I have an interesting question. let us say that I'm going on a holiday where I don't have access to the internet. I happen to bring my laptop with me so that I can write some code. Me being an idiot or smart depending on perspective, I usually install my node modules using the global flag. I suspect that this adds the module locally.
My Question.
Is it possible to npm install a module locally installed into a new project without having access to the internet?
if so, what command does one run?
This is another way.
You will need to use the npm install command with the --offline flag, like this:
npm install --offline \<nameOfModule>
Related
I am in a unique situation where I can run npm install only on a linux based machine even though I plan to run my electron/node application on an offline Windows machine.
So, is there a way to tell npm to perform an install and "trick" it to npm install the windows version of each module?
I understand most modules are based on javascript and are not native, but a few are dependent on operating system, such as electron itself.
Perhaps I could modify any header information npm sends out which tells the servers which operating system I am running?
So, is there a way to tell npm to perform an install and "trick" it to
npm install the windows version of each module?
No. If you want NPM to install for windows, then you have to run NPM on windows.
For pure Javascript modules, you could "probably" install for Linux and then just copy the directories over to windows, but you'd have to know that these were pure Javascript modules that contained no native code and did not use any binaries or compile any native code and copying directories behind the back of NPM is asking for it to be confused about what you have.
It sounds like perhaps you should explore fixing whatever issue is keeping you from running NPM on your windows box directly.
I just setup a test, and tried to npm install express even though express already exists globally on my system. To my surprise, instead of using the global version, it ended up re-installing a version locally!? Isn't it supposed to use the global version... Or am I suppose to use -g every time, even when I only want to use the existing global version. Otherwise, what's the point of installing anything locally!?
The answer is "NO". It isn't supposed to use your global version.
If you want to use your global version, then you doesn't need to execute npm install at all because it is already installed.
If you do it then, obviously, you are saying "I want to install it locally to my project". And more than that: "I want to install its latest version unless it is declared in my package.json with other explicitly specified version".
In fact, the actual question is: Why in the hell would you want to not install a dependency of your project locally? To have more version mismatch issues?
As #anshuman_singh says, best practice is to always do an npm install --save.
You are able to use globally installed packages, of course. It could be handy for fast testing code that you will drop just after a few hours or so.
But, anyway: If you doesn't have really hard disk or network bandwidth issues, installing all dependencies locally will avoid you too much trouble in the future.
On the other hand, uploading that modules to your code repository is also a bad idea (maybe that is what you were trying to avoid) because, with different versions of node, most native modules won't work if not rebuild. But most VCS support ignoring files and or directories that must not be uploaded.
For example, in git (.gitignore file):
**/node_modules
In summary:
npm init (if you didn't already it).
npm install --save for all your project dependencies.
npm install --save-dev for dependencies not needed in production (testing stuff).
Don't upload node_modules to your VCS.
After new checkout: npm install or npm install --production (to not install dev-dependencies).
npm install -g only for tools you will use in console.
This way, you are sure that you will have in production (or other dev environments) the exact same version of each package.
And, finally, if you ever want to upgrade some package to its latest version, simply run:
npm install --save <pagkage_name>#latest.
If you’re installing something that you want to use in your program, using require('whatever'), then install it locally, at the root of your project.
If you’re installing something that you want to use in your shell, on the command line or something, install it globally, so that its binaries end up in your PATH environment variable.
The first option is the best in my opinion. Simple, clear, explicit. The second is really handy if you are going to re-use the same library in a bunch of different projects
Install locally-
npm install moduleName
install locally and save in package.json-
npm install moduleName --save
install globally-
npm install moduleName -g
I have used to install my nodejs on D:\ drive instead of C and have set environment variables to D drive node & npm folders.
Then i changed npm installation path as "prefix=D:\node\node_modules\npm
" on "npmrc" file. So i could confirm that all user based modules are pointing on D drive npm folder instead of appdata.
I tried to install express js globally and i used to check the package tree on my cli as mentioned below,
npm ll -g
while trying this command am getting npm extraneous ERR,
Please suggest me that which way i have to use npm path and installation stuffs.
