Help with supervisors

Phoenix Forum Questions / Help
1

hello i am having a problem with creating supervisors, basically i want a sup to run in a loop until killed im trying to emulate live customers hitting my site and pushing random data to the channel and endpoints i get an error what am i doing wrong thanks

** (EXIT from #PID<0.643.0>) shutdown: failed to start child: Bot.Customer
    ** (EXIT) an exception was raised:
        ** (UndefinedFunctionError) function Bot.Customer.start_link/1 is undefined or private. Did you mean one of:

      * start_link/0

            (broker) Bot.Customer.start_link(Bot.Customer)
            (stdlib) supervisor.erl:365: :supervisor.do_start_child/2
            (stdlib) supervisor.erl:348: :supervisor.start_children/3
            (stdlib) supervisor.erl:314: :supervisor.init_children/2
            (stdlib) gen_server.erl:328: :gen_server.init_it/6
            (stdlib) proc_lib.erl:247: :proc_lib.init_p_do_apply/3

lib/bot/supervisor.ex

defmodule Bot.Supervisor do
  use Supervisor

    def start_link do
      Supervisor.start_link(__MODULE__, :ok)
    end

  def init(:ok) do
    children = [
      worker(Bot.Customer, [Bot.Customer])
    ]
IO.inspect(children, label: "supervisor children")
    supervise(children, strategy: :one_for_one)
  end
end

defmodule Bot.Customer do
use GenServer

def generate() do

  uuid = UUID.uuid1()

  citys = ["Peoria","Glendale", "Tucson"]
  states = ["AZ","NM","TX"]
  zips = ["85711","85008","85710"]
  streets = ["West Peoria Avenue","East Peoria Avenue","North Erlang Avenue", "West Elixir Blvd"]

   :random.seed(:erlang.now)

   faddress = Enum.random(5200..150000)
   fcity = Enum.random(citys)
   fstate = Enum.random(states)
   fzip = Enum.random(zips)
   fstreet = Enum.random(streets)

   :random.seed(:erlang.now)

   taddress = Enum.random(5200..150000)
   tcity = Enum.random(citys)
   tstate = Enum.random(states)
   tzip = Enum.random(zips)
   tstreet = Enum.random(streets)

  from = to_string(faddress) <> " " <> to_string(fstreet) <> ", " <> to_string(fcity) <> ", " <> to_string(fstate) <>", United States"
  to =  to_string(taddress) <> " " <> to_string(tstreet) <> ", " <> to_string(tcity) <> ", " <> to_string(tstate) <>", United States"

  %{from: from, to: to }

  ## connect to channels tbd
  ## store to  db tbd

end

@doc """
Starts the registry with the given `name`.
"""

 def start_link() do
   GenServer.start_link(__MODULE__, :ok)
 end

  def handle_call({:get, slug}, _from, state) do

  end

  def handle_call({:set, slug, value}, _from, state) do

  end

  def init(args) do

  end

end
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2

The error message here is actually very useful:

It tells you that your Supervisor is trying to call Bot.Customer.start_link/1 when you have only defined Bot.customer.start_link/0.

The supervisor uses the list which is the second argument of the worker call as parameters to the worker’s start_link function. So you’re passing your worker one argument which currently is its module name while you seem to be expecting no argument.

If you are unfamiliar with how to use Supervisors in Elixir, I highly recommend this brief video presentation:

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