> ## Documentation Index
> Fetch the complete documentation index at: https://developers.gotolstoy.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Product update

# Product Update Guide

When updating product information through the API, especially when dealing with variants, there are specific rules that must be followed to ensure successful updates.

## Key Rules for Variant Updates

1. **Maintain Original Order**: The variants array must maintain the exact same order as received from Shopify
2. **Complete Array Required**: You must provide the entire variants array, even when updating a single variant
3. **Position Matters**: Each variant must remain in its original position in the array

## Allowed Fields

### Product Fields

You can only update these fields for products:

* `id`
* `description_html` (or `descriptionHtml` for backward compatibility)
* `variants`
* `price`
* `compare_at_price`
* `title`

### Variant Fields

You can only update these fields for variants:

* `id`
* `price`
* `compare_at_price`
* `title`

## Examples

### ❌ Incorrect Approach

This will not work - sending only the variant you want to update:

```javascript theme={null}
window.tolstoyWidget.postMessage({
  product: {
    id: "prod_123",
    variants: [
      {
        id: "var_2", // Second variant
        price: 29.99,
      },
    ],
  },
  eventName: "tolstoy_product_update",
});
```

### ✅ Correct Approach

Do this - send all variants in their original order:

```javascript theme={null}
window.tolstoyWidget.postMessage({
  product: {
    id: "prod_123",
    title: "Updated Product Title",
    description_html: "<p>New product description</p>",
    variants: [
      {
        id: "var_1", // Include first variant even if unchanged
      },
      {
        id: "var_2",
        price: 29.99, // Your update here
      },
      {
        id: "var_3", // Include third variant even if unchanged
      },
    ],
  },
  eventName: "tolstoy_product_update",
});
```

## Important Notes

* **Variant Order**: Must exactly match what you received from Shopify
* **All Variants Required**: Include all variants in the array, even ones you're not updating
* **Minimal Updates**: For unchanged variants, you only need to include their `id`
* **Field Validation**: Including fields not listed in the allowed fields will cause the update to fail

## Best Practice Example

Here's a complete example showing how to properly update a variant:

```javascript theme={null}
// Original product from Shopify has 3 variants
const originalVariants = [
  { id: "var_1", title: "Small", price: 19.99 },
  { id: "var_2", title: "Medium", price: 19.99 },
  { id: "var_3", title: "Large", price: 19.99 },
];

// To update product title and medium variant's price
window.tolstoyWidget.postMessage({
  product: {
    id: "prod_123",
    title: "Updated Product Name",
    variants: [
      { id: "var_1" }, // Keep first variant
      { id: "var_2", price: 24.99, title: "Medium Updated" }, // Update second variant
      { id: "var_3" }, // Keep third variant
    ],
  },
  eventName: "tolstoy_product_update",
});
```

## Request product  update

Async products update can be made with tolstoy\_request\_products\_update event. This could be used for example after language change:

```javascript theme={null}
const handle = '{{ product.handle }}';

window.tolstoyWidget.postMessage({
    eventName: 'tolstoy_request_products_update',
    handles: [handle],
});
```