Thanks in advance.
It might seem like a good idea to install packages globally, but this is one great reason not to.
Often used packages like express, and cookies should be kept local to a package. Mostly because of versioning issues. You might have one package using express2, but your new one wants to use express3. You would have trouble if it was a global install. When in doubt leave off that -g, and use a --save instead. (This adds the package to your npm dependencies list.)
On the other hand, command line tools like mocha, yeoman, and uh not much else that I know of should be installed with the -g flag.
I'm not much of a windows person, so you'll have to look a little yourself, but I would also recommend not installing Node by hand, but instead using a version manager like nvm to do that stuff. Here's an nvm port for windows: https://github.com/coreybutler/nvm-windows
Hello I am just a noob and still learning. I have already downloaded and tried the chat tutorial of get-started part from socket.io. Now, I am again learning from another source. What's confusing me is that, do I always have to npm install in the beginning of every project after writing the dependencies in the package.json? Or is there any other way? I would be very glad if you could help me understand my confusion. Thank you!
Yes, before running, all dependencies must be installed. So you must run npm install.
When developing, you can use npm install --save <package_name> to install a dependency and automatically add it to package.json.
NPM means Node Package Manager. It is used to manage your dependencies to other node modules dynamically thanks to a configuration file called package.json. This way you can easily define the exact versions you need or a mask in order to always retrieve the stable ones for instance.
The command npm install allows to interpret your configuration file and then download the good versions (and this recursively).
I have recently started playing with node.js, but I got lost in a big mess of different versions of node, npm, nvm and other packages. I don't know what is installed globally and what is installed locally (and if locally, how do the packages know which versions of node they can use?).
I'd like to have some summary of what different installation options do. In specific:
Where is node installed when I use nvm, apt-get, make install or when using other ways?
Is it a good idea to install node locally?
Why does nvm change my ~/.profile instead of installing itself in some system-recognizable bin folder?
I saw that nvm can install different versions of node alongside each other - why would I want to do this? I can install them locally instead, right?
Where does npm install packages? I saw that it checks packages aganist version of Node, what happens to these packages when node is upgraded?
In what cases it is better to use global or local installation? Where should I put my packages then (and where they put by default?)
What's the difference between npm, nvm and nave?
EDIT: There is a lot of ways to install node here, this makes me even more confused...
Where is node installed when I use nvm, apt-get, make install or when
using other ways?
apt-get installs all the software, not only node, on the file system following the Ubuntu convention where to store binaries, man files, shared files, logs, etc. However, using apt-get you'll have only the certain version of node which is determined by the distribution release cycle. If there are updates available they will be installed with apt-get update; apt-get upgrade However, the newest version of some app won't be available until it makes its way into the distribution. For example node v0.x.y might not be available until Ubuntu 13.10 the only way to get will be to install it manually. The good side of apt-get or other system package manager is that it manages updates and package removal for you. It stores all the data about the software package in it's own database. You can always delete the node with apt-get remove node and that's it.
make install install the package manually, but it is considered harmful. Never use the make install mainly because you won't be able to delete the package easily, you'll have to read the Makefile and manually delete all the files installed by it. In a situation where you want to use make install there is always checkinstall available. It's a software which creates a native package and registers it with the system. When you decide to delete the package you could do this with one command instead of many. wiki link; Ubuntu guide on checkinstall
Now nvm script is a node version manager. It is very helpful and easy to use. It allows you to have multiple versions of node to be installed and used in parallel on your machine. It doesn't compile the node from source like make install so it is very fast. it doesn't depend on your distribution release cycle so you have access to all the node versions available at the moment. nvm downloads precompiled binaries and is perfect for general use. It stores it's node files in it's own folder locally so in case you want to compare something between the different node versions it's easy to do.
Is it a good idea to install node locally?
If by locally you mean using nvm then it's very good for development, and testing. Not sure about production performance implications and benefits between having it's installed from source or using the nvm precompiled binaries. I use nvm for development and installed from source in production. However if someone could explain this issue any further I'll be glad to learn more.
