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Send MQTT from Browser with simple nodejs [duplicate]

I have a virtual machine that is supposed to be the host, which can receive and send data. The first picture is the error that I'm getting on my main machine (from which I'm trying to send data from). The second picture is the mosquitto log on my virtual machine. Also I'm using the default config, which as far as I know can't cause these problems, at least from what I have seen from other examples. I have very little understanding on how all of this works, so any help is appreciated.
What I have tried on the host machine:
Disabling Windows defender
Adding firewall rules for "mosquitto.exe"
Installing mosquitto on a linux machine

Starting with the release of Mosquitto version 2.0.0 (you are running v2.0.2) the default config will only bind to localhost as a move to a more secure default posture.
If you want to be able to access the broker from other machines you will need to explicitly edit the config files to either add a new listener that binds to the external IP address (or 0.0.0.0) or add a bind entry for the default listener.
By default it will also only allow anonymous connections (without username/password) from localhost, to allow anonymous from remote add:
allow_anonymous true
More details can be found in the 2.0 release notes here

You have to run with
mosquitto -c mosquitto.conf
mosquitto.conf, which exists in the folder same with execution file exists (C:\Program Files\mosquitto etc.), have to include following line.
listener 1883 ip_address_of_the_machine(192.168.1.1 etc.)

By default, the Mosquitto broker will only accept connections from clients on the local machine (the server hosting the broker).
Therefore, a custom configuration needs to be used with your instance of Mosquitto in order to accept connections from remote clients.
On your Windows machine, run a text editor as administrator and paste the following text:
listener 1883
allow_anonymous true
This creates a listener on port 1883 and allows anonymous connections. By default the number of connections is infinite. Save the file to "C:\Program Files\Mosquitto" using a file name with the ".conf" extension such as "your_conf_file.conf".
Open a terminal window and navigate to the mosquitto directory. Run the following command:
mosquitto -v -c your_conf_file.conf
where
-c : specify the broker config file.
-v : verbose mode - enable all logging types. This overrides
any logging options given in the config file.

I found I had to add, not only bind_address ip_address but also had to set allow_anonymous true before devices could connect successfully to MQTT. Of course I understand that a better option would be to set user and password on each device. But that's a next step after everything actually works in the minimum configuration.

For those who use mosquitto with homebrew on Mac.
Adding these two lines to /opt/homebrew/Cellar/mosquitto/2.0.15/etc/mosquitto/mosquitto.conf fixed my issue.
allow_anonymous true
listener 1883

you can run it with the included 'no-auth' config file like so:
mosquitto -c /mosquitto-no-auth.conf
I had the same problem while running it inside docker container (generated with docker-compose).
In docker-compose.yml file this is done with:
command: mosquitto -c /mosquitto-no-auth.conf

CORS policy error on file in same folder as HTML [duplicate]

I am getting the following error:
XMLHttpRequest cannot load file:///C:/Users/richa.agiwal/Desktop/get/rm_Library/templates/template_viewSettings.html. Cross origin requests are only supported for HTTP.
I realize that this question has been answered before, but I still have not found a solution to my problem. I tried running chrome.exe --allow-file-access-from-files from the command prompt, and moved the file to the local file system, but I still get the same error.
I appreciate any suggestions!

