How to test an npm package locally
If you want to develop your own npm package, you first have to test it locally.
I had this need with a project that I wanted to modularize.
I had a package I called, as an example, flaviocopes-common-database
.
I prepended flaviocopes-
to give it a unique namespace.
Inside the package I added a package.json
file with the module name in the name
property and a few dependencies:
{
"name": "flaviocopes-common-database",
"version": "1.0.0",
"description": "",
"main": "index.js",
"dependencies": {
"pg": "^8.0.2",
"sequelize": "^5.21.6"
}
}
Then I ran
npm link
This created a symbolic link in the /usr/local/lib/node_modules/
folder, that contains the global npm packages in the system, the ones installed using npm -g
, to be clear.
I had
/usr/local/lib/node_modules/flaviocopes-common-database
Pointing to the local file I had in
/Users/flavio/dev/code/flaviocopes-common-database
Now in another project I wanted to use this module, so I ran
npm link flaviocopes-common-database
and I was able to import it in the Node.js code using the usual require()
syntax:
const database = require('flaviocopes-common-database')
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