- データの検証:
  - データが無効な場合に自動でエラーをクリアします。
  - 深い入れ子になった JSON オブジェクトでも検証が可能です。
- 入力データの<abbr title="also known as: serialization, parsing, marshalling">変換</abbr>: ネットワークから Python のデータや型に変換してから読み取ります:
  - JSON.
  - パスパラメータ
  - クエリパラメータ
  - クッキー
  - ヘッダー
  - フォーム
  - ファイル
- 出力データの<abbr title="also known as: serialization, parsing, marshalling">変換</abbr>: Python のデータや型からネットワークデータへ変換します (JSON として):

# 🔗

**FastAPI** ✔️ 📶 🏋️ ✋️ 🏋️ **<abbr title="also known as components, resources, providers, services, injectables">🔗 💉</abbr>** ⚙️.

⚫️ 🏗 📶 🙅 ⚙️, &amp; ⚒ ⚫️ 📶 ⏩ 🙆 👩‍💻 🛠️ 🎏 🦲 ⏮️ **FastAPI**.

## ⚫️❔ "🔗 💉"

**"🔗 💉"** ⛓, 📋, 👈 📤 🌌 👆 📟 (👉 💼, 👆 *➡ 🛠️ 🔢*) 📣 👜 👈 ⚫️ 🚚 👷 &amp; ⚙️: "🔗".

&amp; ⤴️, 👈 ⚙️ (👉 💼 **FastAPI**) 🔜 ✊ 💅 🔨 ⚫️❔ 💪 🚚 👆 📟 ⏮️ 📚 💪 🔗 ("💉" 🔗).

👉 📶 ⚠ 🕐❔ 👆 💪:

# Dependencies

**FastAPI** has a very powerful but intuitive **<abbr title="also known as components, resources, providers, services, injectables">Dependency Injection</abbr>** system.

It is designed to be very simple to use, and to make it very easy for any developer to integrate other components with **FastAPI**.

## What is "Dependency Injection"

    * Aṣiṣe alaifọwọyi/aládàáṣiṣẹ́ àti aṣiṣe ti ó hàn kedere nígbàtí àwọn àkójọf'áyẹ̀wò (i.e. data) kò wulo tabi tí kò fẹsẹ̀ múlẹ̀.
    * Ìfọwọ́sí fún ohun elo JSON tí ó jìn gan-an.
* <abbr title="also known as: serialization, parsing, marshalling">Ìyípadà</abbr> tí input àkójọf'áyẹ̀wò: tí ó wà láti nẹtiwọọki si àkójọf'áyẹ̀wò àti irúfẹ́ àmì ìtọ́kasí Python. Ó ń ka láti:
    * JSON.
    * èròjà ọ̀nà tí ò gbé gbà.
    * èròjà ìbéèrè.

    * Validation even for deeply nested JSON objects.
* <abbr title="also known as: serialization, parsing, marshalling">Conversion</abbr> of input data: coming from the network to Python data and types. Reading from:
    * JSON.
    * Path parameters.
    * Query parameters.
    * Cookies.
    * Headers.
    * Forms.
    * Files.

    * 🛠️.
    * 🆎 ✅.
* 🔬 💽:
    * 🏧 & 🆑 ❌ 🕐❔ 📊 ❌.
    * 🔬 🙇 🐦 🎻 🎚.
* <abbr title="also known as: serialization, parsing, marshalling">🛠️</abbr> 🔢 💽: 👟 ⚪️➡️ 🕸 🐍 💽 &amp; 🆎. 👂 ⚪️➡️:
    * 🎻.
    * ➡ 🔢.
    * 🔢 🔢.
    * 🍪.
    * 🎚.
    * 📨.
    * 📁.
* <abbr title="also known as: serialization, parsing, marshalling">🛠️</abbr> 🔢 📊: 🗜 ⚪️➡️ 🐍 💽 &amp; 🆎 🕸 💽 (🎻):

So, it was a complete additional system.

It is not very popular or used nowadays.

## OpenAPI

OpenAPI (previously known as Swagger) is the open specification for building APIs (now part of the Linux Foundation).

**FastAPI** is based on **OpenAPI**.

This means that you can send only the data that you want to update, leaving the rest intact.

!!! note
    `PATCH` is less commonly used and known than `PUT`.

    And many teams use only `PUT`, even for partial updates.

    You are **free** to use them however you want, **FastAPI** doesn't impose any restrictions.

    * Validation even for deeply nested JSON objects.
* <abbr title="also known as: serialization, parsing, marshalling">Conversion</abbr> of input data: coming from the network to Python data and types. Reading from:
    * JSON.
    * Path parameters.
    * Query parameters.
    * Cookies.
    * Headers.
    * Forms.
    * Files.

But a variable like `user-agent` is invalid in Python.

So, by default, `Header` will convert the parameter names characters from underscore (`_`) to hyphen (`-`) to extract and document the headers.

Also, HTTP headers are case-insensitive, so, you can declare them with standard Python style (also known as "snake_case").