> For the complete documentation index, see [llms.txt](https://eventrix.gitbook.io/eventrix/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://eventrix.gitbook.io/eventrix/receivers/fetchhandler.md).

# fetchHandler

You can handle error using `catch` on promise as we do in fetch with eventrix section or use fetchHandler. Fetch handler is small midlerware for fetch method that emit events when fetch success or fetch error.

{% tabs %}
{% tab title="Javascript" %}

```jsx
import { fetchToStateReceiver, fetchHandler } from 'eventrix';
import axios from 'axios';

const fetchUsersMethod = (eventData, eventrixState, emit) => {
  return axios.get(https://somedomain.com/users, { params: eventData })
              .then((users) => {
                emit('fetchUsers.success', users);
                return users
              })
              .catch((error) => {
                emit('fetchUsers.error', error);
              });
};

const fetchUserMethodWithHandler = fetchHandler(
  fetchUsersMethod,
  {
    success: {
      eventName: 'fetchUsers.success',
      data: 'Users list loaded',
    },
    error: {
      eventName: 'fetchUsers.failed',
      data: 'Users list load failed',
    },
  }
);

const fetchReceiver = fetchToStateReceiver('fetchUsers', 'users', fetchUserMethodWithHandler);

eventrix.useReceiver(fetchReceiver);

eventrix.emit('fetchUsers', { search: 'johny' });
```

{% endtab %}
{% endtabs %}


---

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