setting up node-supervisor for nodeJS - node.js

Hi I'm a nodeJS and command line noob. I've managed to get a linux box up running and everything is fine. However restarting the node scripts every time I make changes is beginning to frustrate.
So I'm trying to set up node supervisor.
https://github.com/isaacs/node-supervisor
All installed fine but
when I try to set it up using the following from the command line (putty)
supervisor test.js
I get
supervisor: command not found
Does anyone have any idea why this would be?
many thanks

it means supervisor isn't in your path or wasn't set with execute permissions. Find supervisor then use the full path to it. it's possibly still in the build folder if you forgot to install it system-wide.

You should install supervisor globally with -g command option
> npm install -g supervisor

Related

How to run asp.net core application using pm2 on linux server

I have updated my asp.net core API over linux server using kestrel, I want to run the core application using pm2. Let me know if any buddy has already done this kind of task.
What I have tried is:
I Installed the pm2 on my linux server (not globally). It installed successfully but when I'm trying to run the code using pm2, I am getting error pm2, command not found
I tried to install the pm2 globally but getting write access issue in node modules some where but I can't give global write access.
Thanks in advance for your help :)
pm2, command not found means the binary is not found cause it is most probably missing in your PATH variable. The path differs whether you install it globally or not - see pm2-command-not-found how to figure out the path and how to add it to your PATH variable.
When not installed globally, the binaries are under ~\node_modules. This you have to add the actual binary path e.g. ~/node_modules/pm2/bin to the PATH variable or you call it directly using ~/node_modules/pm2/bin/pm2
For the installation problem mentioned above, run the installation as sudo npm install -g pm2

Running electron as root on Linux

I am making an application with electron which uses the wiring-pi library. This needs access to the GPIO on my Raspberry Pi, which requires root.
When I run electron . in the folder, the app opens fine but then says (in the terminal):
wiringPiSetup: Must be root. (Did you forget sudo?)
However when I try sudo electron ., I get an error:
sudo: electron: command not found
Does anyone know why this is happening?
Also, for the record, the same thing happens when I run npm as root:
pi#raspberrypi:~/rubiks-robot $ sudo npm
sudo: npm: command not found
Any ideas of how I can fix this issue and run Electron as root?
it looks like a problem of environment variables. The environmnet variables are set for your user but not for root.
Try to ship your variables with the "-E" switch of the sudo command:
sudo -E command
Please try to see here for other similar questions
How to keep Environment Variables when Using SUDO

npm.cmd closes instantly after few seconds

I'm learning nodeJs. I managed to run nodejs commands on cmd and it works fine. Now I want to install express framework and for that in the tutorial I'm following it asks to type sudo install -g express on npm command prompt. So I typed npm in my windows search, and clicked on it. Right after few seconds less than 3 it closes straight away.
I found that npm.cmd exist in nodejs directory where node.exe found. What could be the problem here. If I were to type the above mentioned command in windows cmd, it says sudo is unrecognized program.SO must I use npm cmd?
After running cmd.exe , I guess you would have node installed but still run node -v , it should respond with the version meaning it's working.
Now if you want to explicitly install express.js you just have to run on, the command prompt itself,
npm install express -g.
Anyways you can follow this link from their official website. Hope it helps. Also sudo is a program for Unix like operating systems, just in case you needed it.

How can I get the slc command to work on Ubuntu?

I have installed Strongloop using npm install -g strongloop on my Ubuntu 14.04 server. The slc command does not work. It says
The program 'slc' is currently not installed. You can install it by typing:
sudo apt-get install heimdal-multidev
How can I get it to run the Strongloop CLI instead of looking for this package? I have added this to my PATH and it still doesn't work. Any ideas?
Other Strongloop commands, like sl-build work and strongloop is listed in npm list -g.
Ubuntu 14 with node.js 4.1.2
By default somehow slc is not created or not added to PATH.
I solved this problem by adding symlink:
sudo ln -s /usr/lib/node_modules/strongloop/bin/slc.js /usr/bin/slc
A soft link named slc should have been created at /usr/local/bin which will point to strongloop binary.
Please verify if the following exists.
/usr/local/lib/node_modules/strongloop/bin/slc
If no, then strongloop did not get installed successfully, otherwise verify the existence of the softlink slc at /usr/local/bin/.
/usr/local/bin/slc -> /usr/local/lib/node_modules/strongloop/bin/slc
If yes, then /usr/local/bin needs to be added to the $PATH, otherwise create the softlink and verify that /usr/local/binin $PATH.
Looks like the Node installation that optionally comes with a Digital Ocean Droplet installs to a different location that's not in $PATH. I'm pretty sure that was the issue. Anyways, I fixed it by spinning up a server without Node pre-installed and followed this guide. Just use npm install -g strongloop instead of strong-cli because the latter has been deprecated.
Ubuntu 14.04 with node.js 4.4.2 (LTS) :
The installation of strongloop was done without any errors but slc was not added to the PATH. I solved this problem by adding the symlink:
sudo ln -s /usr/local/lib/node_modules/strongloop/bin/slc.js /usr/bin/slc
Actually i am not sure my case matches with yours but i want to share my experience. i got the same message anyway.
I realized that i had changed prefix of global packets before. Then i checked prefix with the following command.
$ npm config get prefix
/home/myUser/.node_modules_global
Then i added the path to PATH variable (but .profile, .bash_profile files will be better) in active command line window and problem solved.

