What is the practical difference between npm install and npm update? When should I use which?
The difference between npm install and npm update handling of package versions specified in package.json:
{
"name": "my-project",
"version": "1.0", // install update
"dependencies": { // ------------------
"already-installed-versionless-module": "*", // ignores "1.0" -> "1.1"
"already-installed-semver-module": "^1.4.3" // ignores "1.4.3" -> "1.5.2"
"already-installed-versioned-module": "3.4.1" // ignores ignores
"not-yet-installed-versionless-module": "*", // installs installs
"not-yet-installed-semver-module": "^4.2.1" // installs installs
"not-yet-installed-versioned-module": "2.7.8" // installs installs
}
}
Summary: The only big difference is that an already installed module with fuzzy versioning ...
gets ignored by npm install
gets updated by npm update
Additionally: install and update by default handle devDependencies differently
npm install will install/update devDependencies unless --production flag is added
npm update will ignore devDependencies unless --dev flag is added
Why use npm install at all?
Because npm install does more when you look besides handling your dependencies in package.json.
As you can see in npm install you can ...
manually install node-modules
set them as global (which puts them in the shell's PATH) using npm install -g <name>
install certain versions described by git tags
install from a git url
force a reinstall with --force
npm install installs all modules that are listed on package.json file and their dependencies.
npm update updates all packages in the node_modules directory and their dependencies.
npm install express installs only the express module and its dependencies.
npm update express updates express module (starting with npm#2.x, it doesn't update its dependencies).
So updates are for when you already have the module and wish to get the new version.
In most cases, this will install the latest version of the module published on npm.
npm install express --save
or better to upgrade module to latest version use:
npm install express#latest --save --force
--save: Package will appear in your dependencies.
More info: npm-install
npm update: install and update with latest node modules which are in package.json
npm install: install node modules which are defined in package.json(without update)
Many distinctions have already been mentioned. Here is one more:
Running npm install at the top of your source directory will run various scripts: prepublish, preinstall, install, postinstall. Depending on what these scripts do, a npm install may do considerably more work than just installing dependencies.
I've just had a use case where prepublish would call make and the Makefile was designed to fetch dependencies if the package.json got updated. Calling npm install from within the Makefile would have lead to an infinite recursion, while calling npm update worked just fine, installing all dependencies so that the build could proceed even if make was called directly.
Related
I have a Node.js project which has several dependencies.
I created the package.json file (npm init)
and try to install all the relevant packages
(npm install all) or (npm install)
with npm install I'm getting the following result:
npm notice created a lockfile as package-lock.json. You should commit this file.
but
when I'm trying to run, I'm getting error that a package is missing (i.e express and I need to install it manually)
Is there a way (command) to install at once (with one command) all the relevant packages and dependencies ? (instead of install each of the package manually) ?
Update 1:
I think I found the solution to your problem, you can use this npm module for auto installing your dependencies.
Install
npm install -g auto-install
Usage
Run auto-install in the directory you are working in.
So npm is simple!
you can add a single package using npm install package-name
or
you can install all using npm install, this will read your package.json file and install all the packages which are in there
Additionally you can do this:
npm install package1 package2 package to install multiple packages.
If a required dependency is not installed, just install it once manually using npm's --save argument and it will automatically add that dependency to your package.json.
For instance, if you are missing the express dependency, just run:
npm install --save express
That will install the dependency in your node_modules folder and also automatically update your package.json file to include express. On subsequent installs on different machines, you'll now only need to run npm install and the express package will be added automatically.
Update with a little more context: In Node your package.json file defines all dependencies that are required for your project. However, these dependencies are not automatically generated for you. npm init will create a boilerplate package.json, but it will not fill that package.json with any dependencies.
You need to define the dependencies yourself, which you can do one of two ways:
Manually add lines to your package.json's dependencies section
Use npm install --save <package name> to have npm install a package and automatically save that package as a dependency in your package.json file
If you aren't familiar with package.json files, I'd recommend sticking to approach number 2 so that npm handles editing that file for you.
Once you have a package.json with all of the dependencies you need, then when you pull down your project onto new machines you will be able to automatically install all dependencies at once using a simple npm install command. You can test this on your own machine by deleting the node_modules folder and running npm install, then trying to run your project. If it runs fine then you successfully added all dependencies to your package.json. If it complains about a missing package then add that package with npm install --save <package>
Following this question, NPM dependencies can be installed using:
$ npm install --ignore-scripts
Is there a way to mark that a dependency should be installed without running scripts in package.json?
This is because, when I run npm install --ignore-scripts, the dependency is added to package.json. As a result, other users will install the package while running scripts, however I want this certain package to never run scripts.
I could be wrong but I believe its: npm install -ignore-script package-name#version
If I update the package.json file in an NPM workflow app, what command do existing users run to update their local node_modules dependencies?
To start using it, they run:
$ npm install
So what do they run if there is a change to the package.json file? Or do they just delete the folder and re-run the npm install command?
