phoenix

Phoenix Framework Skill - Quick Reference

Version: 1.0.0 | Last Updated: 2025-10-22 | Agent: backend-developer

Quick reference for Phoenix and Elixir development patterns. For comprehensive documentation, see REFERENCE.md.

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Table of Contents

1. Phoenix API Development
2. OTP Patterns
3. Phoenix LiveView
4. Ecto Database Operations
5. Phoenix Channels
6. Background Jobs (Oban)
7. Production Deployment
8. Testing with ExUnit
9. Security Best Practices
10. Performance Optimization

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Phoenix API Development

RESTful Controller Pattern

defmodule MyAppWeb.PostController do
  use MyAppWeb, :controller
  alias MyApp.Blog
  alias MyApp.Blog.Post

  # List all posts
  def index(conn, _params) do
    posts = Blog.list_posts()
    render(conn, "index.json", posts: posts)
  end

  # Show single post
  def show(conn, %{"id" => id}) do
    post = Blog.get_post!(id)
    render(conn, "show.json", post: post)
  end

  # Create post
  def create(conn, %{"post" => post_params}) do
    case Blog.create_post(post_params) do
      {:ok, post} ->
        conn
        |> put_status(:created)
        |> render("show.json", post: post)
      {:error, changeset} ->
        conn
        |> put_status(:unprocessable_entity)
        |> render("error.json", changeset: changeset)
    end
  end

  # Update post
  def update(conn, %{"id" => id, "post" => post_params}) do
    post = Blog.get_post!(id)
    case Blog.update_post(post, post_params) do
      {:ok, updated_post} ->
        render(conn, "show.json", post: updated_post)
      {:error, changeset} ->
        conn
        |> put_status(:unprocessable_entity)
        |> render("error.json", changeset: changeset)
    end
  end

  # Delete post
  def delete(conn, %{"id" => id}) do
    post = Blog.get_post!(id)
    {:ok, _post} = Blog.delete_post(post)
    send_resp(conn, :no_content, "")
  end
end