landing-page-plugs

name	landing_page-plugs
description	Custom Plug middleware patterns in landing_page_backend — authentication (JWT/Passport), authorization, permission checking, and rate limiting.
metadata	{"author":"Vũ Lưu","version":"2026.03.30","source":"Source code landing_page_backend"}

Landing Page — Plugs

Custom Plug middleware architecture for authentication, authorization, and permission control.

Core

Topic	Description	Reference
Authentication Plugs	JWT validation, Passport auth, Account lookup	core-auth
Permission Plugs	Role-based access control, page/org/team checks	core-permissions

Quick Reference

Authentication Pipeline

# Router pipeline — plugs chạy tuần tự
pipeline :passport do
  plug LandingPageWeb.Plug.PassportPlug     # 1. Validate token → assigns :token_claims
end

pipeline :account do
  plug LandingPageWeb.Plug.AccountPlug      # 2. Lookup account → assigns :account
end

pipeline :organization do
  plug LandingPageWeb.Plug.OrganizationPlug  # 3. Lookup org → assigns :organization
end

# Scope sử dụng pipelines
scope "/api/v1", LandingPageWeb.V1 do
  pipe_through [:api, :passport, :account, :organization]

  resources "/pages", PageController
end

Writing a Custom Plug

defmodule LandingPageWeb.Plug.MyCustomPlug do
  import Plug.Conn

  def init(opts), do: opts

  def call(conn, _opts) do
    # 1. Lấy data từ conn (headers, assigns, params)
    account = conn.assigns.account

    # 2. Validate/process
    case validate(account) do
      :ok ->
        # 3a. Success → assign data và pass conn tiếp
        conn |> assign(:validated, true)
      :error ->
        # 3b. Fail → halt pipeline
        conn |> send_resp(403, "Forbidden") |> halt()
    end
  end
end

Permission Check Plug

# Trong controller — chỉ áp dụng cho specific actions
plug LandingPageWeb.Plug.PermissionCheck,
     [role: :owner, type: :page]
     when action in [:delete]

plug LandingPageWeb.Plug.PermissionCheck,
     [role: :manager, type: :page]
     when action in [:page_detail, :update_right]

plug LandingPageWeb.Plug.PermissionCheck,
     [role: :organization_admin, type: :organization]
     when action in [:bulk_update_rights]