Це схоже на HTTP статус-коди 200 (від 200 до 299). Ці "200" статус-коди означають, що запит пройшов успішно.

Статус-коди в діапазоні 400 означають, що сталася помилка з боку клієнта.

Пам'ятаєте всі ці помилки **404 Not Found** (і жарти про них)?

## Використання `HTTPException`

Щоб повернути HTTP-відповіді з помилками клієнту, використовуйте `HTTPException`.

### Імпорт `HTTPException`

    /*
     * uncheckedCastNullableTToT is safe as long as the callers are careful to pass a "real" T
     * whenever they pass `true` for the matching `has*Bound` parameter.
     */
    if (hasLowerBound) {
      int unused =
          comparator.compare(
              uncheckedCastNullableTToT(lowerEndpoint), uncheckedCastNullableTToT(lowerEndpoint));
    }

    if [ -n "$MAVEN_DEBUG_SCRIPT" ]; then
      echo "[DEBUG] Found jvm.config file at: $1" >&2
      echo "[DEBUG] Running JvmConfigParser with Java: $JAVACMD" >&2
      echo "[DEBUG] Parser arguments: $MAVEN_HOME/bin/JvmConfigParser.java $1 $MAVEN_PROJECTBASEDIR" >&2
    fi

    # Verify Java is available
    "$JAVACMD" -version >/dev/null 2>&1 || {
      echo "Error: Java not found. Please set JAVA_HOME." >&2
      return 1
    }

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

</div>

すると、以下のように `/openapi.json`, `/docs`, `/redoc` のどのURLにアクセスしても、 `404 Not Found` エラーが返ってくるようになります。

```JSON
{
    "detail": "Not Found"
}

                    pluginArtifact,
                    "Plugin should declare Maven artifacts in `provided` scope. If the plugin already declares them in `provided` scope, update the maven-plugin-plugin to latest version. Artifacts found with wrong scope: "
                            + mavenArtifacts);
        }
    }

// Copyright 2015 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.

/*
Asm, typically invoked as “go tool asm”, assembles the source file into an object
file named for the basename of the argument source file with a .o suffix. The
object file can then be combined with other objects into a package archive.

# Command Line

Usage:

	go tool asm [flags] file

// Copyright 2018 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.

package asm

import (
	"cmd/asm/internal/lex"
	"strings"
	"testing"
)

type badInstTest struct {
	input, error string
}

func TestAMD64BadInstParser(t *testing.T) {
	testBadInstParser(t, "amd64", []badInstTest{
		// Test AVX512 suffixes.

    if x_token != fake_secret_token:
        raise HTTPException(status_code=400, detail="Invalid X-Token header")
    if item_id not in fake_db:
        raise HTTPException(status_code=404, detail="Item not found")
    return fake_db[item_id]


@app.post("/items/", response_model=Item)
async def create_item(item: Item, x_token: Annotated[str, Header()]):
    if x_token != fake_secret_token:

package cmd

import (
	"errors"
)

var (
	errLockConflict       = errors.New("lock conflict")
	errLockNotInitialized = errors.New("lock not initialized")
	errLockNotFound       = errors.New("lock not found")

```

Mas se o cliente faz uma requisição para `http://example.com/items/bar` (ou seja, um não existente `item_id "bar"`), esse cliente receberá um HTTP status code 404 (o erro "não encontrado" — *not found error*), e uma resposta JSON:

```JSON
{
  "detail": "Item not found"
}
```

/// tip | Dica

Quando você lançar um `HTTPException`, você pode passar qualquer valor convertível em JSON como parâmetro de `detail`, e não apenas `str`.