如何在phoenix elixir聊天应用程序的监督树中运行Redix并从其他模块访问

Question

I want to use {:redix, "~> 0.6.1"} hex package to my chat application and start in supervision tree

{:ok, conn} = Redix.start_link()
{:ok, conn} = Redix.start_link(host: "example.com", port: 5000)
{:ok, conn} = Redix.start_link("redis://localhost:6379/3", name: :redix)


Redix.command(conn, ["SET", "mykey", "foo"])

but it gives error when I try to put connection start link to child process

children = [
      # Start the Ecto repository
      supervisor(PhoenixChat.Repo, []),
      # Start the endpoint when the application starts
      supervisor(PhoenixChat.Endpoint, []),
      # Start your own worker by calling: PhoenixChat.Worker.start_link(arg1, arg2, arg3)
      # worker(PhoenixChat.Worker, [arg1, arg2, arg3]),
      supervisor(PhoenixChat.Presence, []),

      #supervisor(Phoenix.PubSub.Redis, [:chat_pubsub, host: "127.0.0.1"])
    ]

How can I start redix connection and store data to Redis?

Answer 1

What you want to do is Register process id. To do that you can usually specify its name in opts, like this:

worker(Redix, [[], [name: RedixConnection]])

When the process is registered usually you can use it's name instead of PID (always check in documentation, but that is common pattern) like this:

Redix.command(RedixConnection, ["PING"])

Most of the time one connection isn't enough. You probably want to use some kind of pooling mechanism like poolboy . There is very neat page in documentation for you to read which is called Real-world usage . It will probably answer most of the questions related to this topic.

Please also consider using Erlang/Elixir built in solutions for your cause. I don't know your exact use case but you may want to check out ETS, DTS and Mnesia.

Answer 2

  children = [
      # Start the Ecto repository
      supervisor(PhoenixChat.Repo, []),
      # Start the endpoint when the application starts
      supervisor(PhoenixChat.Endpoint, []),
      # Start your own worker by calling: PhoenixChat.Worker.start_link(arg1, arg2, arg3)
      # worker(PhoenixChat.Worker, [arg1, arg2, arg3]),
      supervisor(PhoenixChat.Presence, []),
      worker(Redix, [[], [name: :redix]]),

      #supervisor(Phoenix.PubSub.Redis, [:chat_pubsub, host: "127.0.0.1"])
    ]




Redix.command(:redix, ["SET", "key", "value"])