If you are doing something like writing HTML and Javascript in a code editor on your personal computer, and testing the output in your browser, you will probably get error messages about Cross Origin Requests. Your browser will render HTML and run Javascript, jQuery, angularJs in your browser without needing a server set up. But many web browsers are programed to watch for cross site attacks, and will block requests. You don't want just anyone being able to read your hard drive from your web browser. You can create a fully functioning web page using Notepad++ that will run Javascript, and frameworks like jQuery and angularJs; and test everything just by using the Notepad++ menu item, RUN, LAUNCH IN FIREFOX. That's a nice, easy way to start creating a web page, but when you start creating anything more than layout, css and simple page navigation, you need a local server set up on your machine.
Here are some options that I use.
Test your web page locally on Firefox, then deploy to your host.
or: Run a local server
Test on Firefox, Deploy to Host
Firefox currently allows Cross Origin Requests from files served from your hard drive
Your web hosting site will allow requests to files in folders as configured by the manifest file
Run a Local Server
Run a server on your computer, like Apache or Python
Python isn't a server, but it will run a simple server
Run a Local Server with Python
Get your IP address:
On Windows: Open up the 'Command Prompt'. All Programs, Accessories, Command Prompt
I always run the Command Prompt as Administrator. Right click the Command Prompt menu item and look for Run As Administrator
Type the command: ipconfig and hit Enter.
Look for: IPv4 Address . . . . . . . . 12.123.123.00
There are websites that will also display your IP address
If you don't have Python, download and install it.
Using the 'Command Prompt' you must go to the folder where the files are that you want to serve as a webpage.
If you need to get back to the C:\ Root directory - type cd/
type cd Drive:\Folder\Folder\etc to get to the folder where your .Html file is (or php, etc)
Check the path. type: path at the command prompt. You must see the path to the folder where python is located. For example, if python is in C:\Python27, then you must see that address in the paths that are listed.
If the path to the Python directory is not in the path, you must set the path. type: help path and hit Enter. You will see help for path.
Type something like: path c:\python27 %path%
%path% keeps all your current paths. You don't want to wipe out all your current paths, just add a new path.
Create the new path FROM the folder where you want to serve the files.
Start the Python Server: Type: python -m SimpleHTTPServer port Where 'port' is the number of the port you want, for example python -m SimpleHTTPServer 1337
If you leave the port empty, it defaults to port 8000
If the Python server starts successfully, you will see a msg.
Run You Web Application Locally
Open a browser
In the address line type: http://your IP address:port
http://xxx.xxx.x.x:1337 or http://xx.xxx.xxx.xx:8000 for the default
If the server is working, you will see a list of your files in the browser
Click the file you want to serve, and it should display.
More advanced solutions
Install a code editor, web server, and other services that are integrated.
You can install Apache, PHP, Python, SQL, Debuggers etc. all separately on your machine, and then spend lots of time trying to figure out how to make them all work together, or look for a solution that combines all those things.
I like using XAMPP with NetBeans IDE. You can also install WAMP which provides a User Interface for managing and integrating Apache and other services.

Simple Solution
If you are working with pure html/js/css files.
Install this small server(link) app in chrome. Open the app and point the file location to your project directory.
Goto the url shown in the app.
Edit: Smarter solution using Gulp
Step 1: To install Gulp. Run following command in your terminal.
npm install gulp-cli -g
npm install gulp -D
Step 2: Inside your project directory create a file named gulpfile.js. Copy the following content inside it.
var gulp = require('gulp');
var bs = require('browser-sync').create();
gulp.task('serve', [], () => {
bs.init({
server: {
baseDir: "./",
},
port: 5000,
reloadOnRestart: true,
browser: "google chrome"
});
gulp.watch('./**/*', ['', bs.reload]);
});
Step 3: Install browser sync gulp plugin. Inside the same directory where gulpfile.js is present, run the following command
npm install browser-sync gulp --save-dev
Step 4: Start the server. Inside the same directory where gulpfile.js is present, run the following command
gulp serve

To add to Alan Wells's elaborate answer here is a quick fix
Run a Local Server
you can serve any folder in your computer with Serve
First, navigate using the command line into the folder you'd like to serve.
Then
npx i -g serve
serve
or if you'd like to test Serve without downloading it
npx serve
and that's it! You can view your files at http://localhost:5000

If you are using vscode, you can easily start a liver server. Click liver server at the bottom of the page, once the server is started, vscode will tell the port the project is running. Do ensure your project folder is the workspace

This error is happening because you are just opening html documents directly from the browser. To fix this you will need to serve your code from a webserver and access it on localhost. If you have Apache setup, use it to serve your files. Some IDE's have built in web servers, like JetBrains IDE's, Eclipse...
If you have Node.Js setup then you can use http-server. Just run npm install http-server -g and you will be able to use it in terminal like http-server C:\location\to\app.
Kirill Fuchs

If you use the WebStorm Javascript IDE, you can just open your project from WebStorm in your browser. WebStorm will automatically start a server and you won't get any of these errors anymore, because you are now accessing the files with the allowed/supported protocols (HTTP).

I was facing this error while I deployed my Web API project locally and I was calling API project only with this URL given below:
localhost//myAPIProject
Since the error message says it is not http:// then I changed the URL and put a prefix http as given below and the error was gone.
http://localhost//myAPIProject

Depends on your needs, but there is also a quick way to temporarily check your (dummy) JSON by saving your JSON on http://myjson.com. Copy the api link and paste that into your javascript code. Viola! When you want to deploy the codes, you must not forget to change that url in your codes!

Is it possible to expose nodes localhost to my host?

