Slides link
As we are going to publish packages into npm and we don't want to polute our company account, start by logging out:
npm logout
Login back into npm:
npm login
Checkout that you are logged in as npm-workshop
by executing
npm whoami
We want to publish our addition module, therefore we need a package.json
file. Create one.
After it's done, change the name
property inside the package.json file in order to avoid collitions. For example, use your name initials (Bart Simpson would rename the package as addition-module-bs
)
We want to make sure that our test are working (npm run test fails right now). Install the jest
dependency, which is our chosen javascript testing framework and edit the test script so it launches jest
.
Bonus: run jest without using
npm run
After installing your fist dependency, the node_modules
folder and the package-lock.json
file have been created. Check what jest
version has been installed without opening the package.json
file
After being able to check that our test works we feel confident enough to publish our first npm module. Checkout the log after running npm publish
Create a new project, execute npm init -y
, install your recent published package and create a index.js
file that requires the addition-module and uses it. Run it and checkout that it works
Add a new call to adds a third param to our exported function. Iterate our addition package so it is able to add 3 arguments. Link the packages so you are able to test it locally
Bonus: check out what happens if you unlink the
addition-module
and run you code
Publish the recent changes to your addition-module as beta
and install this version in your new module
npm init -y
Change the name to addition-module-[your name initials]
{
"name": "addition-module-jg",
"version": "1.0.0",
"description": "",
"main": "sum.js",
"scripts": {
"test": "echo \"Error: no test specified\" && exit 1"
},
"repository": {
"type": "git",
"url": "git@github.mpi-internal.com:julian-gernun/workshop-npm.git"
},
"keywords": [],
"author": "",
"license": "ISC"
}
npm i --save-dev jest
Modify the test script inside the package.json file
{
"name": "addition-module-jg",
"version": "1.0.0",
"description": "",
"main": "sum.js",
"scripts": {
"test": "jest"
},
"repository": {
"type": "git",
"url": "git@github.mpi-internal.com:julian-gernun/workshop-npm.git"
},
"keywords": [],
"author": "",
"license": "ISC",
"devDependencies": {
"jest": "^26.1.0"
}
}
npm run test
// runs jest test
Bonus
npx jest
npm ls jest
mkdir new-module
cd new-module
npm init -y
npm install addition-module-jg
// index.js
const sum = require("addition-module-jg");
console.log(sum(1, 2));
// output: 3
// package.json
{
"name": "use-addition-module",
"version": "1.0.0",
"description": "",
"main": "index.js",
"scripts": {
"test": "echo \"Error: no test specified\" && exit 1"
},
"keywords": [],
"author": "",
"license": "ISC",
"dependencies": {
"addition-module-jg": "^1.0.0"
}
}
// index.js
const sum = require("addition-module-jg");
console.log(sum(1, 2, 3));
// output: 3
npm link # in the addition-module-jg folder
npm link addition-module-jg # in our new module folder
node index.js
// output: 6
Bonus
npm unlink addition-module-jg
Execution breaks as the package has been removed completely
npm version 1.0.0-beta.0 # in the addition-module-jg folder
// new module's package.json
{
...
"dependencies": {
"addition-module-jg": "beta"
}
}
npm install # in the new module's folder