Advanced/License Validation

License Validation API

Protect your software products by validating license keys from your application. When a customer purchases a serial-type product, Sellvy delivers a unique license key that you can verify server-side.

How it works

1You create a product of type serial and add license keys to the stock.
2When a customer buys your product, they receive a license key (e.g., XXXX-XXXX-XXXX-XXXX).
3Your application calls the validation endpoint to check if the key is valid, used, or revoked.

POST/v1/licenses/validate

Validate a license

Check whether a license key is valid. This endpoint does not require seller authentication — it uses your store slug and the license key itself.

Request body

Field	Type	Required	Description
store	string	Yes	Your store slug (e.g., “my-store”)
license_key	string	Yes	The license key to validate
product_id	string	No	Restrict validation to a specific product

const res = await fetch("https://api.sellvy.io/v1/licenses/validate", {
  method: "POST",
  headers: { "Content-Type": "application/json" },
  body: JSON.stringify({
    store: "my-store",
    license_key: "ABCD-1234-EFGH-5678"
  })
});

const result = await res.json();

if (result.valid) {
  console.log("License is valid!");
  console.log("Product:", result.product_title);
  console.log("Customer:", result.email);
} else {
  console.log("Invalid license:", result.error);
}

Response format

Valid license

json

{
  "valid": true,
  "license_key": "ABCD-1234-EFGH-5678",
  "product_id": "prod_abc123",
  "product_title": "My Software Pro",
  "email": "customer@example.com",
  "order_id": "ord_abc123",
  "activated_at": "2025-01-15T10:30:00Z",
  "expires_at": null
}

Invalid license

json

{
  "valid": false,
  "error": "license_not_found"
}

Error codes

Error	Description
license_not_found	No license with this key exists in the store.
license_revoked	The license has been revoked by the seller (e.g., after a refund).
license_expired	The license has passed its expiration date.
product_mismatch	The license belongs to a different product than the one specified.

POST/v1/licenses/revoke

Revoke a license

Revoke a license key so it no longer passes validation. Requires seller API key authentication. Commonly used after processing a refund.

const res = await fetch("https://api.sellvy.io/v1/licenses/revoke", {
  method: "POST",
  headers: {
    "Authorization": "Bearer sk_live_...",
    "Content-Type": "application/json"
  },
  body: JSON.stringify({
    license_key: "ABCD-1234-EFGH-5678"
  })
});

const result = await res.json();
console.log(result.revoked); // true

Integration example

Here is a complete example of how to integrate license validation into your application's startup:

async function checkLicense(licenseKey) {
  try {
    const res = await fetch("https://api.sellvy.io/v1/licenses/validate", {
      method: "POST",
      headers: { "Content-Type": "application/json" },
      body: JSON.stringify({
        store: "my-store",
        license_key: licenseKey,
        product_id: "prod_my_software"
      })
    });

    const data = await res.json();

    if (!data.valid) {
      console.error(`License invalid: ${data.error}`);
      process.exit(1);
    }

    console.log(`Licensed to: ${data.email}`);
    return data;
  } catch (err) {
    // Network error — allow offline grace period
    console.warn("Could not verify license (offline)");
    return null;
  }
}

// On app startup
const license = await checkLicense(process.env.LICENSE_KEY);

Best practices

•Cache validation results — do not call the API on every request. Validate on startup and periodically (e.g., every 24 hours).
•Handle offline gracefully — if the API is unreachable, allow a grace period using the last cached result.
•Use product_id for specificity — include the product_id to ensure the key belongs to the correct product.
•Auto-revoke on refund — use the order.refunded webhook to automatically revoke the associated license.

SellvyPay SDK

Was this page helpful?