Відкрийте браузер та введіть адресу <a href="http://127.0.0.1:8000" class="external-link" target="_blank">http://127.0.0.1:8000</a>.

Ви побачите у відповідь таке повідомлення у форматі JSON:

```JSON
{"message": "Hello World"}
```

### Інтерактивна API документація

Перейдемо сюди <a href="http://127.0.0.1:8000/docs" class="external-link" target="_blank">http://127.0.0.1:8000/docs</a>.

### Kiểm tra

Mở trình duyệt của bạn tại <a href="http://127.0.0.1:8000" class="external-link" target="_blank">http://127.0.0.1:8000</a>.

Bạn sẽ thấy một JSON response như:

```JSON
{"message": "Hello World"}
```

### Tài liệu tương tác API

Bây giờ tới <a href="http://127.0.0.1:8000/docs" class="external-link" target="_blank">http://127.0.0.1:8000/docs</a>.

For example, if you have a function:

```Python
@lru_cache
def say_hi(name: str, salutation: str = "Ms."):
    return f"Hello {salutation} {name}"
```

your program could execute like this:

```mermaid
sequenceDiagram

participant code as Code
participant function as say_hi()
participant execute as Execute function

   * that tests equivalence using their lengths:
   *
   * <pre>{@code
   * equiv.wrap("a").equals(equiv.wrap("b")) // true
   * equiv.wrap("a").equals(equiv.wrap("hello")) // false
   * }</pre>
   *
   * <p>Note in particular that an equivalence wrapper is never equal to the object it wraps.
   *
   * <pre>{@code
   * equiv.wrap(obj).equals(obj) // always false
   * }</pre>

  }

  public void testToStringWithNull() {
    Iterator<@Nullable String> iterator =
        Lists.<@Nullable String>newArrayList("hello", null, "world").iterator();
    assertEquals("[hello, null, world]", Iterators.toString(iterator));
  }

  public void testToStringEmptyIterator() {
    Iterator<String> iterator = Collections.<String>emptyList().iterator();

    val request =
      Request(
        server.url("/"),
        body = "Hello".toRequestBody("text/plain".toMediaType()),
      )
    val response = client.newCall(request).execute()
    assertThat(response.body.string()).isEqualTo("Body")
    val request1 = server.takeRequest()
    assertThat(request1.body.readUtf8()).isEqualTo("Hello")
    val request2 = server.takeRequest()

```

Bunun FastAPI'deki API <abbr title="Yol İşlemi: Path Operation">*yol işlemi*</abbr> şöyle görünür:

```Python hl_lines="1"
@app.get("/some/url")
def read_url():
    return {"message": "Hello World!"}
```

`requests.get(...)` ile `@app.get(...)` arasındaki benzerliklere bakın.

/// check | "**FastAPI**'a nasıl ilham verdi?"

* Basit ve sezgisel bir API'ya sahip olmalı.

```

Противоположная *операция пути* в FastAPI может выглядеть следующим образом:

```Python hl_lines="1"
@app.get("/some/url")
def read_url():
    return {"message": "Hello World"}
```

Глядите, как похоже `requests.get(...)` и `@app.get(...)`.

/// check | "Идеи для **FastAPI**"

* Должен быть простой и понятный API.

  }

  public void testToStringWithNull() {
    Iterator<@Nullable String> iterator =
        Lists.<@Nullable String>newArrayList("hello", null, "world").iterator();
    assertEquals("[hello, null, world]", Iterators.toString(iterator));
  }

  public void testToStringEmptyIterator() {
    Iterator<String> iterator = Collections.<String>emptyList().iterator();

* ✍ 🛁 📁 `__init__.py`.
* ✍ `main.py` 📁 ⏮️:

```Python
from typing import Union

from fastapi import FastAPI

app = FastAPI()


@app.get("/")
def read_root():
    return {"Hello": "World"}


@app.get("/items/{item_id}")
def read_item(item_id: int, q: Union[str, None] = None):
    return {"item_id": item_id, "q": q}
```

### 📁

🔜 🎏 🏗 📁 ✍ 📁 `Dockerfile` ⏮️: