tiangolo.fastapi/docs/em/docs/tutorial/query-params-str-validations.md

🔢 🔢 & 🎻 🔬

FastAPI ✔ 👆 📣 🌖 ℹ & 🔬 👆 🔢.

➡️ ✊ 👉 🈸 🖼:

=== "🐍 3️⃣.6️⃣ & 🔛"

```Python hl_lines="9"
{!> ../../../docs_src/query_params_str_validations/tutorial001.py!}
```

=== "🐍 3️⃣.1️⃣0️⃣ & 🔛"

```Python hl_lines="7"
{!> ../../../docs_src/query_params_str_validations/tutorial001_py310.py!}
```

🔢 🔢 q 🆎 Union[str, None] (⚖️ str | None 🐍 3️⃣.1️⃣0️⃣), 👈 ⛓ 👈 ⚫️ 🆎 str ✋️ 💪 None, & 👐, 🔢 💲 None, FastAPI 🔜 💭 ⚫️ 🚫 ✔.

!!! note FastAPI 🔜 💭 👈 💲 q 🚫 ✔ ↩️ 🔢 💲 = None.

 `Union` `Union[str, None]` 🔜 ✔ 👆 👨‍🎨 🤝 👆 👍 🐕‍🦺 & 🔍 ❌.

🌖 🔬

👥 🔜 🛠️ 👈 ✋️ q 📦, 🕐❔ ⚫️ 🚚, 🚮 📐 🚫 📉 5️⃣0️⃣ 🦹.

🗄 Query

🏆 👈, 🥇 🗄 Query ⚪️➡️ fastapi:

=== "🐍 3️⃣.6️⃣ & 🔛"

```Python hl_lines="3"
{!> ../../../docs_src/query_params_str_validations/tutorial002.py!}
```

=== "🐍 3️⃣.1️⃣0️⃣ & 🔛"

```Python hl_lines="1"
{!> ../../../docs_src/query_params_str_validations/tutorial002_py310.py!}
```

⚙️ Query 🔢 💲

& 🔜 ⚙️ ⚫️ 🔢 💲 👆 🔢, ⚒ 🔢 max_length 5️⃣0️⃣:

=== "🐍 3️⃣.6️⃣ & 🔛"

```Python hl_lines="9"
{!> ../../../docs_src/query_params_str_validations/tutorial002.py!}
```

=== "🐍 3️⃣.1️⃣0️⃣ & 🔛"

```Python hl_lines="7"
{!> ../../../docs_src/query_params_str_validations/tutorial002_py310.py!}
```

👥 ✔️ ❎ 🔢 💲 None 🔢 ⏮️ Query(), 👥 💪 🔜 ⚒ 🔢 💲 ⏮️ 🔢 Query(default=None), ⚫️ 🍦 🎏 🎯 ⚖ 👈 🔢 💲.

:

q: Union[str, None] = Query(default=None)

...⚒ 🔢 📦, 🎏:

q: Union[str, None] = None

& 🐍 3️⃣.1️⃣0️⃣ & 🔛:

q: str | None = Query(default=None)

...⚒ 🔢 📦, 🎏:

q: str | None = None

✋️ ⚫️ 📣 ⚫️ 🎯 💆‍♂ 🔢 🔢.

!!! info ✔️ 🤯 👈 🌅 ⚠ 🍕 ⚒ 🔢 📦 🍕:

```Python
= None
```

⚖️:

```Python
= Query(default=None)
```

⚫️ 🔜 ⚙️ 👈 `None` 🔢 💲, & 👈 🌌 ⚒ 🔢 **🚫 ✔**.

 `Union[str, None]` 🍕 ✔ 👆 👨‍🎨 🚚 👻 🐕‍🦺, ✋️ ⚫️ 🚫 ⚫️❔ 💬 FastAPI 👈 👉 🔢 🚫 ✔.

⤴️, 👥 💪 🚶‍♀️ 🌅 🔢 Query. 👉 💼, max_length 🔢 👈 ✔ 🎻:

q: Union[str, None] = Query(default=None, max_length=50)

👉 🔜 ✔ 📊, 🎦 🆑 ❌ 🕐❔ 📊 🚫 ☑, & 📄 🔢 🗄 🔗 ➡ 🛠️.

🚮 🌅 🔬

👆 💪 🚮 🔢 min_length:

=== "🐍 3️⃣.6️⃣ & 🔛"

```Python hl_lines="10"
{!> ../../../docs_src/query_params_str_validations/tutorial003.py!}
```

=== "🐍 3️⃣.1️⃣0️⃣ & 🔛"

```Python hl_lines="7"
{!> ../../../docs_src/query_params_str_validations/tutorial003_py310.py!}
```

🚮 🥔 🧬

👆 💪 🔬 🥔 🧬 👈 🔢 🔜 🏏:

=== "🐍 3️⃣.6️⃣ & 🔛"

```Python hl_lines="11"
{!> ../../../docs_src/query_params_str_validations/tutorial004.py!}
```

=== "🐍 3️⃣.1️⃣0️⃣ & 🔛"

```Python hl_lines="9"
{!> ../../../docs_src/query_params_str_validations/tutorial004_py310.py!}
```

👉 🎯 🥔 🧬 ✅ 👈 📨 🔢 💲:

• ^: ▶️ ⏮️ 📄 🦹, 🚫 ✔️ 🦹 ⏭.
• fixedquery: ✔️ ☑ 💲 fixedquery.
• $: 🔚 📤, 🚫 ✔️ 🙆 🌖 🦹 ⏮️ fixedquery.

🚥 👆 💭 💸 ⏮️ 🌐 👉 "🥔 🧬" 💭, 🚫 😟. 👫 🏋️ ❔ 📚 👫👫. 👆 💪 📚 💩 🍵 💆‍♂ 🥔 🧬.

✋️ 🕐❔ 👆 💪 👫 & 🚶 & 💡 👫, 💭 👈 👆 💪 ⏪ ⚙️ 👫 🔗 FastAPI.

🔢 💲

🎏 🌌 👈 👆 💪 🚶‍♀️ None 💲 default 🔢, 👆 💪 🚶‍♀️ 🎏 💲.

➡️ 💬 👈 👆 💚 📣 q 🔢 🔢 ✔️ min_length 3, & ✔️ 🔢 💲 "fixedquery":

{!../../../docs_src/query_params_str_validations/tutorial005.py!}

!!! note ✔️ 🔢 💲 ⚒ 🔢 📦.

⚒ ⚫️ ✔

🕐❔ 👥 🚫 💪 📣 🌅 🔬 ⚖️ 🗃, 👥 💪 ⚒ q 🔢 🔢 ✔ 🚫 📣 🔢 💲, 💖:

q: str

↩️:

q: Union[str, None] = None

✋️ 👥 🔜 📣 ⚫️ ⏮️ Query, 🖼 💖:

q: Union[str, None] = Query(default=None, min_length=3)

, 🕐❔ 👆 💪 📣 💲 ✔ ⏪ ⚙️ Query, 👆 💪 🎯 🚫 📣 🔢 💲:

{!../../../docs_src/query_params_str_validations/tutorial006.py!}

✔ ⏮️ ❕ (...)

📤 🎛 🌌 🎯 📣 👈 💲 ✔. 👆 💪 ⚒ default 🔢 🔑 💲 ...:

{!../../../docs_src/query_params_str_validations/tutorial006b.py!}

!!! info 🚥 👆 🚫 👀 👈 ... ⏭: ⚫️ 🎁 👁 💲, ⚫️ 🍕 🐍 & 🤙 "❕".

⚫️ ⚙️ Pydantic & FastAPI 🎯 📣 👈 💲 ✔.

👉 🔜 ➡️ FastAPI 💭 👈 👉 🔢 ✔.

✔ ⏮️ None

👆 💪 📣 👈 🔢 💪 🚫 None, ✋️ 👈 ⚫️ ✔. 👉 🔜 ⚡ 👩‍💻 📨 💲, 🚥 💲 None.

👈, 👆 💪 📣 👈 None ☑ 🆎 ✋️ ⚙️ default=...:

=== "🐍 3️⃣.6️⃣ & 🔛"

```Python hl_lines="9"
{!> ../../../docs_src/query_params_str_validations/tutorial006c.py!}
```

=== "🐍 3️⃣.1️⃣0️⃣ & 🔛"

```Python hl_lines="7"
{!> ../../../docs_src/query_params_str_validations/tutorial006c_py310.py!}
```

!!! tip Pydantic, ❔ ⚫️❔ 🏋️ 🌐 💽 🔬 & 🛠️ FastAPI, ✔️ 🎁 🎭 🕐❔ 👆 ⚙️ Optional ⚖️ Union[Something, None] 🍵 🔢 💲, 👆 💪 ✍ 🌅 🔃 ⚫️ Pydantic 🩺 🔃 ✔ 📦 🏑.

⚙️ Pydantic Required ↩️ ❕ (...)

🚥 👆 💭 😬 ⚙️ ..., 👆 💪 🗄 & ⚙️ Required ⚪️➡️ Pydantic:

{!../../../docs_src/query_params_str_validations/tutorial006d.py!}

!!! tip 💭 👈 🌅 💼, 🕐❔ 🕳 🚚, 👆 💪 🎯 🚫 default 🔢, 👆 🛎 🚫 ✔️ ⚙️ ... 🚫 Required.

🔢 🔢 📇 / 💗 💲

🕐❔ 👆 🔬 🔢 🔢 🎯 ⏮️ Query 👆 💪 📣 ⚫️ 📨 📇 💲, ⚖️ 🙆‍♀ 🎏 🌌, 📨 💗 💲.

🖼, 📣 🔢 🔢 q 👈 💪 😑 💗 🕰 📛, 👆 💪 ✍:

=== "🐍 3️⃣.6️⃣ & 🔛"

```Python hl_lines="9"
{!> ../../../docs_src/query_params_str_validations/tutorial011.py!}
```

=== "🐍 3️⃣.9️⃣ & 🔛"

```Python hl_lines="9"
{!> ../../../docs_src/query_params_str_validations/tutorial011_py39.py!}
```

=== "🐍 3️⃣.1️⃣0️⃣ & 🔛"

```Python hl_lines="7"
{!> ../../../docs_src/query_params_str_validations/tutorial011_py310.py!}
```

⤴️, ⏮️ 📛 💖:

http://localhost:8000/items/?q=foo&q=bar

👆 🔜 📨 💗 q 🔢 🔢' 💲 (foo & bar) 🐍 list 🔘 👆 ➡ 🛠️ 🔢, 🔢 🔢 q.

, 📨 👈 📛 🔜:

{
  "q": [
    "foo",
    "bar"
  ]
}

!!! tip 📣 🔢 🔢 ⏮️ 🆎 list, 💖 🖼 🔛, 👆 💪 🎯 ⚙️ Query, ⏪ ⚫️ 🔜 🔬 📨 💪.

🎓 🛠️ 🩺 🔜 ℹ ➡️, ✔ 💗 💲:

🔢 🔢 📇 / 💗 💲 ⏮️ 🔢

& 👆 💪 🔬 🔢 list 💲 🚥 👌 🚚:

=== "🐍 3️⃣.6️⃣ & 🔛"

```Python hl_lines="9"
{!> ../../../docs_src/query_params_str_validations/tutorial012.py!}
```

=== "🐍 3️⃣.9️⃣ & 🔛"

```Python hl_lines="7"
{!> ../../../docs_src/query_params_str_validations/tutorial012_py39.py!}
```

🚥 👆 🚶:

http://localhost:8000/items/

🔢 q 🔜: ["foo", "bar"] & 👆 📨 🔜:

{
  "q": [
    "foo",
    "bar"
  ]
}

⚙️ list

👆 💪 ⚙️ list 🔗 ↩️ List[str] (⚖️ list[str] 🐍 3️⃣.9️⃣ ➕):

{!../../../docs_src/query_params_str_validations/tutorial013.py!}

!!! note ✔️ 🤯 👈 👉 💼, FastAPI 🏆 🚫 ✅ 🎚 📇.

🖼, `List[int]` 🔜 ✅ (& 📄) 👈 🎚 📇 🔢. ✋️ `list` 😞 🚫🔜.

📣 🌅 🗃

👆 💪 🚮 🌅 ℹ 🔃 🔢.

👈 ℹ 🔜 🔌 🏗 🗄 & ⚙️ 🧾 👩‍💻 🔢 & 🔢 🧰.

!!! note ✔️ 🤯 👈 🎏 🧰 5️⃣📆 ✔️ 🎏 🎚 🗄 🐕‍🦺.

👫 💪 🚫 🎦 🌐 ➕ ℹ 📣, 👐 🌅 💼, ❌ ⚒ ⏪ 📄 🛠️.

👆 💪 🚮 title:

=== "🐍 3️⃣.6️⃣ & 🔛"

```Python hl_lines="10"
{!> ../../../docs_src/query_params_str_validations/tutorial007.py!}
```

=== "🐍 3️⃣.1️⃣0️⃣ & 🔛"

```Python hl_lines="8"
{!> ../../../docs_src/query_params_str_validations/tutorial007_py310.py!}
```

& description:

=== "🐍 3️⃣.6️⃣ & 🔛"

```Python hl_lines="13"
{!> ../../../docs_src/query_params_str_validations/tutorial008.py!}
```

=== "🐍 3️⃣.1️⃣0️⃣ & 🔛"

```Python hl_lines="12"
{!> ../../../docs_src/query_params_str_validations/tutorial008_py310.py!}
```

📛 🔢

🌈 👈 👆 💚 🔢 item-query.

💖:

http://127.0.0.1:8000/items/?item-query=foobaritems

✋️ item-query 🚫 ☑ 🐍 🔢 📛.

🔐 🔜 item_query.

✋️ 👆 💪 ⚫️ ⚫️❔ item-query...

⤴️ 👆 💪 📣 alias, & 👈 📛 ⚫️❔ 🔜 ⚙️ 🔎 🔢 💲:

=== "🐍 3️⃣.6️⃣ & 🔛"

```Python hl_lines="9"
{!> ../../../docs_src/query_params_str_validations/tutorial009.py!}
```

=== "🐍 3️⃣.1️⃣0️⃣ & 🔛"

```Python hl_lines="7"
{!> ../../../docs_src/query_params_str_validations/tutorial009_py310.py!}
```

😛 🔢

🔜 ➡️ 💬 👆 🚫 💖 👉 🔢 🚫🔜.

👆 ✔️ 👈 ⚫️ 📤 ⏪ ↩️ 📤 👩‍💻 ⚙️ ⚫️, ✋️ 👆 💚 🩺 🎯 🎦 ⚫️ 😢.

⤴️ 🚶‍♀️ 🔢 deprecated=True Query:

=== "🐍 3️⃣.6️⃣ & 🔛"

```Python hl_lines="18"
{!> ../../../docs_src/query_params_str_validations/tutorial010.py!}
```

=== "🐍 3️⃣.1️⃣0️⃣ & 🔛"

```Python hl_lines="17"
{!> ../../../docs_src/query_params_str_validations/tutorial010_py310.py!}
```

🩺 🔜 🎦 ⚫️ 💖 👉:

🚫 ⚪️➡️ 🗄

🚫 🔢 🔢 ⚪️➡️ 🏗 🗄 🔗 (& ➡️, ⚪️➡️ 🏧 🧾 ⚙️), ⚒ 🔢 include_in_schema Query False:

=== "🐍 3️⃣.6️⃣ & 🔛"

```Python hl_lines="10"
{!> ../../../docs_src/query_params_str_validations/tutorial014.py!}
```

=== "🐍 3️⃣.1️⃣0️⃣ & 🔛"

```Python hl_lines="8"
{!> ../../../docs_src/query_params_str_validations/tutorial014_py310.py!}
```

🌃

👆 💪 📣 🌖 🔬 & 🗃 👆 🔢.

💊 🔬 & 🗃:

• alias
• title
• description
• deprecated

🔬 🎯 🎻:

• min_length
• max_length
• regex

👫 🖼 👆 👀 ❔ 📣 🔬 str 💲.

👀 ⏭ 📃 👀 ❔ 📣 🔬 🎏 🆎, 💖 🔢.