I'm writing a daemon script for Linux Debian, and I'd need to be able to access the $NVM_BIN shell environment variable, or somehow reference the path to the current "default" Node version as set in nvm.
Several of these daemon scripts will be running on the system.
Since all these scripts can share the same Node version, I'd like to reference some variable that gets automatically updated when I install a new version of Node and define it as "default", without having to manually change the Node JS reference in each script.
Is this possible?
Thanks!
I've finally found a way to do it.
The first line of the shell script must be:
#!/bin/bash
(part of the problems I had was related to the fact that my first line was #!/bin/sh instead)
Then, to access nvm variables or commands you must first source them with:
source <your_path>/nvm/nvm.sh
(where <your_path> needs to be replaced with the path to your nvm folder).
Now you can get the path to the node folder in two ways.
1. Through a standard nvm variable
$NVM_BIN
2. Directly "asking" to nvm
NVM_BIN=<your_path>/`nvm version`/bin/
Nice.
Related
I'm trying to write scripts that allow me to switch my development environment.
I want to write a script so that I can call it like this:
switchdevA
and inside that script, one of the things it should do is switch to node v16.16.0
inside switchdevA i have the following:
#!/bin/zsh
source ~/.zshrc
nvm use v16.16.0
the output says that I have switched to node v16.16.0, but when I type node -v I get:
v12.22.12
I can fix if i call source switchdevA, but should I do it that way? Other things like java don't seem to require me sourcing. In addition, the installation is lost if I start a new zsh session, ideally it should install for the current session and all future sessions.
What's the best practice around this?
A quick clarification: NVM is a shell function and not an executable.
You've correctly identified that source switchdevA will work properly, and that it is different from other version managers.
One solution is to keep your script as is, and create an additional shell alias that will run source scriptname (e.g. alias switchdevA='source switchdevA').
Unfortunately, for your other request to keep the current Node version in all future shell sessions, that can’t be achieved unless you have some persistence added in. For example, a simple file named ~/.lastnode. Then, in your ~/.zshrc, you would have a line nvm use "$(cat ~/.lastnode)" (which comes after the initialization of NVM). Finally, the original script would need to include a line at the bottom to update the last selected Node version: nvm version > ~/.lastnode.
I have no admin rights in my windows machine. Can I install NVM without admin rights? I tried using the environment variable path setup, but its not working in my case.
I have the same need and couldn't find one, so I created one base on another simple nvm:
https://www.npmjs.com/package/#jchip/nvm
Requires powershell 4+ and permission to execute scripts.
(You're talking about https://github.com/coreybutler/nvm-windows right?)
Whether you can install it without admin rights aside, the actual act of switching node versions with it requires them so you're going to have trouble.
Your best bet is to install different versions of node into different paths manually, and then configure your environment variables to point to the right one whenever you need to use it.
eg. prefix your cmd script with PATH=C:\node\v10;%PATH% to have any node or npm calls in that script use whatever node is sitting in v10
try this
create a bat file like below
#cd C:\Users\testuser\AppData\Roaming\nvm
#SET PATH=C:\Users\testuser\AppData\Roaming\nvm\v14.21.1;%PATH%
cd c:\users\testuser\Desktop\Project
#cmd.exe /K
Run bat file and type
code .
It's open with VSCode
go to the terminal and type node and you can see the node version that you set in the bat file.
enter image description here
You can apply any node version as above bat file
If you use Git Bash on Windows, you can add this to your bash.bashrc to switch node versions:
export PATH=/c/path/to/node/dir:$PATH
Then just restart your terminal to pick up the updated PATH.
It will prepend your path with your desired node version. It's the only way I've found to override the installed node version if you don't have admin rights on your machine.
I am trying to run the Swift compiler under Ubuntu. I followed this tutorial: https://itsfoss.com/use-swift-linux/ and everything seemed to work fine. I was able to run swift under Ubuntu.
However, when I closed the terminal, I was not able to run Swift anymore. The program was not found until I installed it again. I could not find any answers to this question as there aren't many people running Swift under Ubuntu.
It's not uninstalled, you just don't have the environment variables set up anymore, so Bash can't find the path to Swift. You can change that by exporting the appropriate environment variables in your .bashrc file.
When you followed the tutorial, you ran the following command:
export PATH=path_to_swift_usr_bin:$PATH
This command adds the path to the swift binary to your PATH environment variable. The PATH variable holds a list of places where Ubuntu will look for programs to run from the command-line. So if the Swift executable is not in one of the places listed in the PATH, your terminal will never find it.
There is a file in your home folder (the folder ~, which is an abbreviation for /home/username, where username is your username) named .bashrc, which runs whenever you open a new terminal window. If you need an environment variable to be available whenever you open the terminal, you should add the export line for that variable to your .bashrc.
In this case, your .basrhc should contain the same line above.
The important thing to remember is that your environment variables are not preserved between command-line sessions, so if you want to have an environment variable available every time you use the command-line, it needs to be defined in your .bashrc.
Issue is very peculiar, I have a version of NodeJS installed in Windows (in program files x86) and a newer version of software downloaded and exe is extracted.
The installed NodeJS (node.exe) 's path is included in system path variable. I added the extracted path to user environment path variable.
After doing my bit of RTFM I came to know that in case path variable both system and user environment variables are combined and the system gets the precedence.
Is there any way I can override (or nullify) the system variable's PATH with user variable's path ? or can the precedence of reading variables be changed ?
In cmd, type
set PATH=D:\Path_To_Local_Folder;%PATH%
node
It will start node from your local folder.
Using Powershell you can set the folder Node runs from so that it picks up the new version of Node for that instance of Powershell.
Open Powershell
Set the path variable to be your node folder
$env:Path = "C:\yournodefolder";
Running node --version should now display the version of node from your new folder.
I have a node webkit app, part of which involves using child processes in node to call pdftk (a separate command line program).
I don't want my users to have to install pdftk or use the command line, so I included pdftk in the packaged version of the node webkit app. If I run this packaged app from the command line, it works fine - and I assume that's because it's using the version of pdftk that's installed on my computer, not the one packaged with the app.
When I try to launch the app by double clicking on an icon in the gui, as I'd want a user to be able to do, I get a node.js error - child process ENOENT. I think that's because when launched through the gui, it doesn't inherit the environment variables (including PATH) from my command-line environment.
I know I can set environment variables as an option when I call the child process, but haven't been able to figure out how to do that correctly. I'm not sure what variable I should set, or what I should set it to. I suppose I'm not sure if it's even possible to call pdftk from within the packaged app, or if I would need to have the user install it on their own computer. Any help would be much appreciated.
I think this might not be about environment variables. I guess when you run from the command line your current working directory (CWD) is where the app is. And I think you set the path to pdftk relative to the node script. When you double click (a shortcut) the current working directory and the path where the node script is located are different so relative paths don't work as expected.
When you use relative paths, always use __dirname to get the path the node script is on and use it to set path to the pdftk file. The path.resolve function can be useful when doing this. Read path.resolve documentation
I strongly recommend you to check this question and answers
How do I get the path to the current script with Node.js?
What is the difference between __dirname and ./ in node.js?