# Debugging { #debugging }

You can connect the debugger in your editor, for example with Visual Studio Code or PyCharm.

## Call `uvicorn` { #call-uvicorn }

In your FastAPI application, import and run `uvicorn` directly:

{* ../../docs_src/debugging/tutorial001.py hl[1,15] *}

### About `__name__ == "__main__"` { #about-name-main }

The main purpose of the `__name__ == "__main__"` is to have some code that is executed when your file is called with:

Sie können mehrere `Form`-Parameter in einer *Pfadoperation* deklarieren, aber Sie können nicht gleichzeitig auch `Body`-Felder deklarieren, welche Sie als JSON erwarten, da der Request den Body mittels `application/x-www-form-urlencoded` statt `application/json` kodiert.

Das ist keine Limitation von **FastAPI**, sondern Teil des HTTP-Protokolls.

///

## Zusammenfassung

{* ../../docs_src/behind_a_proxy/tutorial004.py hl[9] *}

and then it won't include it in the OpenAPI schema.

## Mounting a sub-application { #mounting-a-sub-application }

If you need to mount a sub-application (as described in [Sub Applications - Mounts](sub-applications.md){.internal-link target=_blank}) while also using a proxy with `root_path`, you can do it normally, as you would expect.

 *    indicating that the call was canceled. The interceptor's exception is delivered to the current
 *    thread's [uncaught exception handler][Thread.UncaughtExceptionHandler]. By default this
 *    crashes the application on Android and prints a stacktrace on the JVM. (Crash reporting
 *    libraries may customize this behavior.)
 *
 * A good way to signal a failure is with a synthetic HTTP response:
 *
 * ```kotlin

            "content": {
                "application/json": {
                    "schema": {
                        "$ref": "#/components/schemas/Message"
                    }
                }
            }
        },
        "200": {
            "description": "Successful Response",
            "content": {
                "application/json": {
                    "schema": {

            "content": {
                "application/json": {
                    "schema": {
                        "$ref": "#/components/schemas/Message"
                    }
                }
            }
        },
        "200": {
            "description": "Successful Response",
            "content": {
                "application/json": {
                    "schema": {

But then the attackers try with username `stanleyjobsox` and password `love123`.

And your application code does something like:

```Python
if "stanleyjobsox" == "stanleyjobson" and "love123" == "swordfish":
    ...
```

### Java
```java
MockResponse response = new MockResponse.Builder()
    .addHeader("Content-Type", "application/json; charset=utf-8")
    .addHeader("Cache-Control", "no-cache")
    .body("{}")
    .build();
```

### Kotlin
```kotlin
val response = MockResponse.Builder()
  .addHeader("Content-Type", "application/json; charset=utf-8")
  .addHeader("Cache-Control", "no-cache")
  .body("{}")
  .build()
```

            "content": {
                "application/json": {
                    "schema": {
                        "$ref": "#/components/schemas/Message"
                    }
                }
            }
        },
        "200": {
            "description": "Successful Response",
            "content": {
                "application/json": {
                    "schema": {

import okio.BufferedSource
import okio.ByteString
import okio.use

/**
 * A one-shot stream from the origin server to the client application with the raw bytes of the
 * response body. Each response body is supported by an active connection to the webserver. This
 * imposes both obligations and limits on the client application.
 *
 * ### The response body must be closed.
 *