/* Right to left languages */
code {
  direction: ltr;
  display: inline-block;
}

.illustration {
  margin-top: 2em;
  margin-bottom: 2em;
}

/* Screenshots */
/*
Simulate a browser window frame.
Inspired by Termynal's CSS tricks with modifications
*/

.screenshot {
  display: block;
  background-color: #d3e0de;
  border-radius: 4px;
  padding: 45px 5px 5px;
  position: relative;

  Mailing Lists:      https://maven.apache.org/mailing-lists.html
  Source Code:        https://gitbox.apache.org/repos/asf/maven.git
  Issue Tracking:     https://issues.apache.org/jira/browse/MNG
  Wiki:               https://cwiki.apache.org/confluence/display/MAVEN/

   * {@link java.util.Collections#checkedCollection(java.util.Collection, Class)} can suppress it
   * with {@code FeatureSpecificTestSuiteBuilder.suppressing()} until <a
   * href="https://bugs.openjdk.org/browse/JDK-6409434">JDK-6409434</a> is fixed. It's unclear
   * whether nulls were to be permitted or forbidden, but presumably the eventual fix will be to

   * {@link java.util.Collections#checkedCollection(java.util.Collection, Class)} can suppress it
   * with {@code FeatureSpecificTestSuiteBuilder.suppressing()} until <a
   * href="https://bugs.openjdk.org/browse/JDK-6409434">JDK-6409434</a> is fixed. It's unclear
   * whether nulls were to be permitted or forbidden, but presumably the eventual fix will be to

that custom proprietary headers can be added <a href="https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers" class="external-link" target="_blank">using the 'X-' prefix</a>.

But if you have custom headers that you want a client in a browser to be able to see, you need to add them to your CORS configurations (read more in [CORS (Cross-Origin Resource Sharing)](../tutorial/cors.md){.internal-link target=_blank}), using the parameter `expose_headers` documented in <a href="https://www....

        What is the problem, question, or error?

        Write a short description telling me what you are doing, what you expect to happen, and what is currently happening.
      placeholder: |
        * Open the browser and call the endpoint `/`.
        * It returns a JSON with `{"Hello": "World"}`.
        * But I expected it to return `{"Hello": "Sara"}`.
    validations:
      required: true
  - type: dropdown
    id: os

<div class="termy">

```console
$ fastapi dev main.py

<span style="color: green;">INFO</span>:     Uvicorn running on http://127.0.0.1:8000 (Press CTRL+C to quit)
```

</div>

Abrar seu browser em: <a href="http://127.0.0.1:8000" class="external-link" target="_blank">http://127.0.0.1:8000</a>.

Lá você pode definir:

* O "Item ID", usado na rota.
* O "Token" usado como um parâmetro de consulta.

<img src="/img/tutorial/sub-applications/image02.png">

If you try interacting with any of the two user interfaces, they will work correctly, because the browser will be able to talk to each specific app or sub-app.

### Technical Details: `root_path` { #technical-details-root-path }

	// accordingly. Client receives a HTTP error for invalid/unsupported
	// signatures.
	//
	// Validates all incoming requests to have a valid date header.
	setAuthMiddleware,
	// Redirect some pre-defined browser request paths to a static location
	// prefix.
	setBrowserRedirectMiddleware,
	// Adds 'crossdomain.xml' policy middleware to serve legacy flash clients.
	setCrossDomainPolicyMiddleware,

```mermaid
graph LR

browser("Navegador")
proxy["Proxy en http://0.0.0.0:9999/api/v1/app"]
server["Servidor en http://127.0.0.1:8000/app"]

browser --> proxy
proxy --> server
```

/// tip | Consejo