'Express' is not recognized command (windows)

Okay I am running node on windows (7). Using npm I just installed modules to d:\ directory. Therefore my files structure looks like the following:
D:\
-myproject
-node_modules
-.bin
-express
However, when I am in this 'myproject' directory, I can't seem to run 'express' for example:
D:\myproject\express site
'express' is not recognized as an internal or external command, operable program or batch file.
Am I doing anything wrong?
Try:
npm install -g express-generator#3
That solved problem for me.
Edit: for version 4
npm install express-generator -g
Description:
express is the package for dependency of express js.
express-generator is the package for enabeling express command and create a sample project, etc.
Assuming that this is kept separate for the decoupling of project dependency with cli tool of express.
Another SO ref: https://stackoverflow.com/a/41311733/1666582
Here's what to type in the command line to make it work in windows:
npm install express-generator -g
[Source: http://expressjs.com/starter/generator.html]
My guess is that you didn't install Express globally. You can install express globally (and therefore available in your PATH) with the following command (see http://expressjs.com/guide.html) :
npm install -g express
The way you install it is available only in the folder that you installed it and there is nothing wrong with that approach. There is very little advantage of having it available globally.
If express is not in your PATH you can run it by entering the full path to it:
\myproject\node_modules\.bin\express.cmd
With the release of Express 4.0.0 it looks like you need to do
npm install -g express-generator
We need to set path for express global directory
C:\Users[User_Name]\AppData\Roaming\npm\
After add a new path, please reopen the CMD console
Tried all of these and never worked. A repair of Node.js by kicking of installation and selecting repair option does the magic.
Cheers
What worked for me was:
I used the windows command prompt instead of the node.js command prompt.
In windows 10 simply type in the windows search bar for "node"
You see a node.js desktop app and a node js command prompt.
Choose the "node js command prompt"
Type in the command prompt
npm install express-generator -g
Then navigate somewhere and type in:
express your-website-text-here -e
A directory with express files will be generated. Also now you won't see the express error.
I was able to fix with the following package install:
npm install express-generator -g
Thanks
When you install Node.js, the below path is added to the Windows OS %Path% variable, I'm presuming similar happens on other operating systems as well:
C:\Users\<your-windows-username>\AppData\Roaming\npm
In my case, because I use a work Windows laptop for an employer that severely restricts what employees can do on their machines (I.e. many actions require elevated admin privileges), Node.js was being prevented from adding the above path to the Windows %Path% environment variable, and much to my chagrin the Node.js installation was silent about it. Navigate to above folder and you will notice the express command lives there, see screenshot below.
How did I figure this out? I did a fresh installation of Node.js on a personal, home Windows machine that has no admin privilege restrictions like my work machine does, compared the before and after %Path% value, and noticed the addition of that path. My work machine was missing it.
I had no choice but to add the path manually to %Path%, and then express was recognized from within any path I ran it.
I was able to fix this with:
npm install express-generator -g
I tried all the above solution, no luck for me.
Open "Node.js" command prompt and tried as administrator. It is working fine for me. Don't try with windows command prompt.
I have the same problem and understand the solution, but i can´t undestand why, running npm install -g express, express.bat isn´t added automatically to Path.
Running with npm install -g express have the same result. Download packages and store in node_modules, but express.bat isn´t added to path.
Run the node command prompt as administrator and then install express globaly
npm install -g express
and then go to folder where you want to install express generator, open command prompt there and run this command
npm install express-generator, it will then fix the issue
I have tried out all above solutions, but its did't worked for me, finally I have re-installed the node.js with newer version and started to express install process again. Its worked for me.
npm install -g express
npm install -g express-generator
What command are you using to open the directory?
That error means CMD can't find the "express" executable in the current directory.
Use the "PUSHD" command or "CD /D" instead of "CD"
#Echo OFF
PUSHD "D:\myproject\express" || (Echo bad folder)
express.exe "site"
Pause&Exit
Express is loaded someplace else and not in the windows path environment variable. You need to find were express.exe is installed and add the path. Maybe something like ;"C:\Program Files\Express\bin";
Running "npm install express" and "npm install express-generator" from your project directory will resolve the issue (if that helps).
But, this doesn't solve the problem of being global.
You might check the permissions to the folder if you are getting this when creating your project
Express Project
change script section in package.json file like this
"scripts": {
"start": "node app.js"
}
I too faced the similar problem and at last I tried using node.js command prompt instead of windows command prompt and it worked. So, try from node.js command prompt.
Tried all of these but didn't work for me. Also, I tried from different sources but never worked for me.
In the end, found that I need to run the command forcefully. It worked for me.
Make sure you run the command with Run as Administrator.
npm install -g --force express-generator
It will overwrite the existing express files.
Use npm start .. then the app.js runs .. which can be listened on the usual port 3000

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