

1. Email Campaigns:
- Add "Manage Subscription" button to transactional emails
- Include in billing reminder emails
- Send in order confirmation emails
- Add to marketing campaigns

2. Customer Support:
- Provide customers quick portal access
- Avoid "forgot password" issues
- Enable instant self-service
- Reduce support ticket volume

3. Post-Purchase Flows:
- Thank you page portal links
- First order welcome emails
- Onboarding email sequences
- Re-engagement campaigns

4. Account Management:
- SMS notifications with portal links
- Push notification deep links
- Customer dashboard integrations
- Third-party app integrations

Response Format:
json
{
  "manageSubscriptionLink": "https://mystore.com/tools/recurring/customer_portal?token=eyJhbGciOiJIUzI1NiJ9...",
  "tokenExpirationTime": "2024-03-15T14:30:00Z"
}


Response Fields:
- manageSubscriptionLink: Complete URL ready to use
- tokenExpirationTime: ISO 8601 timestamp when token expires

Integration Examples:

Email Template:
javascript
const response = await fetch(
  /api/external/v2/manage-subscription-link?emailId=${customerEmail},
  { headers: { 'X-API-Key': 'your-key' } }
).then(r => r.json());

const emailHtml = 
  Hi ${customerName},
  Manage your subscription:
  Manage Subscription
  Link expires ${formatDate(response.tokenExpirationTime)}
;


SMS Notification:
javascript
const { manageSubscriptionLink } = await getPortalLink(customerId);
const shortUrl = await shortenUrl(manageSubscriptionLink);

await sendSMS(customerPhone, 
  Your subscription ships tomorrow! Manage it here: ${shortUrl}
);


Important Considerations:

Token Expiration:
- Tokens expire after exactly 2 hours
- Generate new token if expired
- Don't store tokens long-term
- Best practice: Generate on-demand

Domain Selection:
- Uses shop's publicDomain if configured
- Falls back to Shopify domain (.myshopify.com)
- Respects custom domain settings
- Maintains brand consistency

Customer Lookup Errors:
- Email not found: Returns 400 error
- Invalid customer ID: Returns error
- No parameters provided: Returns 400
- Both parameters provided: Uses customerId

Security Notes:
- Tokens cannot be used across different shops
- Cannot be used for different customers
- Tampering invalidates token
- Consider rate limiting token generation

Best Practices:

1. Generate On-Demand: Create tokens when needed, not in advance
2. Use HTTPS: Always serve links over HTTPS
3. Show Expiry: Inform customers when link expires
4. URL Shortening: Use URL shorteners for SMS/print materials
5. Track Usage: Monitor which emails drive portal visits
6. Prefer Customer ID: Use customerId when available for faster lookup

Comparison with /manage-subscription-link/{customerId}:
- This endpoint: Flexible lookup (ID or email)
- Path parameter version: Customer ID only
- Both generate identical tokens
- Use this for email-based flows

Authentication: Requires valid X-API-Key header

Endpoint: GET /api/external/v2/manage-subscription-link
Version: 0.0.1

## Query parameters:

  - `api_key` (string)

  - `customerId` (integer)

  - `emailId` (string)

## Header parameters:

  - `X-API-Key` (string)

## Response 200 fields (application/json):

  - `manageSubscriptionLink` (string)

  - `tokenExpirationTime` (string)


## Response 400 fields

## Response 401 fields

## Response 403 fields

## Response 500 fields