Not able to install express via npm [duplicate] - node.js

Question

When creating a new Angular 5 project:
node version: 8.9.2
npm version: 5.5.1
My Command is:
npm install -g #angular/cli
The Error is:
npm ERR! **Unexpected end of JSON input while parsing near '...nt-webpack-plugin":"0'**
npm ERR! A complete log of this run can be found in:
npm ERR! C:\Users\Aashitec\AppData\Roaming\npm-cache\_logs\2017-12-06T13_10_10_729Z-debug.log
The error log is here

Answer 1

This solved it for me:
Open Windows Powershell as admin
npm cache clean --force
npm install -g #angular/cli
https://devblogs.microsoft.com/premier-developer/getting-started-with-node-js-angular-and-visual-studio-code/

Answer 2

Solution:
npm cache clean --force
then try again to create your app (here when creating a react app) or install what you were about to install.
create-react-app myproject
(creating react app)[same npm problem that can occur in different operation]
npm install -g #angular/cli#latest
(installing angular cli (or installing anything else))
It will work.
explanation:
That's a problem related to npm, it's about the cache that get corrupt. Even though in newer versions of npm they implemented self healing, which normally guarantee no corruption, but it seem it's not that efficient.
Forcing clean cache resolve the problem.
The error happen when parsing one of the cache files, which have a json format. The cache is found at ~/.npm/_cacache (in linux) and %AppData%/npm-cache (windows). For my current npm version and when i checked, there was three directories.
if you check the first or the second, the structure is as follow
And each cache file have a json format (and that what get parsed)
Here a good link from the doc: https://docs.npmjs.com/cli/cache
[Update] Also if it happen that this didn't solve it, you may check this answer here https://stackoverflow.com/a/50191315/7668448 it show how you can change the npm registry, that can be helpful. Check and see.

Answer 3

If
npm cache clean --force
doesn't work.
try
npm cache clean --force
npm update

Answer 4

Npm uses Cache for downloading new packages for you.
You need to clear your npm cache.
use following command to clean :
npm cache clean --force
then normally use your npm install command
e.g.
npm install -g #angular/cli

Answer 5

I solve that with
npm cache clean --force
then update npm
npm i npm#latest -g
then normally use your npm install command
npm install

Answer 6

delete npm and npm-cache folders in C:\Users\admin\AppData\Roaming\ (windows)
then execute cmd
npm cache clear --force
npm cache verify
update npm to latest version
npm i -g npm
then create your project
1)Angular
npm i -g #angular/cli#latest
ng new HelloWorld
2)React
npm i -g create-react-app
create-react-app react-app

Answer 7

None of the 30 answers here worked for me. I needed to:
delete node_modules and package-lock.json
npm cache clean --force
npm install -g #angular/cli
npm i --package-lock-only
npm ci
Phew!

Answer 8

this solved it npm cache clean --force

Answer 9

Simple solutions:
npm cache clean --force
npm install

Answer 10

This command alone solved my problem:
npm cache clean --force
Also you should make sure you are using the correct version of node.
Using nvm to manage the node version:
nvm list; # check your local versions;
nvm install 10.10.0; # install a new remote version;
nvm alias default 10.10.0; # set the 10.10.0 as the default node version, but you have to restart the terminal to make it take effect;

Answer 11

I use Windows and removed all the files that were listed below and my problem was solved
C:\Users{{your-username}}\AppData\Roaming\npm-cache

Answer 12

npm cache clean --force worked for me
Error Resolved :
$ npm install -g gulp
npm WARN deprecated gulp-util#3.0.8: gulp-util is deprecated - replace it, following the guidelines at https://medium.com/gulpjs/gulp-util-ca3b1f9f9ac5
npm ERR! Unexpected end of JSON input while parsing near '.../RGs88STtAtiMP3tCiNdU'
npm ERR! A complete log of this run can be found in:
npm ERR! C:\Users\admin\AppData\Roaming\npm-cache_logs\2018-11-20T07_38_56_733Z-debug.log

Answer 13

Solution
npm cache clean --force
For Windows : go to C:\Users\username\AppData\Roaming\npm-cache
Delete all files and run
npm install && npm start

Answer 14

I solved that by first cleaning the cache using
npm cache clean --force
Then
npm install -g #angular/cli

Answer 15

My case - Windows 7 (had nothing better at the needed moment).
Helped me the following:
Deleting everything from C:\Users\username\AppData\Roaming\npm-cache
AND
Deleting package-lock.json

Answer 16

I resolved my problem with this one liner
npm cache clean --force
Note: since its a clean install, I had no concerns emptying npm cache.

Answer 17

ERROR: npm ERR! Unexpected end of JSON input while parsing near '...ore-js":"3.0.0-beta.1
This occurs when installing the expo CLI globally, This works for me!
npm cache clean --force

Answer 18

I got error (file already exists --force to overwrite) after running the following code:
npm cache clean --force
npm install -g #angular/cli
I solved it using :
npm i -g --force npm
Make sure to run the first commands to flush the cache of npm.

Answer 19

It's error from your npm....
So unistall node and install it again.
It works....
PS: After installing node again, install angular cli globally.
npm install -g #angular/cli#latest

Answer 20

I solve that with
First delete package-lock.json
npm cache clean --force
then update npm
npm i npm#latest -g
then use npm install command
npm install

Answer 21

If you looking for npm install and getting same kind of error
Delete package-lock.json and npm cache clean --force and try

Answer 22

In my case I changed the network to a much stronger one and npm install worked perfectly:
npm cache clean --force

Answer 23

If npm cache clean --force doesn't resolve the issue, try deleting the ~/.npm directory (*nix/macOS). This is the directory where node stores its cache, locks, logs, global packages (unless you're using nvm), and modules installed via npx.
First, backup your current ~/.npm directory:
mv ~/.npm ~/.npm-backup
Now try running your npm command again. This will create a new ~/.npm directory. If the issue is resolved, you can safely remove you backup. Before doing so, you may want to review the global packages installed in your ~/.npm-backup directory so you can reinstall them using npm i -g [package].
rm -rf ~/.npm-backup
If the issue is not resolved, you can restore your backup:
rm -rf ~/.npm
mv ~/.npm-backup ~/.npm
Careful with those rm commands, folks!

Answer 24

Instead of clearing the cache you can set a temporary folder:
npm install --cache /tmp/empty-cache
or
npm install --global --cache /tmp/empty-cache
As of npm#5, the npm cache self-heals from corruption issues and data extracted from the cache is guaranteed to be valid. If you want to make sure everything is consistent, use npm cache verify instead. On the other hand, if you're debugging an issue with the installer, you can use npm install --cache /tmp/empty-cache to use a temporary cache instead of nuking the actual one.

Answer 25

For me I had to clone my branch again and do npm install

Answer 26

You can use yarn package manager instead of npm.
It solved this problem for me

Answer 27

I've faced this issue and I tried all the answers on Stackoverflow but not worked for me, finally I found solution for this issue:
First of all you have to uninstall nodejs and remove all the files related him
Go to "Register Editor" and search for all "nodejs", "node.js" and delete them
Restart your computer
And reinstall nodejs then install angular.
It's worked for me

Answer 28

These commands worked for me
sudo npm cache clean --force
sudo npm cache verify
sudo npm i npm#latest -g

Answer 29

Try setting
npm config set strict-ssl false
and then try running,
npm install -g #angular/cli

Answer 30

This happens something due to cache or outdated version of Node Package Manager
i just updated my NPM it works fine
here is command to update Npm to latest version
npm i npm#latest -g
after updating NPM run your desired command