I am currently working on an Ionic based project. due to the fact I don't want to install node.js locally I tried DDEV, even it is supposed to be a PHP development environment.
However, when serving my application via ionic serve -l the frontend of my app is built and should be accessible (within the container) on http://localhost:8200. Well, I have to expose this port to my host I guess.
To do so I already tried a few configurations, but nothing worked out. For example:
I configured the nginx-site-conf for listening on port 8200. A weak try, I know but I had to try.
Furthermore I created a docker-compose.override.yaml and added the port 8200 to be exposed to my host. Didn't work out well.
Has anyone an idea or is DDEV just not the right tool for that job?

You'll want to do a docker-compose.extraport.yaml (name of the file is arbitrary) that exposes that port to the host.
I tried this .ddev/docker-compose.extraport.yaml and it worked fine. I just tested it with nc -l -p 8200 inside the container, and telnet localhost 8200 on the host.
version: '3.6'
services:
web:
ports:
- published: 8200
target: 8200
Details about adding extra docker-compose files are at https://ddev.readthedocs.io/en/latest/users/extend/additional-services/ and https://ddev.readthedocs.io/en/latest/users/extend/custom-compose-files/ - those are mostly aimed at people creating a completely new service, but it all works the same for overriding as here.

Meteor js - unable to insert data on Mongo through console

I'm following an udemy course on Meteor.
Steps to replicate my problem:
1) On CMD:
meteor create Leaderboard
cd Leaderboard
meteor npm install
meteor run
(server starts, localhost:3000)
2) Then, I deleted the contents of main.css, main.html & main.js (under client folder).
3) Opened main.js and added the following line:
PlayersList = new Mongo.Collection('players');
On Chrome's console I typed 'PlayersList' and got the following:
M…o.Collection {_transform: null, _connection: Connection, _collection: LocalCollection, _name: "players", _driver: LocalCollectionDriver…}
THE PROBLEM
When I type this on console:
PlayersList.insert({ name: 'David', score: 0 });
This is the Error:
"eebRFhA9vbSfHzPKk"
meteor.js?hash=e3f53db…:930 insert failed: Method '/players/insert' not found
Why am I getting it? I followed the exact steps provided by the instructor. What's wrong here?

That error is caused by the collection not having been defined on the server, only on the client.
The default app created by meteor create app contains two main.js files, one in the client and one in server folder. These specially-named folders work exactly as you'd expect - the content in them is only loaded on the client or server. Apparently you added the collection definition only to the one in client. To fix this, if you put a file outside these specially-named folders - say create a folder named collections, and add a PlayersList.js file there and define your collection there, then it will be loaded by both and work.
Alternatively (this is the recommended method when developing a larger app) if you put the file that defines the collection into a folder named imports then you can import that to your server and client code separately, instead of Meteor auto-including it. You can read more about Meteor application structure here.

Try this :-
PlayersList._collection.insert({ name: 'David', score: 0 });

cannot start nodejs web api hosted in Azure

Learning nodejs and started to created my own restful API using restify.
I have created a very simple server.js file which contains basically a hello world type example starting up like:
server.post('/api/messages', servicemanager.verifyFramework(), servicemanager.listen());
server.get(/.*/, restify.serveStatic({
'directory': '.',
'default': 'index.html'
}));
server.listen(process.env.port || 3978, function () {
console.log('%s listening to %s', server.name, server.url);
});
which works fine locally. I cant hit http://localhost:3978 and I can test my API calls just fine calling http://localhost:3978/api/messages.
I have deployed my code into bitbucket and now I want to host these APIs in Azure using App Services.
My project structure is like so:
/topfolder
-/myproject
-/node_modules
-/node_modules...
server.js
package.json
index.html
When I setup the new app service in Azure, I can see that the deployment receives the code from BB, but the service never responds to my requests.
I have setup the home path of the app to live in: /site/wwwroot/topfolder/myproject and I can see the index.html when I navigate to http://myproject.azurewebsites.net so thats good.
I actually get a 404 error:
The resource you are looking for has been removed, had its name changed, or is temporarily unavailable.
There are heaps of examples of how to setup continuous deployment using bitbucket and for the most part, they all seem to work, but my server.js file doesnt seem to be the getting called or starting up.
How can I debug whats going on here?
Is the packages.json file used in this scenario by Azure?
Thanks.

As the root directory path of the application hosted on Azure App Services, is D:\home\site\wwwroot. And about the nodejs application, the Azure fabric will find the entrance script in root directory like server.js. And the requests are handled via web.config in root directory. If there is missing server.js or web,config file, you will occur 404 error.
You can try to modify or your application's structure, like to:
-/node_modules
-/node_modules...
server.js
package.json
index.html
Then, you deploy your application to Azure via GIT or from BB, the Azure deployment task will run command npm install and generate the web.config wile in the root directory.
Any further concern, please feel free to let me know.