Fetches the LiveView and merges with the controller flash.

Replaces the default :fetch_flash plug used by Phoenix.Router.

Examples

defmodule MyAppWeb.Router do
  use LiveGenWeb, :router
  import Phoenix.LiveView.Router

  pipeline :browser do
    ...
    plug :fetch_live_flash
  end
  ...
end

Defines a LiveView route.

A LiveView can be routed to by using the live macro with a path and the name of the LiveView:

live "/thermostat", ThermostatLive

By default, you can generate a route to this LiveView by using the live_path helper:

live_path(@socket, ThermostatLive)

HTTP requests

The HTTP request method that a route defined by the live/4 macro responds to is GET.

Actions and live navigation

It is common for a LiveView to have multiple states and multiple URLs. For example, you can have a single LiveView that lists all articles on your web app. For each article there is an "Edit" button which, when pressed, opens up a modal on the same page to edit the article. It is a best practice to use live navigation in those cases, so when you click edit, the URL changes to "/articles/1/edit", even though you are still within the same LiveView. Similarly, you may also want to show a "New" button, which opens up the modal to create new entries, and you want this to be reflected in the URL as "/articles/new".

In order to make it easier to recognize the current "action" your LiveView is on, you can pass the action option when defining LiveViews too:

live "/articles", ArticleLive.Index, :index
live "/articles/new", ArticleLive.Index, :new
live "/articles/:id/edit", ArticleLive.Index, :edit

When an action is given, the generated route helpers are named after the LiveView itself (in the same way as for a controller). For the example above, we will have:

article_index_path(@socket, :index)
article_index_path(@socket, :new)
article_index_path(@socket, :edit, 123)

The current action will always be available inside the LiveView as the @live_action assign, that can be used to render a LiveComponent:

<.live_component :if={@live_action == :new} module={MyAppWeb.ArticleLive.FormComponent} id="form" />

Or can be used to show or hide parts of the template:

{if @live_action == :edit, do: render("form.html", user: @user)}

Note that @live_action will be nil if no action is given on the route definition.

Options

• :container - an optional tuple for the HTML tag and DOM attributes to be used for the LiveView container. For example: {:li, style: "color: blue;"}. See Phoenix.Component.live_render/3 for more information and examples.

• :as - optionally configures the named helper. Defaults to :live when using a LiveView without actions or defaults to the LiveView name when using actions.

• :metadata - a map to optional feed metadata used on telemetry events and route info, for example: %{route_name: :foo, access: :user}. This data can be retrieved by calling Phoenix.Router.route_info/4 with the uri from the handle_params callback. This can be used to customize a LiveView which may be invoked from different routes.

• :private - an optional map of private data to put in the plug connection, for example: %{route_name: :foo, access: :user}. The data will be available inside conn.private in plug functions.

Examples

defmodule MyApp.Router
  use Phoenix.Router
  import Phoenix.LiveView.Router

  scope "/", MyApp do
    pipe_through [:browser]

    live "/thermostat", ThermostatLive
    live "/clock", ClockLive
    live "/dashboard", DashboardLive, container: {:main, class: "row"}
  end
end

iex> MyApp.Router.Helpers.live_path(MyApp.Endpoint, MyApp.ThermostatLive)
"/thermostat"

Defines a live session for live redirects within a group of live routes.

live_session/3 allow routes defined with live/4 to support navigate redirects from the client with navigation purely over the existing websocket connection. This allows live routes defined in the router to mount a new root LiveView without additional HTTP requests to the server. For backwards compatibility reasons, all live routes defined outside of any live session are considered part of a single unnamed live session.

Security Considerations

In a regular web application, we perform authentication and authorization checks on every request. Given LiveViews start as a regular HTTP request, they share the authentication logic with regular requests through plugs. Once the user is authenticated, we typically validate the sessions on the mount callback. Authorization rules generally happen on mount (for instance, is the user allowed to see this page?) and also on handle_event (is the user allowed to delete this item?). Performing authorization on mount is important because navigates do not go through the plug pipeline.

live_session can be used to draw boundaries between groups of LiveViews. Redirecting between live_sessions will always force a full page reload and establish a brand new LiveView connection. This is useful when LiveViews require different authentication strategies or simply when they use different root layouts (as the root layout is not updated between live redirects).

Please read our guide on the security model for a detailed description and general tips on authentication, authorization, and more.

live_session and forward

live_session does not currently work with forward. LiveView expects your live routes to always be directly defined within the main router of your application.

live_session and scope

Aliases set with Phoenix.Router.scope/2 are not expanded in live_session arguments. You must use the full module name instead.

Options

• :session - An optional extra session map or MFA tuple to be merged with the LiveView session. For example, %{"admin" => true} or {MyMod, :session, []}. For MFA, the function is invoked and the Plug.Conn struct is prepended to the arguments list.

• :root_layout - An optional root layout tuple for the initial HTTP render to override any existing root layout set in the router.

• :on_mount - An optional list of hooks to attach to the mount lifecycle of each LiveView in the session. See Phoenix.LiveView.on_mount/1. Passing a single value is also accepted.

• :layout - An optional layout the LiveView will be rendered in. Setting this option overrides the layout via use Phoenix.LiveView. This option may be overridden inside a LiveView by returning {:ok, socket, layout: ...} from the mount callback

Examples

scope "/", MyAppWeb do
  pipe_through :browser

  live_session :default do
    live "/feed", FeedLive, :index
    live "/status", StatusLive, :index
    live "/status/:id", StatusLive, :show
  end

  live_session :admin, on_mount: MyAppWeb.AdminLiveAuth do
    live "/admin", AdminDashboardLive, :index
    live "/admin/posts", AdminPostLive, :index
  end
end

In the example above, we have two live sessions. Live navigation between live views in the different sessions is not possible and will always require a full page reload. This is important in the example above because the :admin live session has authentication requirements, defined by on_mount: MyAppWeb.AdminLiveAuth, that the other LiveViews do not have.

If you have both regular HTTP routes (via get, post, etc) and live routes, then you need to perform the same authentication and authorization rules in both. For example, if you were to add a get "/admin/health" entry point inside the :admin live session above, then you must create your own plug that performs the same authentication and authorization rules as MyAppWeb.AdminLiveAuth, and then pipe through it:

live_session :admin, on_mount: MyAppWeb.AdminLiveAuth do
  scope "/" do
    # Regular routes
    pipe_through [MyAppWeb.AdminPlugAuth]
    get "/admin/health", AdminHealthController, :index

    # Live routes
    live "/admin", AdminDashboardLive, :index
    live "/admin/posts", AdminPostLive, :index
  end
end

The opposite is also true, if you have regular http routes and you want to add your own live routes, the same authentication and authorization checks executed by the plugs listed in pipe_through must be ported to LiveViews and be executed via on_mount hooks.