Phoenix LiveView Action Requests Demo

A demonstration of how Phoenix LiveView can replace complex multi-framework stacks (Django + React, Rails + React, etc.) with a single, elegant solution for building interactive, real-time data tables.

What This Demo Shows

This project implements a fully-featured data table with filtering, sorting, and pagination in a fraction of the code required by traditional stack combinations. What typically requires:

• Backend API (Django/Rails)
• Frontend framework (React/Vue)
• State management (Redux/Zustand)
• API client libraries (Axios/Fetch)
• TypeScript type definitions
• Multiple build tools and configs

...is accomplished here in one Phoenix LiveView module with progressive enhancement, real-time updates, and URL-based state management built in.

Why This Matters

Compared to Django + React (or similar stacks):

Aspect	Django + React	Phoenix LiveView
Codebase	Split across backend/frontend	Single unified codebase
Languages	Python + JavaScript/TypeScript	Elixir
Files needed	Views, serializers, API endpoints, React components, state management, type definitions	1 LiveView module + 1 context
State sync	Manual API calls, polling, or WebSocket setup	Automatic via LiveView
Real-time	Requires channels/WebSockets setup	Built-in
Progressive enhancement	Requires separate server-side rendering setup	Native
URL state	Manual query param handling on both ends	Declarative with handle_params/3
Deployment	Two separate services	Single Elixir application
Build complexity	Webpack/Vite + Python packaging	Mix (built-in)

Performance Benefits

• Reduced latency: No API round-trips, server renders diffs only
• Minimal bandwidth: LiveView sends HTML diffs, not full JSON payloads
• Efficient updates: Only changed DOM elements are updated
• No client-side state bugs: Source of truth lives on the server

Maintainability Benefits

• Single mental model: No context switching between languages/frameworks
• Fewer dependencies: No npm packages, no frontend framework updates
• Type safety: Elixir's pattern matching catches errors at compile time
• Simpler testing: Test the LiveView, not API + frontend + integration

Features Implemented

Core Functionality

• ✅ Search/Filter: Fuzzy text search on patient names
• ✅ Status Filter: Dropdown (All, Resolved, Unresolved)
• ✅ Assignment Filter: Dropdown (All, Mine, Assigned, Unassigned)
• ✅ Sorting: All columns with ascending/descending indicators
• ✅ Pagination: 25 records per page with full navigation
• ✅ URL State: All filters/sorting/pagination in URL (bookmarkable/shareable)
• ✅ Progressive Enhancement: Works with and without JavaScript

Technical Highlights

• Single LiveView module handles all user interactions
• Flop library for efficient query building
• SQLite database with proper indexes
• Real-time updates without polling or manual WebSocket setup
• Responsive design with Tailwind CSS + DaisyUI
• Theme support with light/dark modes

Database Schema

# action_requests table
id                    :binary_id, primary_key: true
patient_name          :string
status                :string
assigned_user_id      :integer
delivery_scheduled_at :naive_datetime
inserted_at           :utc_datetime
updated_at            :utc_datetime

# Indexes
- patient_name
- status
- assigned_user_id
- inserted_at

Tech Stack

• Phoenix 1.8+ - Web framework
• LiveView - Real-time server-rendered interactions
• Flop - Filtering, ordering, and pagination
• Ecto - Database wrapper and query builder
• SQLite - Embedded database (zero-config)
• Tailwind CSS + DaisyUI - Styling
• Elixir - Language

Getting Started

Prerequisites

• Elixir 1.15+
• Erlang/OTP 26+

Setup

# Install dependencies and setup database
mix setup

# Start the Phoenix server
mix phx.server

# Or start inside IEx
iex -S mix phx.server

Visit localhost:4000 in your browser.

Seeding Data

The database is automatically seeded with 1,000,000 sample records on first run. To reset:

mix ecto.reset

Code Structure

lib/
├── action_requests_demo/
│   ├── action_requests/
│   │   └── action_request.ex          # Schema definition
│   └── action_requests.ex             # Context with query logic
└── action_requests_demo_web/
    ├── live/
    │   └── action_requests_live.ex    # Main LiveView (filtering, sorting, pagination)
    └── router.ex                      # Single route

Progressive Enhancement

This app works perfectly without JavaScript:

1. Forms use method="get" and action="/"
2. Filter changes trigger full page reloads via form submission
3. All state persists in URL query parameters

When JavaScript is enabled:

1. Forms trigger LiveView events instead of page reloads
2. LiveView patches the URL and re-renders
3. Updates happen in real-time with minimal data transfer

The same code handles both modes via handle_params/3 - no duplicate logic required.

Testing

# Run all tests
mix test

# Run with coverage
mix test --cover

31 comprehensive tests covering all filtering, sorting, and pagination scenarios.

Key Implementation Details

Special Filter Logic

• "Mine": assigned_user_id = current_user_id (mocked as 1)
• "Assigned": assigned_user_id IS NOT NULL
• "Unassigned": assigned_user_id IS NULL

URL Format

All state is in the URL for bookmarking/sharing:

/?status=resolved&assignment=mine&patient_name=john&page=2&order_by=patient_name&order_directions=asc

Default Behavior

• Sort: inserted_at DESC (newest first)
• Per page: 25 records
• Current user: ID 1 (for demo purposes)

Why Elixir/Phoenix?

This demo showcases Elixir's strengths:

1. Concurrency: BEAM VM handles thousands of concurrent connections effortlessly
2. Fault tolerance: Process isolation means one user's error won't crash others
3. Low latency: LiveView's stateful connections eliminate API overhead
4. Developer productivity: Write less code, ship faster, maintain easier
5. Scalability: Vertical and horizontal scaling built into the platform

Production Considerations

This is a demo application. For production use, consider:

• Authentication/authorization (currently mocked)
• Rate limiting
• Database connection pooling configuration
• CDN for static assets
• Load balancing for multiple nodes
• Monitoring and observability

Learn More

• Phoenix Framework: https://www.phoenixframework.org/
• Phoenix LiveView: https://hexdocs.pm/phoenix_live_view
• Flop: https://hexdocs.pm/flop
• Elixir: https://elixir-lang.org/

License

This demonstration project is provided as-is for educational purposes.