# Storefront API

Querying the Storefront API.

```jsx
import {useEffect, useState} from 'react';
import {
  useApi,
  reactExtension,
  List,
  ListItem,
} from '@shopify/ui-extensions-react/checkout';

export default reactExtension(
  'purchase.checkout.block.render',
  () => <Extension />,
);

function Extension() {
  const [data, setData] = useState();
  const {query} = useApi();

  useEffect(() => {
    query(
      `query ($first: Int!) {
        products(first: $first) {
          nodes {
            id
            title
          }
        }
      }`,
      {
        variables: {first: 5},
      },
    )
      .then(({data, errors}) => setData(data))
      .catch(console.error);
  }, [query]);

  return (
    <List>
      {data?.products?.nodes.map((node) => (
        <ListItem key={node.id}>
          {node.title}
        </ListItem>
      ))}
    </List>
  );
}

```

```js
import {
  extension,
  List,
  ListItem,
} from '@shopify/ui-extensions/checkout';

export default extension(
  'purchase.checkout.block.render',
  (root, {query}) => {
    query<any>(
      `query ($first: Int!) {
      products(first: $first) {
        nodes {
          id
          title
        }
      }
    }`,
      {
        variables: {first: 5},
      },
    )
      .then(({data}) => {
        const listItems =
          data?.products?.nodes.map((node) =>
            root.createComponent(
              ListItem,
              undefined,
              node.title,
            ),
          );

        root.appendChild(
          root.createComponent(
            List,
            undefined,
            listItems,
          ),
        );
      })
      .catch(console.error);
  },
);

```

## StandardApi

The base API object provided to `purchase` extension targets.

### Docs_Standard_QueryApi

### query

value: `<Data = unknown, Variables = Record<string, unknown>>(query: string, options?: { variables?: Variables; version?: StorefrontApiVersion; }) => Promise<{ data?: Data; errors?: GraphQLError[]; }>`

The method used to query the Storefront GraphQL API with a prefetched token.

Refer to [Storefront API access examples](https://shopify.dev/docs/api/checkout-ui-extensions/apis/storefront-api) for more information.

### GraphQLError

GraphQL error returned by the Shopify Storefront APIs.

### extensions

value: `{ requestId: string; code: string; }`


### message

value: `string`


## Related

- [Targets](https://shopify.dev/docs/api/checkout-ui-extensions/targets)
- [Components](https://shopify.dev/docs/api/checkout-ui-extensions/components)
- [Configuration](https://shopify.dev/docs/api/checkout-ui-extensions/configuration)
- [Tutorials](/apps/checkout)

## Examples

Querying the Storefront API.



You can access the [Storefront GraphQL API](https://shopify.dev/docs/api/storefront) using global `fetch()`.
Ensure your extension can access the Storefront API via the [`api_access` capability](https://shopify.dev/docs/api/checkout-ui-extensions/configuration#api-access).
      

```jsx
import {useEffect, useState} from 'react';
import {
  useApi,
  reactExtension,
  List,
  ListItem,
} from '@shopify/ui-extensions-react/checkout';

export default reactExtension(
  'purchase.checkout.block.render',
  () => <Extension />,
);

function Extension() {
  const {shop} = useApi();
  const [data, setData] = useState();

  useEffect(() => {
    const getProductsQuery = {
      query: `query ($first: Int!) {
        products(first: $first) {
          nodes {
            id
            title
          }
        }
      }`,
      variables: {first: 5},
    };

    const apiVersion = 'unstable';

    fetch(
      `${shop.storefrontUrl}api/${apiVersion}/graphql.json`,
      {
        method: 'POST',
        headers: {
          'Content-Type': 'application/json',
        },
        body: JSON.stringify(getProductsQuery),
      },
    )
      .then((response) => response.json())
      .then(({data, errors}) => setData(data))
      .catch(console.error);
  }, [shop]);

  return (
    <List>
      {data?.products?.nodes.map((node) => (
        <ListItem key={node.id}>
          {node.title}
        </ListItem>
      ))}
    </List>
  );
}

```

```js
import {
  extension,
  List,
  ListItem,
} from '@shopify/ui-extensions/checkout';

export default extension(
  'purchase.checkout.block.render',
  (root, {shop}) => {
    const apiVersion = 'unstable';
    const getProductsQuery = {
      query: `query ($first: Int!) {
      products(first: $first) {
        nodes {
          id
          title
        }
      }
    }`,
      variables: {first: 5},
    };

    fetch(
      `${shop.storefrontUrl}api/${apiVersion}/graphql.json`,
      {
        method: 'POST',
        headers: {
          'Content-Type': 'application/json',
        },
        body: JSON.stringify(getProductsQuery),
      },
    )
      .then((response) => response.json())
      .then(({data}) => {
        const listItems =
          data?.products?.nodes.map((node) =>
            root.createComponent(
              ListItem,
              undefined,
              node.title,
            ),
          );

        root.appendChild(
          root.createComponent(
            List,
            undefined,
            listItems,
          ),
        );
      })
      .catch(console.error);
  },
);

```