jhefreyzz
Try learning again Phoenix channels and stumbled upon a dialyzer warning I can’t seem to solve.
My whole channel code below.
@impl true
def join("room:lobby", payload, socket) do
send(self(), :after_join)
{:ok, assign(socket, current_user: payload)}
end
@impl true
def handle_info(:after_join, socket) do
{:ok, _} =
Presence.track(socket, socket.assigns.current_user.id, %{
nickname: socket.assigns.current_user.nickname,
online_at: inspect(System.system_time(:second))
})
messages = MessageView.render("messages.json", %{messages: Chat.list_messages()})
push(socket, "presence_state", Presence.list(socket))
push(socket, "list_messages", messages)
{:noreply, socket}
end
@impl true
def handle_in("create_message", payload, socket) do
{:ok, user} = Accounts.get_user!(socket.current_user.id)
{:ok, message} = Chat.create_message(user, payload)
message = MessageView.render("message.json", %{message: message})
broadcast(socket, "message_created", message)
{:noreply, socket}
end
Dialyzer warnings:
The inferred type for the 3rd argument is not a
supertype of the expected type for the handle_in/3 callback
in the Phoenix.Channel behaviour.
Success type:
%Phoenix.Socket{:current_user => atom() | %{:id => _, _ => _}, :joined => true, _ => _}
Behaviour callback type:
%Phoenix.Socket{
:assigns => map(),
:channel => atom(),
:channel_pid => pid(),
:endpoint => atom(),
:handler => atom(),
:id => nil | binary(),
:join_ref => _,
:joined => boolean(),
:private => %{},
:pubsub_server => atom(),
:ref => _,
:serializer => atom(),
:topic => binary(),
:transport => atom(),
:transport_pid => pid()
}
Type mismatch for @callback handle_in/3 in Phoenix.Channel behaviour.
Expected type:
{:noreply,
%Phoenix.Socket{
:assigns => map(),
:channel => atom(),
:channel_pid => pid(),
:endpoint => atom(),
:handler => atom(),
:id => nil | binary(),
:join_ref => _,
:joined => boolean(),
:private => %{},
:pubsub_server => atom(),
:ref => _,
:serializer => atom(),
:topic => binary(),
:transport => atom(),
:transport_pid => pid()
}}
| {:noreply,
%Phoenix.Socket{
:assigns => map(),
:channel => atom(),
:channel_pid => pid(),
:endpoint => atom(),
:handler => atom(),
:id => nil | binary(),
:join_ref => _,
:joined => boolean(),
:private => %{},
:pubsub_server => atom(),
:ref => _,
:serializer => atom(),
:topic => binary(),
:transport => atom(),
:transport_pid => pid()
}, :hibernate | timeout()}
| {:reply, atom() | {atom(), map()},
%Phoenix.Socket{
:assigns => map(),
:channel => atom(),
:channel_pid => pid(),
:endpoint => atom(),
:handler => atom(),
:id => nil | binary(),
:join_ref => _,
:joined => boolean(),
:private => %{},
:pubsub_server => atom(),
:ref => _,
:serializer => atom(),
:topic => binary(),
:transport => atom(),
:transport_pid => pid()
}}
| {:stop, _,
%Phoenix.Socket{
:assigns => map(),
:channel => atom(),
:channel_pid => pid(),
:endpoint => atom(),
:handler => atom(),
:id => nil | binary(),
:join_ref => _,
:joined => boolean(),
:private => %{},
:pubsub_server => atom(),
:ref => _,
:serializer => atom(),
:topic => binary(),
:transport => atom(),
:transport_pid => pid()
}}
| {:stop, _, atom() | {atom(), map()},
%Phoenix.Socket{
:assigns => map(),
:channel => atom(),
:channel_pid => pid(),
:endpoint => atom(),
:handler => atom(),
:id => nil | binary(),
:join_ref => _,
:joined => boolean(),
:private => %{},
:pubsub_server => atom(),
:ref => _,
:serializer => atom(),
:topic => binary(),
:transport => atom(),
:transport_pid => pid()
}}
Actual type:
{:noreply,
%Phoenix.Socket{:current_user => atom() | %{:id => _, _ => _}, :joined => true, _ => _}}
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Sebb
according to your usage dialyzer thinks that socket has a
current_userfield.current_useris insocket.assigns.jhefreyzz
Yeah, I already fixed it a while a go but forgot to update the thread.