[node.js] Why does npm install say I have unmet dependencies?

I have a node package. When I run npm install from the package root, it installs a bunch of things, but then prints several error messages that look like this:

npm WARN unmet dependency /Users/seanmackesey/google_drive/code/explore/generator/node_modules/findup-sync/node_modules/glob requires graceful-fs@'~1.2.0' but will load

I must be confused about what exactly npm install does. If it detects a dependency, shouldn't it install it? Under what conditions does it give me error messages like this, and how can I resolve the dependencies?

It happened to me when the WIFI went down during an npm install. Removing node_modules and re-running npm install fixed it.

I fixed the issue by using these command lines

• $ rm -rf node_modules/
• $ sudo npm update -g npm
• $ npm install

It's done!

Upgrading NPM to the latest version can greatly help with this. dule's answer above is right to say that dependency management is a bit broken, but it seems that this is mainly for older versions of npm.

The command npm list gives you a list of all installed node_modules. When I upgraded from version 1.4.2 to version 2.7.4, many modules that were previously flagged with WARN unmet dependency were no longer noted as such.

To update npm, you should type npm install -g npm on MacOSX or Linux. On Windows, I found that re-downloading and re-running the nodejs installer was a more effective way to update npm.

The above answers didn't help me fully even after deleteting node_modules directory.

Below command helped me finally:

npm config set registry http://registry.npmjs.org/

Note that this pulls node modules over an insecure HTTP connection.

Src: https://stackoverflow.com/a/13119867/4082503

For every -- UNMET PEER DEPENDENCY, for ex. -- UNMET PEER DEPENDENCY [email protected], install that dependency with npm install --save [email protected] until you don't have any more UNMET DEPENDENCIES.

Good Luck.

I run npm list and installed all the packages listed as UNMET DEPENDENCY

For instance:

+-- UNMET DEPENDENCY css-loader@^0.23.1
npm install css-loader@^0.23.1

This solved it for me:

1. Correct the version numbers in package.json, according to the errors;
2. Remove node_modules (rm -rf node_modules);
3. Rerun npm install.

Repeat these steps until there are no more errors.

I encountered this problem when I was installing react packages and this worked for me: npm install --save <package causing this error>

In my case, the update of npm solved it.

sudo npm install -g npm

npm install will install all the packages from npm-shrinkwrap.json, but might ignore packages in package.json, if they're not preset in the former.

If you're project has a npm-shrinkwrap.json, make sure you run npm shrinkwrap to regenerate it, each time you add add/remove/change package.json.

I was trying to work on an automated deployment system that runs npm install, so a lot of these solutions wouldn't work for me in an automated fasion. I wasn't in a position to go deleting/re-creating node_modules/ nor could I easily change Node.js versions.

So I ended up running npm shrinkwrap - adding the npm-shrinkwrap.json file to my deployment bundle, and running installs from there. That fixed the problem for me; with the shrinkwrap file as a 'helper', npm seemed to be able to find the right packages and get them installed for me. (Shrinkwrap has other features as well, but this was what I needed it for in this particular case).

I had a similar issue while I was installing the React Native CLI. I wasn't sure which /node_modules directory I was supposed to remove after reading the answers here. I eventually just ran

npm update -g

and was able to install the package after that.

--dev installing devDependencies recursively (and its run forever..) how it can help to resolve the version differences?

You can try remove the node_moduls folder, then clean the npm cache and then run 'npm i' again

Some thing in the similar vein, I would add one other step.

Note that on npm version > 1.4.9, 'npm install' does install devDependencies. First try removing existing modules and cache:

remove node_modules $ rm -rf node_modules/
run $ npm cache clean

Then try:

npm install --dev
npm update --dev

This at least will resolve the recursive dependency resolution.

Take care about your angular version, if you work under angular 2.x.x so maybe you need to upgrade to angular 4.x.x

Some dependencies needs angular 4

Here is a tutorial for how to install angular 4 or update your project.

Updating to 4.0.0

Updating to 4 is as easy as updating your Angular dependencies to the latest version, and double checking if you want animations. This will work for most use cases.

On Linux/Mac:

npm install @angular/{common,compiler,compiler-cli,core,forms,http,platform-browser,platform-browser-dynamic,platform-server,router,animations}@latest typescript@latest --save 

On Windows:

npm install @angular/common@latest @angular/compiler@latest @angular/compiler-cli@latest @angular/core@latest @angular/forms@latest @angular/http@latest @angular/platform-browser@latest @angular/platform-browser-dynamic@latest @angular/platform-server@latest @angular/router@latest @angular/animations@latest typescript@latest --save

Then run whatever ng serve or npm start command you normally use, and everything should work.

If you rely on Animations, import the new BrowserAnimationsModule from @angular/platform-browser/animations in your root NgModule. Without this, your code will compile and run, but animations will trigger an error. Imports from @angular/core were deprecated, use imports from the new package

import { trigger, state, style, transition, animate } from '@angular/animations';.