Python in to the magic mirror.

[paulvanderheijden90]

@sean said in Python in to the magic mirror.:

@paulvanderheijden90
Your node_helper.js is not correct.

Hello Sean,
Why is it wrong? I copy it from your post earlier.
I started in Dev mode. I noticed that wenn I add the Node_helper.js module in the MMM-P2000 map the Magic mirror crashes and give only black screen.
I studyed the Node_helper file. I see in the first line you define the function and in the second line you define the settings for that function. So that’s clear to me. In the next lines you define the stdout of the process and copy it in de Console Log. so that’s also clear for me. So I down’t know why is it not working and crashes.

I made in the same map ( home/pi/src/ ) a file called test.py Here I defined a string and I write the string to the stdout so as you say before the python project don’t need a separate call. So that should work as well.

Node_helper.js:

Python project:

I also getting in to the module setup so I changed the MMM-P2000.js and I think it is oke like this.
First the start function restart every 1000mS the dom function.
then the getdom Function is now showing the test “Hello World” in the module
so that should be oke aswell. I

How do I need to link the socked notification message to the Module string?

[sdetweil]

@paulvanderheijden90 node helper needs to look like this
see the doc here https://github.com/MichMich/MagicMirror/tree/master/modules#the-node-helper-node_helperjs

const NodeHelper = require('node_helper');

// any other imports (javascript require)

module.exports = NodeHelper.create({
   // local variables 
    self: 0,
		pins_loaded:[],
		pin_index:0,
		results:{},
		using_chartjs: true,
		suspended: false,
		timer:null,

    start: function() {
        console.log("Starting module: " + this.name);
        self = this;
    },
 socketNotificationReceived: function(notification, payload) {
        // usually the module send the config data down to the node_helper
        if (notification === 'CONFIG') {
            this.config = payload;
        }

// any other functions, u need, note, after each function is a ',' (comma)
}
});

[A Former User]

node_helper.js is helper script of your module to use various features of NodeJS. your main module script(MMM-P2000.js) is just front-end javascript on Browser(Electron/Chromium). So when you need more features which are not supported on browser level, use node_helper.js

MMM-P2000.js and node_helper.js can communicate with each other by socketNotification.

you need to make proper node_helper.js which could be used in MM framework.

Usual format is

var NodeHelper = require("node_helper")

module.exports = NodeHelper.create({
  start: function() {
    // ...
  },
  socketNotificationReceived: function(notification, payload) {
    // ...
  },
})

There are two entry points in node_helper.js from your main module .

start will be called when MM is executed and your module is loaded. Usually you can prepare things here.

socektNotificationReceived will be called when your main module send socketNotification with sendSocketNotification.

With this, you can transfer config values, specific datas or order to do something.

Your current MMM-P2000.js is not so good to use. I recommend you continue to read my https://forum.magicmirror.builders/topic/8534/head-first-developing-mm-module-for-extreme-beginners more.

[paulvanderheijden90]

I changed the Node_helper.js:

But the minute I run the Start dev I get white screens. so im not able to debug anything.
Can I get a hand ?

[sdetweil]

the spawn stuff needs to be INSIDE the node helper…

probably called in Start or in the socketNotificationReceived, when the config is sent down from the module…

[paulvanderheijden90]

@sdetweil Thank you for you’re information.
I changed it like you said but unfortunly still get the With screens.

[A Former User]

@paulvanderheijden90
If possible, Instead image, post code itself.
Anyway, You’d better to read docs more carefully.

MMM-P2000.js

/// MMM-P2000.js

Module.register("MMM-P2000", {
  getDom: function() {
    var e = document.createElement("div")
    e.id = "DISPLAY"
    return e
  },
  notificationReceived: function(notification, payload, sender) {
    switch(notification) {
      case "DOM_OBJECTS_CREATED":
        var timer = setInterval(()=>{
          this.sendSocketNotification("GIVE_ME_DATA")
        }, 1000)
        break
    }
  },
  socketNotificationReceived: function(notification, payload) {
    switch(notification) {
      case "HERE_IS_DATA":
        var e = document.getElementById("DISPLAY")
        e.innerHTML = payload
        break
    }
  },
})

node_helper.js

/// node_helper.js
const spawn = require("child_process").spawn
var NodeHelper = require("node_helper")

module.exports = NodeHelper.create({
  socketNotificationReceived: function(notification, payload) {
    switch(notification) {
      case "GIVE_ME_DATA":
        this.job()
        break
    }
  },
  job: function() {
    var process = spawn("python", ["/home/pi/src/test.py"])
    process.stdout.on("data", (data)=>{
      console.log(data)
      this.sendSocketNotification("HERE_IS_DATA", data)
    })
  }
})

I didn’t test. I wrote this code with only my brain. so there could be errors, but you can catch the concept.

[paulvanderheijden90]

@Sean Thank you very much im going to check the code and see if I can implement it in the magic mirror.
Thank you I will let you know

[paulvanderheijden90]

@sean
Hello Sean, Again thank you very much for you’re valued help!.

I spend yesterday after midday and evening with a friend figure out how you’re code is working. and we did some tests to send also somthing back to the Node helper and alote came clear by you’re example.
So realy thank u very much.

To day I spend my morning figure out one last problem the text on the screen is [ Object ArrayBuffer] and not the string I put true the stdout.write.
The text that is displayed on the screen is :

I did some debugging of my own. and wenn I override the data in the node helper just after it come from the spawn function this is displayed on the mirror. so the code is working until the spawn function.

/// node_helper.js

const spawn = require("child_process").spawn

var NodeHelper = require("node_helper")



module.exports = NodeHelper.create({

  socketNotificationReceived: function(notification, payload) {

    switch(notification) {

      case "GIVE_ME_DATA":

        this.job()

        break

    }

  },

  job: function() {

    var process = spawn("python", ["/home/pi/src/test.py"])

    process.stdout.on("data", (data)=>{
	data= "test hello World"
      console.log(data)

      this.sendSocketNotification("HERE_IS_DATA", data)

    })

  }

})

So i tested also the python test project. and wenn I run it in the terminal it give no error. so the python project is fine aswell I think.

import sys


sys.stdout.write("Hallo Ik ben Paul")

So I think the spawn function is not correct at this time?
Can you help me out one more time please?

[A Former User]

@paulvanderheijden90 said in Python in to the magic mirror.:

Object ArrayBuffer

is one of javascript Object type. not text itself. (Sorry for my prior example. it needs to be converted from Object to HTMLText.)

https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/ArrayBuffer

process.stdout.on("data", (data)=>{
  console.log(data) 
  // You can see the structure of this `data` object(ArrayBuffer) on the shell terminal.

  var result = String.fromCharCode.apply(null, new Uint16Array((data))
  // You need to convert or filter or manipulate `data` object whatever for your real usage.

  this.sendSocketNotification("HERE_IS_DATA", result)
 })