Or you might have any other way to communicate with the WebSocket endpoint.

---

But for this example, we'll use a very simple HTML document with some JavaScript, all inside a long string.

This, of course, is not optimal and you wouldn't use it for production.

In production you would have one of the options above.

But it's the simplest way to focus on the server-side of WebSockets and have a working example:

    /**
     * Retrieve all addresses of a host by it's address. NetBIOS hosts can
     * have many names for a given IP address. The name and IP address make the
     * NetBIOS address. This provides a way to retrieve the other names for a
     * host with the same IP address.
     *
     * @param addr
     *            the address to query
     * @return resolved addresses
     * @throws UnknownHostException

    url: https://github.com/fastapi/fastapi/discussions/categories/questions
  - name: Feature Request
    about: To suggest an idea or ask about a feature, please start with a question saying what you would like to achieve. There might be a way to do it already.
    url: https://github.com/fastapi/fastapi/discussions/categories/questions
  - name: Show and tell
    about: Show what you built with FastAPI or to be used with FastAPI.

But at some point, there was no other option than creating something that provided all these features, taking the best ideas from previous tools, and combining them in the best way possible, using language features that weren't even available before (Python 3.6+ type hints).

## Previous tools

### <a href="https://www.djangoproject.com/" class="external-link" target="_blank">Django</a>

/// warning

The recommended way to handle the *startup* and *shutdown* is using the `lifespan` parameter of the `FastAPI` app as described above. If you provide a `lifespan` parameter, `startup` and `shutdown` event handlers will no longer be called. It's all `lifespan` or all events, not both.

You can probably skip this part.

///

import java.lang.annotation.Retention;
import java.lang.annotation.Target;
import javax.annotation.Nonnull;
import javax.annotation.meta.TypeQualifierDefault;

/**
 * Marks all "top-level" types as non-null in a way that is recognized by Kotlin. Note that this
 * unfortunately includes type-variable usages, so we also provide {@link ParametricNullness} to
 * "undo" it as best we can.
 */
@GwtCompatible
@Retention(RUNTIME)
@Target(TYPE)

# Response Status Code

The same way you can specify a response model, you can also declare the HTTP status code used for the response with the parameter `status_code` in any of the *path operations*:

* `@app.get()`
* `@app.post()`
* `@app.put()`
* `@app.delete()`
* etc.

{* ../../docs_src/response_status_code/tutorial001.py hl[6] *}

/// note

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DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
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(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE

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CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
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