Elixir 无法启动监控程序:(Protocol.UndefinedError)未为实现协议枚举
我正在尝试启动一个主管和一个GenServer:Elixir 无法启动监控程序:(Protocol.UndefinedError)未为实现协议枚举,elixir,otp,erlang-supervisor,gen-server,Elixir,Otp,Erlang Supervisor,Gen Server,我正在尝试启动一个主管和一个GenServer: defmodule SubscriptionManagerSupervisor do use Supervisor def start_link do Supervisor.start_link(__MODULE__, [], [{:name, __MODULE__}]) end # supervisor callback def init([]) do interval = 1000 childr
defmodule SubscriptionManagerSupervisor do
use Supervisor
def start_link do
Supervisor.start_link(__MODULE__, [], [{:name, __MODULE__}])
end
# supervisor callback
def init([]) do
interval = 1000
children = worker(SubscriptionManagerServer, [interval])
supervise(children, strategy: :one_for_one)
end
end
defmodule SubscriptionManagerServer do
use GenServer
import Logger
def start_link(interval) do
GenServer.start_link(__MODULE__, [interval])
end
def init(interval) do
state = :calendar.universal_time()
Logger.info "SubscriptionManagerServer init(). State: #{state} interval: #{interval}"
# This will send message to self on the interval. handle_info handles it.
:timer.send_interval(interval)
{:ok, state}
end
def handle_info(url, state) do
new_state = :calendar.universal_time()
Logger.info "SubscriptionManager handle_info(). new_state: #{new_state}"
{:noreply, new_state}
end
end
还有我的GenServer:
defmodule SubscriptionManagerSupervisor do
use Supervisor
def start_link do
Supervisor.start_link(__MODULE__, [], [{:name, __MODULE__}])
end
# supervisor callback
def init([]) do
interval = 1000
children = worker(SubscriptionManagerServer, [interval])
supervise(children, strategy: :one_for_one)
end
end
defmodule SubscriptionManagerServer do
use GenServer
import Logger
def start_link(interval) do
GenServer.start_link(__MODULE__, [interval])
end
def init(interval) do
state = :calendar.universal_time()
Logger.info "SubscriptionManagerServer init(). State: #{state} interval: #{interval}"
# This will send message to self on the interval. handle_info handles it.
:timer.send_interval(interval)
{:ok, state}
end
def handle_info(url, state) do
new_state = :calendar.universal_time()
Logger.info "SubscriptionManager handle_info(). new_state: #{new_state}"
{:noreply, new_state}
end
end
我尝试开始一切:
defmodule SubscriptionManagerApp do
use Application
import Logger
def start(_type, _args) do
Logger.info "Starting the SubscriptionManager."
SubscriptionManagerSupervisor.start_link()
end
end
但是,我收到以下错误:
** (Mix) Could not start application subscription_manager: SubscriptionManagerApp.start(:normal, []) returned an error: an exception was raised:
** c for {SubscriptionManagerServer, {SubscriptionManagerServer, :start_link, [1000]}, :permanent, 5000, :worker, [SubscriptionManagerServer]}
(elixir) lib/enum.ex:1: Enumerable.impl_for!/1
(elixir) lib/enum.ex:116: Enumerable.reduce/3
(elixir) lib/enum.ex:1636: Enum.reduce/3
(elixir) lib/enum.ex:1188: Enum.map/2
(elixir) lib/supervisor/spec.ex:169: Supervisor.Spec.supervise/2
(stdlib) supervisor.erl:294: :supervisor.init/1
(stdlib) gen_server.erl:328: :gen_server.init_it/6
(stdlib) proc_lib.erl:247: :proc_lib.init_p_do_apply/3
我试着改变了一些论点,仔细阅读了文档,但我被难住了 代码中有几个问题:
子项
需要是一个列表GenServer.start\u link
的第二个参数应该是interval
,而不是[interval]
inspect()
状态:计时器。发送间隔/1
,只有/2
和/3
@@ -8,7 +8,7 @@ defmodule SubscriptionManagerSupervisor do
# supervisor callback
def init([]) do
interval = 1000
- children = worker(SubscriptionManagerServer, [interval])
+ children = [worker(SubscriptionManagerServer, [interval])]
supervise(children, strategy: :one_for_one)
end
end
@@ -18,20 +18,20 @@ defmodule SubscriptionManagerServer do
import Logger
def start_link(interval) do
- GenServer.start_link(__MODULE__, [interval])
+ GenServer.start_link(__MODULE__, interval)
end
def init(interval) do
state = :calendar.universal_time()
- Logger.info "SubscriptionManagerServer init(). State: #{state} interval: #{interval}"
+ Logger.info "SubscriptionManagerServer init(). State: #{inspect(state)} interval: #{interval}"
# This will send message to self on the interval. handle_info handles it.
- :timer.send_interval(interval)
+ :timer.send_interval(interval, :tick)
{:ok, state}
end
def handle_info(url, state) do
new_state = :calendar.universal_time()
- Logger.info "SubscriptionManager handle_info(). new_state: #{new_state}"
+ Logger.info "SubscriptionManager handle_info(). new_state: #{inspect(new_state)}"
{:noreply, new_state}
end
end
演示:
代码中有几个问题:
子项
需要是一个列表GenServer.start\u link
的第二个参数应该是interval
,而不是[interval]
inspect()
状态:计时器。发送间隔/1
,只有/2
和/3
@@ -8,7 +8,7 @@ defmodule SubscriptionManagerSupervisor do
# supervisor callback
def init([]) do
interval = 1000
- children = worker(SubscriptionManagerServer, [interval])
+ children = [worker(SubscriptionManagerServer, [interval])]
supervise(children, strategy: :one_for_one)
end
end
@@ -18,20 +18,20 @@ defmodule SubscriptionManagerServer do
import Logger
def start_link(interval) do
- GenServer.start_link(__MODULE__, [interval])
+ GenServer.start_link(__MODULE__, interval)
end
def init(interval) do
state = :calendar.universal_time()
- Logger.info "SubscriptionManagerServer init(). State: #{state} interval: #{interval}"
+ Logger.info "SubscriptionManagerServer init(). State: #{inspect(state)} interval: #{interval}"
# This will send message to self on the interval. handle_info handles it.
- :timer.send_interval(interval)
+ :timer.send_interval(interval, :tick)
{:ok, state}
end
def handle_info(url, state) do
new_state = :calendar.universal_time()
- Logger.info "SubscriptionManager handle_info(). new_state: #{new_state}"
+ Logger.info "SubscriptionManager handle_info(). new_state: #{inspect(new_state)}"
{:noreply, new_state}
end
end
演示:
你的
GenServer.start\u link
使用interval
而不是[interval]
。试着替换你的GenServer.start\u link
使用interval
而不是[interval]
。试着替换它根据主管,我觉得我什么都试过了。然而,我没有意识到孩子必须是一个列表。这是关键。谢谢关于主管,我觉得我什么都试过了。然而,我没有意识到孩子必须是一个列表。这是关键。谢谢