認証と認可
システムリソースへのアクセスを制御する、堅牢な認証と認可の仕組みを実装します。
「認証と認可」はCoddyKit上の無料System Design Basics for Backend Developersレッスンです。 これはレッスン1/4です。 下記で完全なレッスンを無料で読むことができます。その後、ブラウザ内の組み込みコードエディタと24時間対応のAIチューターでハンズオン演習できます。 これはSystem Design Basics for Backend Developers学習パスの一部であり、ウェブとCoddyKitアプリ全体で進捗が同期されます。 System Design Basics for Backend Developersコースには全4レッスンが含まれています。
このレッスンの一部はまだ翻訳されておらず、英語で表示されています。
Auth vs. Auth: The Basics
In system design, authentication and authorization are critical for security. They control who can access your system and what they can do.
- Authentication (AuthN) verifies who you are.
- Authorization (AuthZ) determines what you're allowed to do.
Think of it like a club: authentication is checking your ID at the door, authorization is seeing if you have a VIP pass to enter special areas.
What is Authentication?
Authentication is the process of proving your identity to a system. This confirms that you are who you claim to be.
Common authentication methods include:
- Password-based: Username and password.
- Multi-factor: Combining passwords with codes from an app or SMS.
- Biometric: Fingerprints or facial recognition.
- Token-based: Using a cryptographic token after initial login.
Token-Based Authentication
Token-based authentication is popular for web and mobile apps. After a user logs in (authenticates) with credentials, the server issues a token.
This token is then sent with every subsequent request to prove the user's identity without sending credentials repeatedly. A common type is the JSON Web Token (JWT).
Understanding JWTs
A JWT (JSON Web Token) is a compact, URL-safe means of representing claims to be transferred between two parties. It's often used to authenticate users.
JWTs consist of three parts, separated by dots:
- Header: Type of token and signing algorithm.
- Payload: Claims (user ID, roles, expiration).
- Signature: Used to verify the token hasn't been tampered with.
It looks something like this:
eyJhbGciOiJIUzI1NiJ9.eyJ1c2VySWQiOiIxMjMiLCJyb2xlIjoiYWRtaW4ifQ.SFLS...Simple Token Check Demo
When a client sends a request with a token, the server must validate it. This often involves checking the signature and expiration.
Here's a very simplified conceptual example of how a server might check if a token is known, representing a basic validation step:
public class TokenChecker {
public static void main(String[] args) {
String userToken = "validUserToken123";
String adminToken = "adminSecretToken456";
String invalidToken = "badToken";
System.out.println("User Token Check: " + isValid(userToken));
System.out.println("Admin Token Check: " + isValid(adminToken));
System.out.println("Invalid Token Check: " + isValid(invalidToken));
}
// A very simplified conceptual token validation
public static boolean isValid(String token) {
if (token.equals("validUserToken123") || token.equals("adminSecretToken456")) {
return true; // Token is conceptually 'valid'
}
return false; // Token is not recognized
}
}What is Authorization?
Authorization is the process of determining what an authenticated user or system is permitted to do.
For example, a regular user might be able to view their own profile, but only an administrator can delete user accounts. Authorization answers the question: "Are you allowed to do that?"
Role-Based Access Control (RBAC)
One common authorization model is Role-Based Access Control (RBAC). In RBAC, permissions are associated with roles, and users are assigned to roles.
- Users: Individuals or systems.
- Roles: Collections of permissions (e.g., 'Admin', 'Editor', 'Viewer').
- Permissions: Specific actions on resources (e.g., 'read_post', 'edit_user').
This simplifies managing access, as you assign users to roles rather than individual permissions.
Policy-Based Authorization
For more complex scenarios, Policy-Based Authorization (like Attribute-Based Access Control or ABAC) allows for very fine-grained control.
Instead of just roles, access decisions are based on attributes of the user, the resource, the environment, and the action itself. This offers greater flexibility but can be more complex to manage.
AuthN and AuthZ Together
Authentication and authorization work hand-in-hand in a typical request flow:
- A user tries to access a resource.
- The system authenticates the user (e.g., validates their token). If invalid, access is denied.
- If authenticated, the system then authorizes the user: it checks if the user's role or attributes grant them permission for that specific action on that resource.
- If authorized, access is granted. Otherwise, it's denied.
Identify the Concepts
Which of the following statements correctly describe the concepts of Authentication and Authorization?
Recap: Securing Access
We've explored the crucial difference between authentication (who you are) and authorization (what you can do).
You learned about token-based authentication with JWTs and authorization models like RBAC. Understanding these concepts is fundamental to designing secure and robust systems.
Keep practicing these distinctions as you design systems that need to control access effectively!
よくある質問
「認証と認可」レッスンは無料ですか？
はい。「認証と認可」の完全なテキストはこのウェブで無料で読めます。インタラクティブに演習し（組み込みコードエディタと24時間対応のAIチューター）、System Design Basics for Backend Developersコースの残りをアンロックするには、CoddyKit PROにアップグレードしてください。 System Design Basics for Backend Developersコースには全4レッスンが含まれています。
「認証と認可」で何を学びますか？
システムリソースへのアクセスを制御する、堅牢な認証と認可の仕組みを実装します。 ブラウザで直接実行するハンズオンコードでSystem Design Basics for Backend Developersを演習し、24時間対応のAIチューターがレッスンを進める中での質問に答えます。
System Design Basics for Backend Developersを始めるのに経験は必要ですか？
事前経験は必要ありません。CoddyKitのSystem Design Basics for Backend Developersは初級者から上級者向けに構成されているため、ここから始めるか最初から始めて、自分のペースで進むことができます。 これはレッスン1/4です。
「認証と認可」レッスンにはどのくらい時間がかかりますか？
ほとんどのCoddyKitレッスンは約5～10分かかります。各レッスンはコンパクトでインタラクティブなので、着実に進歩し、ウェブとアプリ全体で正確に前回の場所から再開できます。
このSystem Design Basics for Backend Developersレッスンでコードを書いて実行できますか？
はい。すべてのSystem Design Basics for Backend Developersレッスンに組み込みコードエディタが含まれているため、ブラウザでリアルコードを書いて実行し、即座のAIフィードバックを取得できます。ローカル設定は不要です。