Forum and Chat Backend API Documentation

This README provides an overview of the available endpoints, their purposes, request/response formats, and notes on authentication. This API is built with Go, uses a SQLite database, and provides endpoints for user registration, login, posts, comments, and private messages.

Base URL

All endpoints are served from:

http://localhost:8080

Authentication

• Some endpoints require an authenticated session.
• Authentication is performed via a session_token cookie that is set when you log in.
• After logging in, include the session_token cookie on subsequent requests.

Endpoints

Registration

POST /api/register

Description: Registers a new user.

Request Body (JSON):

{
  "nickname": "string",
  "email": "string",
  "password": "string",
  "age": 25,
  "gender": "M",
  "first_name": "string",
  "last_name": "string"
}

Response:

• 200 OK on success.
• 400 Bad Request if validation fails or user already exists.

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Login

POST /api/login

Description: Logs an existing user in using either their nickname or email, and password. Sets a session_token cookie on success.

Request Body (JSON):

{
  "identifier": "nickname_or_email",
  "password": "string"
}

Response:

• 200 OK on success (with Set-Cookie: session_token=<token>).
• 401 Unauthorized if credentials are invalid.

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Logout

GET /api/logout

Description: Logs out the current user by clearing the session cookie.

Authentication: Required (session_token cookie).

Response:

• 200 OK on success.

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Create Post

POST /api/create_post

Description: Creates a new post in the forum.

Authentication: Required.

Request Body (JSON):

{
  "category": "string",
  "title": "string",
  "content": "string"
}

Response:

• 200 OK on success.
• 401 Unauthorized if not logged in.

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Get Posts

GET /api/posts

Description: Retrieves a list of all posts (public feed).

Authentication: Not strictly required (depends on your final logic).

Response (JSON):

[
  {
    "id": "string",
    "user_id": "string",
    "category": "string",
    "title": "string",
    "content": "string",
    "created_at": "timestamp",
    "user_name": "string"
  }
]

• 200 OK on success.

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Create Comment

POST /api/create_comment?post_id=<POST_ID>

Description: Adds a new comment to a specific post.

Authentication: Required.

Request Body (JSON):

{
  "content": "string"
}

Response:

• 200 OK on success.
• 400 Bad Request if post_id is missing or invalid.
• 401 Unauthorized if not logged in.

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Get Comments

GET /api/comments?post_id=<POST_ID>

Description: Retrieves all comments for a given post.

Response (JSON):

[
  {
    "id": "string",
    "post_id": "string",
    "user_id": "string",
    "content": "string",
    "created_at": "timestamp",
    "user_name": "string"
  }
]

• 200 OK on success.
• 400 Bad Request if post_id is missing or invalid.

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Get Messages (Private Chat History)

GET /api/get_messages?user_id=<OTHER_USER_ID>&limit=10&offset=0

Description: Fetches the private messages between the currently logged-in user and another user. Supports pagination via limit and offset query parameters.

Authentication: Required.

Response (JSON):

[
  {
    "id": "string",
    "sender_id": "string",
    "receiver_id": "string",
    "content": "string",
    "created_at": "timestamp",
    "sender_name": "string"
  }
]

• 200 OK on success.
• 401 Unauthorized if not logged in.

---

Users List

GET /api/users_list

Description: Retrieves a list of all registered users. Useful for showing who might be available to chat.

Authentication: Required.

Response (JSON):

[
  {
    "ID": "string",
    "Nickname": "string",
    "Email": "string",
    "Password": "hashed_string",
    "Age": 25,
    "Gender": "string",
    "FirstName": "string",
    "LastName": "string"
  }
]

• 200 OK on success.
• 401 Unauthorized if not logged in.

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WebSocket Endpoint

URL: ws://localhost:8080/ws

Description:
Used for real-time private messaging. Once authenticated (the server checks the session_token), you can send and receive JSON messages of the form:

Message Format (JSON):

{
  "type": "private_message",
  "content": "string",
  "receiver_id": "string",
  "sender_id": "string",
  "sender_name": "string"
}

Behavior:

• Sending a message through this WebSocket broadcasts it to the recipient if they are online.
• The message is also stored in the database.
• If the recipient is not online, the message is simply stored and will be available when they connect again and load the chat history.

Notes:

• Ensure you have a valid session_token before attempting to connect.
• The frontend (like the SPA) is expected to connect using the browser’s WebSocket API and attach the session cookie automatically.

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Error Responses

• 400 Bad Request: Usually due to invalid input, missing parameters, or duplicate entries.
• 401 Unauthorized: The user is not authenticated or the session has expired.
• 500 Internal Server Error: Unexpected server errors.

In all cases, error responses will typically be accompanied by a textual message describing the issue.

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Testing

You can test the endpoints using a tool like Thunder Client or Postman. For WebSockets, use a browser console, a custom frontend, or a tool like wscat (with modifications to include authentication).

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This README provides an overview of the key endpoints and their usage. For full details, refer to the source code and implement the frontend as needed.