Why does nvm change my ~/.profile instead of installing itself in some system-recognizable bin folder?
Because nvm isn't an executable. It is a set of bash functions which are sourced by shell and could be used separately. You can invoke nvm_ls and nvm_ls_remote and others without the main script after is is sourced into your shell. What the main script does it parses the command line arguments and pretty prints the output in case of for example `nvm_ls_remote'.
in the ~/.profile the following line is added
[[ -s /home/USERNAME/.nvm/nvm.sh ]] && . /home/USERANME/.nvm/nvm.sh # This loads NVM
loads all the functions into your shell
I saw that nvm can install different versions of node alongside each other - why would I want to do this? I can install them locally instead, right?
You can install them locally using make install or checkinstall but you will have to make aliases for them like node_0.8.1, node_0.8.2, node_0.10.1 , etc. AND you'll have to manage new aliases, installing all the packages, removing them in case you don't need them YOURSELF. These are a tedious and boring tasks which could be error prone sometimes. nvm does all of these tasks for you for free.
You want to do this to test your app under the different versions of node. For example you are good and tested under the v0.8 but you want to use the new features of the v0.10.3 how do you do that ? You have to download the source code, compile, make an alias and run your app. you could do this with just nvm install 0.10.3 and run your app.
Sometimes you have to support more than one version of node. For example some hosted environments are not keeping in touch with the latest release and only have v0.6 Your clients which use your server app might encounter a bug specific to this version. When you fix the bug you have to reproduce it first. Using nvm installation of the v0.6 is one line and half a minute. And you can check all the versions you want this way easily. Test your code under different versions and make sure you are good to go.
Where does npm install packages? I saw that it checks packages aganist version of Node, what happens to these packages when node is upgraded?
If you are using nvm the packages which are installed globally with -g option are tied to the relevant node version. When you switch between versions with nvm use 0.x you have to either install the packages again or use nvm copy-packages <version> to use the packages from in the current version. If the packages are installed locally then it depends. package.json should contain info on the dependencies of the app. If it says node: '0.8' and you just updated to 0.9 you might encounter troubles. For example the behavior of process.nextTick was changed in the latest releases compared to 0.6. So be careful.
In what cases it is better to use global or local installation? Where should I put my packages then (and where they put by default?)
It depends. For development nvm is superior in my opinion. For me it is convenient and simple. For production there are might be some performance implications when using the precompiled binary files not optimized for your system. It would be better to ask this as a separate question so the people with the relevant experience could answer.
What's the difference between npm, nvm and nave?
npm is a node package manager -> link It contains userland packages developed by other people. These packages are not part of the node core. npm is used for publishing your code and dependency management. If your app requires other app developed by other people it is convenient to publish it via npm.
nvm is a node version manager it does a completely separate thing. It gives you an ability to very easily switch between node versions on the same machine and manages all he changes in your $PATH environment variable.
Consider nvm as update manager for the Operation System and npm as a manager of the applications for this system. Well, this comparison isn't precise but just came upon my mind
nave is basically the same as nvm but it is an executable whereas nvm is a script which is sourced into the shell. Each system has it's own benefits. You could make a separate question regarding it's use cases and differences.
My answer isn't 100% complete and contains a lot of subjective personal opinions. However, I hope I'll at least make some points more clear so you might proceed with other more specific questions. Btw, this question list of yours could be asked as separate questions. I believe stackoverflow gives best results when specific questions are asked separately and more people with relevant experience could contribute.
If you run
npm install
in folder with package.json, it installs all packages localy (in the current folder).
Also, npm default install packeges local. To install it globaly - use -g flag:
npm install -g <package>
Execute next command:
npm config list
You see all npm config description.
You can install modules in the local context of your application with
npm install modulename
In this case the module will be installed to your node_modules folder of your application.
Otherwise you can install a module in the global context with
npm install -g modulename
In this case the module will be installed for the hole system environment usually at /usr/local/bin/modulename.
The global installation makes sense for modules you need in more than one application, like express or node-inspector.