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Phoenix 1.4.x to 1.5.0 upgrade instructions

Phoenix 1.5 requires Elixir >= 1.7. Be sure your existing version is up to date by running elixir -v on the command line.

Install the new project generator

$ mix archive.uninstall phx_new
$ mix archive.install hex phx_new 1.5.0

Bump your deps

Update your Phoenix and Phoenix PubSub deps to their latest versions.

Note: The outdated Phoenix.Endpoint.CowboyAdapter for Cowboy 1 is deprecated. Please make sure {:plug_cowboy, "~> 2.1"} is specified in your deps.

  defp deps do
      {:phoenix, "~> 1.5.0"},
      {:phoenix_pubsub, "~> 2.0"},
      {:plug_cowboy, "~> 2.1"},

PubSub 2.0 Changes

Phoenix.PubSub 2.0 provides a simpler, more extensible, and more performant Phoenix.PubSub API. For users of Phoenix.PubSub, the API is the same, but the pubsub server being started by the endpoint has been deprecated in favor of starting the PubSub server yourself. This prevents race conditions on startup and decouples the PubSub system from the endpoint.

First, replace your endpoint's :pubsub config with a new :pubsub_server key in config/config.exs:

config :my_app, MyApp.Endpoint,
  url: [host: "localhost"],
- pubsub: [name: MyApp.PubSub, adapter: Phoenix.PubSub.PG2],
+ pubsub_server: MyApp.PubSub,

Next, update your lib/my_app/application.ex supervision tree to start its own PubSub:

children = [
+ # Start the PubSub system
+ {Phoenix.PubSub, name: MyApp.PubSub},
  # Start the Endpoint (http/https)

Update your layouts

Rendering the child template from layouts is deprecated. Replace:

<%= render(@view_module, @view_template, assigns) %>

With the new @inner_content assign:

<%= @inner_content %>

Update your Tests

Using Phoenix.ConnTest is deprecated, replace usage:

use Phoenix.ConnTest


import Plug.Conn
import Phoenix.ConnTest

Note: for most applications, this will be located in a single place in test/support/conn_case.ex

Add the new Phoenix LiveDashboard (optional)

The new LiveDashboard project provides real-time performance monitoring and debugging tools for Phoenix developers. Follow the steps in the project readme to include it in your existing applications

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