To re-validate the package.json and install adjusted versions or new packages:
$ npm install
The one thing this won't do is remove packages that aren't in package.json. To do that, run:
$ npm prune
If you've only changed package versions and not added new packages:
$ npm update
If you you've updated a specific package version:
$ npm update {packagename}
You should either do
npm install && npm prune
or
npm upgrade && npm prune
npm install will be faster than npm upgrade because it only updates packages in node_modules if package.json demands a newer version. npm uprade, on the other hand, will download updates to dependencies if they are available, which may include bug fixes. For ≥npm-5, you should use npm install because npm upgrade will have the side-effect of modifying any package-lock.json file which should not be modified unless if you are the package’s maintainer.
npm prune is necessary because the updates to package.json may have removed dependencies. If you do not run npm prune, packages installed by a prior version of package.json will remain in the node_modules directory that would not be there if you freshly downloaded/cloned the project and ran npm install. Due to how some packages conditionally call require() or even scan the node_modules directory, leaving packages which were removed from package.json can result in unexpected behavior.
I'd like to install npm modules based on package.json
I'd like to know if there is anyway to automate installing modules.
For instance dependencies of package.json is as follows.
"dependencies": {
"express": "3.1.0",
"jade": "*",
"stylus": "*",
"mongodb": ">= 0.9.6-7"
}
do I have to install modules one by one like this?
npm install express#3.1.0
npm install mongodb#0.9.6
and etc.
Any help would be appreciate.
See the documentation about npm install.
By default, npm install will install all modules listed as dependencies in package.json.
So you can just type npm install.
when you are installing first time use --save, that module installation info will be added to package json
after that at new location you just need to run npm install
npm install express#3.1.0 --save
npm install mongodb#0.9.6 --save
npm install
also refer link
You can do this by typing:
sudo apt-get update
sudo apt-get install npm
use nvm to switch versions.
If you want to install a specific version of module you should use
npm install module_name#version --save
--save add's the module and the version of the module to your package.json file's dependencies. If you want to install just any version of a module you can use
npm install module_name --save
if you don't use --save at the and node would still install the last version of the module you want but it wouldn't add it to your package.json file . In this case you have some specific versions of some modules in your package.json file if you want to install them, you can simply use the
npm install
command. npm install installs all modules in your package.json file.
Also if you are new in nodeJs you can check this out. I hope this helps. Have a good day good sir.
You could install modules written in package.json as follows.
npm install
I used nvm to download node v0.4.10 and installed npm to work with that version of node.
I am trying to install express using
npm install express -g
and I get an error that express requires node version >= 0.5.0.
Well, this is odd, since I am following the directions for a node+express+mongodb tutorial here that used node v0.4.10, so I am assuming express is/was available to node v0.4.10. If my assumption is correct, how do I tell npm to fetch a version that would work with my setup?
If you have to install an older version of a package, just specify it
npm install <package>#<version>
For example: npm install express#3.0.0
You can also add the --save flag to that command to add it to your package.json dependencies, or --save --save-exact flags if you want that exact version specified in your package.json dependencies.
The install command is documented here: https://docs.npmjs.com/cli/install
If you're not sure what versions of a package are available, you can use:
npm view <package> versions
And npm view can be used for viewing other things about a package too. https://docs.npmjs.com/cli/view
It's quite easy. Just write this, for example:
npm install -g npm#4.6.1
Or:
npm install -g npm#latest // For the last stable version
npm install -g npm#next // For the most recent release
First remove old version, then run literally the following:
npm install express#3.X
or
npm install express#4.X
and for stable or recent
npm install -g npm#latest // For the last stable version
npm install -g npm#next // For the most recent release
In my opinion that is easiest and fastest way:
$ npm -v
4.2.0
$ npm install -g npm#latest-3
...
$ npm -v
3.10.10
you can update your npm package by using this command:
npm install <package_name>#<version_number>
example:
npm install yargs#12.0.2
You can use the following command to install a previous version of an npm package:
npm install packagename#version
I have a general way to solve this type of problems, which could be helpful too, especially when cloning repositories to run them locally, but requires a little more analysis of the versions.
With the package npm-check-updates I verify the versions of the packages (according to the package.json file) that are not declared in their latest available versions, as shown in the figure (https://www.npmjs.com/package/npm-check-updates):
With this information we can verify the update status of the different packages and make decisions as to which packages to upgrade / degrade and which ones do not.
Assuming that we decided to update all the packages as they are listed, we can use the ncu -u command which only modifies your package.json file. Run npm install to update your installed packages and package-lock.json.
Then, depending on the requirements of the repository, we can refine what is needed, installing the specific versions with
npm view <package> versions and npm install <package>#<version>
The easiest way I found: add package name with the version in package.json and then run npm install
"next-seo": "^5.4.0",
"next-themes": "^0.1.1",
"nextjs-progressbar": "^0.0.14",
If you have to install an older version of a package, just specify it
npm install #
For example: npm install express#3.0.0
You can also add the --save flag to that command to add it to your package.json dependencies, or --save --save-exact flags if you want that exact version specified in your package.json dependencies.
The install command is documented here: https://docs.npmjs.com/cli/install
If you're not sure what versions of a package are available, you can use:
npm view versions
And npm view can be used for viewing other things about a package too. https://docs.npmjs.com/cli/view
Use npm config set save-exact=true if you want to install the exact version