# Fetching Data

## Fetch Data Through HTTP

There are two main ways to fetch data through HTTP in the Umbraco Backoffice:

* [Fetch API](#fetch-api)
* [Umbraco HTTP Client](#umbraco-http-client).

The Fetch API is a modern way to make network requests in JavaScript, while the Umbraco HTTP client is a wrapper around it, providing a more convenient interface.

For most scenarios, the Umbraco HTTP Client is recommended because it:

* Automatically handles authentication and error handling.
* Provides type safety for requests and responses.
* Simplifies request and response parsing.
* Integrates seamlessly with the Backoffice.

The Fetch API is an alternative for simpler use cases.

The following table provides a comparison of the two options:

| Feature              | [Fetch API](/umbraco-cms/18.latest/extend-your-project/backoffice-extensions/foundation/fetching-data/fetch-api.md) | [Umbraco HTTP Client](/umbraco-cms/18.latest/extend-your-project/backoffice-extensions/foundation/fetching-data/http-client.md) |
| -------------------- | ------------------------------------------------------------------------------------------------------------------- | ------------------------------------------------------------------------------------------------------------------------------- |
| Authentication       | Manual                                                                                                              | Automatic                                                                                                                       |
| Error Handling       | Manual                                                                                                              | Built-in                                                                                                                        |
| Type Safety          | No                                                                                                                  | Yes                                                                                                                             |
| Request Cancellation | Yes (via AbortController)                                                                                           | Yes (via AbortController)                                                                                                       |
| Recommended Use Case | Common requests                                                                                                     | Complex or frequent requests                                                                                                    |

After selecting a method, refer to the sections below for implementation details and guidance on handling the received data.

### [Fetch API](/umbraco-cms/18.latest/extend-your-project/backoffice-extensions/foundation/fetching-data/fetch-api.md)

The Fetch API is a modern way to make network requests in JavaScript. It provides a more powerful and flexible feature set than the older XMLHttpRequest.

### [Umbraco HTTP Client](/umbraco-cms/18.latest/extend-your-project/backoffice-extensions/foundation/fetching-data/http-client.md)

The Umbraco HTTP Client is a wrapper around the Fetch API that provides a more convenient way to make network requests. It handles request and response parsing, error handling, and retries.

## Handle Requests

Once you have chosen a method to fetch data, the next step is to handle the execution of requests. This includes managing errors, refreshing tokens, and ensuring proper authentication.

## [Executing Requests](/umbraco-cms/18.latest/extend-your-project/backoffice-extensions/foundation/fetching-data/try-execute.md)

After fetching data, the next step is to execute the request. You can use the `tryExecute` function to handle errors and refresh the token if it is expired.

## Advanced Topics

### [Custom Generated Client](/umbraco-cms/18.latest/extend-your-project/backoffice-extensions/foundation/fetching-data/custom-generated-client.md)

For advanced scenarios, you can generate a custom client for your API using tools like [@hey-api/openapi-ts](https://github.com/hey-api/openapi-ts). This approach is ideal when working with custom API controllers or when you need type-safe, reusable client code.

### [Repositories](/umbraco-cms/18.latest/extend-your-project/backoffice-extensions/foundation/repositories.md)

Repositories provide a structured way to manage data operations in the Backoffice. They abstract the data access layer, allowing for easier maintenance and scalability.


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