Routing System

Nex’s routing system follows the principle of “file-as-router,” allowing you to organize your application URLs intuitively through directory structure.

1. Static Routes

The simplest form of routing is direct mapping.

src/pages/index.ex -> /
src/pages/about.ex -> /about
src/pages/contact/index.ex -> /contact
src/pages/blog/list.ex -> /blog/list

2. Dynamic Routes `[id]`

When you need to capture parameters in a URL, use the square bracket syntax for filenames.

src/pages/users/[id].ex -> /users/123 (params: id="123")
src/pages/posts/[slug].ex -> /posts/hello-nex (params: slug="hello-nex")

Accessing parameters in code:

defmodule MyApp.Pages.Users.Id do
  use Nex
  
  def mount(%{"id" => id}) do
    # id will be "123"
    %{user: find_user(id)}
  end
end

3. Catch-All Routes `[...path]`

If you need to capture all remaining path segments, use the [...name] syntax.

src/pages/docs/[...path].ex -> /docs/intro/getting-started (params: path=["intro", "getting-started"])

4. Parameter Priority

When multiple sources have parameters with the same name, Nex follows this priority (former overrides latter):

Path Parameters: e.g., id in /users/[id].
Query Parameters: e.g., q in /search?q=nex.

5. Route Matching Rules

When a URL matches multiple possible route files, Nex sorts them by priority:

Exact Static Match over Dynamic Parameter Match.
Fewer Dynamic Parameters first.
Non-Catch-All over Catch-All.
Longer Path first.

Example: Visiting /users/new

If src/pages/users/new.ex exists, it will take priority over src/pages/users/[id].ex.