Editing NodeJS (section)

==Concept==
Node.js ist eine plattformübergreifende Open-Source-JavaScript-Laufzeitumgebung, die JavaScript-Code außerhalb eines Webbrowsers ausführen kann. 

 node -v // prints version

Node.js has a set of built-in '''modules''' which you can use without any further installation, Consider modules to be the same as JavaScript libraries (see <code>require</code> or <code>export</code>).

===npm===
'''npm''' (ehemals Node Package Manager) ist ein Paketmanager für die JavaScript-Laufzeitumgebung Node.js. Unter dem Namen npm Registry bzw. npm Open Source wird ein Repository betrieben, über das 350.000 Pakete (Stand 13. Januar 2017[4]) unter einer freien Lizenz bereitgestellt werden. npm is the world's largest software registry. Open source developers from every continent use npm to share and borrow packages, and many organizations use npm to manage private development as well.

npm consists of three distinct components:
* the website
* the Command Line Interface (CLI)
* the registry
Use the '''website''' to discover packages, set up profiles, and manage other aspects of your npm experience. For example, you can set up organizations to manage access to public or private packages. The '''CLI''' runs from a terminal, and is how most developers interact with npm. The '''registry''' is a large public database of JavaScript software and the meta-information surrounding it.

 npm -v // prints version
 
 npm -g install %Modulname // -g installs to standard directory C:\Users\U1728\AppData\Roaming\npm\node_module, see npm -g list
                        // if -g is missing it will install it to current directory .\node_modules, see 
npm list
 npm -s // save option, adds the package to dependencies in package.json

====package.json====
<code>package.json</code> holds important information about a project. It contains human-readable metadata about the project (like the project name and description) as well as functional metadata like the package version number and a list of dependencies required by the application. It is used by the npm CLI (and yarn) to identify your project and understand how to handle the project's dependencies. It's the  file that enables npm to start your project, run scripts, install dependencies, publish to the NPM registry, and many other useful tasks.
The scripts sections defines the commands which could be used by
 npm run <SCRIPT> 
e.g.
  "scripts": {
    "ng": "ng",
    "start": "ng serve",
    "build": "echo 'create build timestamp' && node ./src/environments/createBuildTimestamp.js && ng build",
    "watch": "ng build --watch --configuration development",
    "test": "ng test"
  },
oddly enough some scripts can be called directly by <code>npm <SCRIPT></code> but not the build script.

===Examples===
* see C:\Uwes\javascripts\test
====Test1====
* test1.js

 var http = require('http'); // use module http
 http.createServer(...).listen(8282)

 node test1.js // creates a http server which listens to port 8282

 http://localhost:8282 // netstat -a

===Installation===
The NPM program is installed on your computer when you install Node.js
* [[EDTLaptop2#Node.js|EDT Elitebook 2 EW10LAP1009143]]
* obsolete[[EDTLaptop1#NodeJS|EDT Elitebook]]