凤凰频道从项目外的客户端发送消息

Question

我想向我的 Phoenix 应用程序的用户频道发送消息。我在 user_channel.ex 中加入了一个 user_token，频道为 users:user_token。我通过调用广播方法从另一个名为 toy_controller 的控制器成功地做到了这一点。广播方式在用户频道。我写了一个 jQuery 文件来处理事件。我一直在寻找可以从项目外部向同一频道发送消息的东西，因为我想做一些物联网的事情。我已经尝试了一个名为 occamy.socket 的 python 模块和它在内部使用的 Phoenix 的 JS 客户端。然后，我总是发现断开连接。我无法弄清楚 Phoenix 的 websocket 连接的确切地址。如果我在该项目文件夹本身中使用 Phoenix npm 库进行尝试，它总是显示 ReferenceError: window is not defined。而且，我认为这是因为 web/static/js/socket.js 文件中套接字的初始化部分被写为

let socket = new Socket("/socket", {params: {token: window.userToken}})

，但我不确定。我试过的东西在

下面

var Socket = require("phoenix-socket").Socket;
var socket = new Socket("ws://localhost:4000/socket");

在python客户端中，我也试图连接到这个地址，但出现断开连接错误。我想出于物联网目的这样做，我想在其中监视用户的传感器数据。每个用户都将拥有自己的传感器进行监控。因此，我已将频道 topic:subtopic 频道配置为 users:user_token 。我需要使用用户的那些唯一令牌将消息从我的 raspberry pi 发送到该频道。我的 user_channel、user.js、app.js 和 socket.js 如下所示。

//web/static/js/socket.js
import {Socket} from "phoenix"

let socket = new Socket("/socket", {params: {token: window.userToken}})


socket.connect()


export default socket

//web/static/app.js


import "phoenix_html"
import user from "./user"

#web/channels/user_channel.ex
defmodule Tworit.UserChannel do
    use Tworit.Web, :channel

    def join("users:" <> user_token, payload, socket) do
        if authorized?(payload) do
          {:ok, "Joined To User:#{user_token}", socket}
      else
          {:error, %{reason: "unauthorized"}}
      end
    end


    def handle_in("ping", payload, socket) do
        {:reply, {:ok, payload}, socket}
    end


    def handle_in("shout", payload, socket) do
       broadcast socket, "shout", payload
       {:noreply, socket}
    end


    def handle_out(event, payload, socket) do
        push socket, event, payload
        {:noreply, socket}
    end


     defp authorized?(_payload) do
       true
     end

    def broadcast_change(toy, current_user) do
       payload = %{
        "name" => toy.name,
        "body" => toy.body
       }
      Tworit.Endpoint.broadcast("users:#{current_user.token}", "change", payload)
    end

end

//web/static/js/user.js
import socket from "./socket"

$(function() {
  let ul = $("ul#em")

  if (ul.length) {
    var token = ul.data("id")
    var topic = "users:" + token
  
    // Join the topic
    let channel = socket.channel(topic, {})
    channel.join()
      .receive("ok", data => {
        console.log("Joined topic", topic)
      })
      .receive("error", resp => {
        console.log("Unable to join topic", topic)
      })
    channel.on("change", toy => {
     console.log("Change:", toy);
     $("#message").append(toy["name"])
    })
  }
});

Answer 1

最后，我能够从 python 程序异步发送和接收消息。它使用来自 python 的 websockets asyncio 模块。我想出了凤凰频道所需的各种事件，比如 'phx_join' 加入一个主题等等。因此，以下程序有效。

import asyncio
import websockets
import json
import time
from random import randint
import serial

from pyfirmata import Arduino, util

board = Arduino('/dev/ttyACM1')

it = util.Iterator(board)
it.start()
board.analog[0].enable_reporting()
board.analog[1].enable_reporting()
board.analog[2].enable_reporting()
board.analog[3].enable_reporting()

import RPi.GPIO as gpio

gpio.setmode(gpio.BCM)
gpio.setup(14, gpio.OUT)


async def main():
    async with websockets.connect('ws://IP_addr:4000/socket/websocket') as websocket:
        data = dict(topic="users:user_token", event="phx_join", payload={}, ref=None)
        #this method joins the phoenix channel
        await websocket.send(json.dumps(data))

        print("Joined")

        while True:
            msg = await retrieve() # waits for data from arduino analog pins
            await websocket.send(json.dumps(msg)) # sends the sensor output to phoenix channel

            print("sent")
            call = await websocket.recv() # waits for anything from the phoenix server
            control = json.loads(call)

            # I have sent values from 2 buttons for swicthing a led with event 'control'

            if(control['event'] == "control"):
                event(control['payload']['val']) #swiches the led as per the input from event 'control'


            print("< {}".format(call))

def event(val):
    if(val == "on"):
        gpio.output(14, True)
    if(val == "off"):
        gpio.output(14, False)

async def retrieve():
    #analog read
    load = board.analog[0].read()
    pf = board.analog[1].read()
    reading = board.analog[2].read()
    thd = board.analog[3].read()
    output = {"load": load, "pf": pf, "reading": reading,"thd": thd}

    msg = dict(topic="users:user_token", event="sensor_output", payload=output, ref=None) # with 
    #event "sensor_outputs" 
    #the phoenix server displays the data on to a page.

    print(msg)
    return(msg)

asyncio.get_event_loop().run_until_complete(main())
asyncio.get_event_loop().run_forever()

凤凰频道从项目外的客户端发送消息

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