How to include Underscore.js in angular2 project built using angular-cli - angular2-cli

Question

I want to include underscore.js inside angular2 project built using angular-cli.
Till now I am unable to do so. I tried so far:
1- npm install underscore --save
2- tsd install underscore
3- script src="node_modules/underscore/underscore.js" , reference in index.html
4- inside system-config.js
/** Map relative paths to URLs. */
var map = {
'underscore': '../node_modules/underscore/underscore.js'
};
/** User packages configuration. */
var packages = {
'underscore': '../node_modules/underscore/underscore.js'
};
5- import * as _ from 'underscore';
But underscore.js is not getting copied in 'dist' directory during run-time , and browser complain of not finding underscore.js. I think I am missing something at Point#4.
Any help is much appreciated as I am beginning learning angular2.
Please remember that this project is made by angular-cli, and not by any other seed project. Other than Underscore.js, project is working fine.
[EDIT]
package.json has "underscore": "^1.8.3" in dependencies

Answer 1

Using Angular CLI 1.0.0-rc.1, the recommended solution is described here:
Angular2 2.4 How to load external libraries sush as Underscore into angular2.
npm install underscore --save // save to dependencies: required to run
npm install #types/underscore --save-dev // save to dev dependencies: required in dev mode
Then in your component class:
import * as _ from 'underscore';
...
subtitle = _.head(['xyz'])
Alternatively, there is another way to load "static" scripts in angular-cli as described here https://www.npmjs.com/package/angular-cli#global-library-installation:
In .angular-cli.json, add it to the scripts array:
"scripts": ["../node_modules/underscore/underscore.js"]
This will load underscore.js, but this is not a good way to make it available for use in your typescript classes.

Answer 2

install underscore using npm
Go to yourappname/src/typings.d.ts and add this line
declare module 'underscore';
then run ng build

Answer 3

Angular 2 full 3 file snippets
package.json
{
"name": "angular2-quickstart",
"version": "1.0.0",
"scripts": {
"start": "tsc && concurrently \"npm run tsc:w\" \"npm run lite\" ",
"lite": "lite-server",
"postinstall": "typings install",
"tsc": "tsc",
"tsc:w": "tsc -w",
"typings": "typings"
},
"license": "ISC",
"dependencies": {
"#angular/common": "2.0.0",
"#angular/compiler": "2.0.0",
"#angular/core": "2.0.0",
"#angular/forms": "2.0.0",
"#angular/http": "2.0.0",
"#angular/platform-browser": "2.0.0",
"#angular/platform-browser-dynamic": "2.0.0",
"#angular/router": "3.0.0",
"#angular/upgrade": "2.0.0",
"angular2-in-memory-web-api": "0.0.20",
"bootstrap": "^3.3.6",
"core-js": "^2.4.1",
"reflect-metadata": "^0.1.3",
"rxjs": "5.0.0-beta.12",
"systemjs": "0.19.27",
"tsd": "^0.6.5",
"underscore": "^1.8.3",
"zone.js": "^0.6.23"
},
"devDependencies": {
"concurrently": "^2.2.0",
"lite-server": "^2.2.2",
"typescript": "^2.0.2",
"typings": "^1.3.2"
}
}
systemjs.config.js
/**
* System configuration for Angular 2 samples
* Adjust as necessary for your application needs.
*/
(function (global) {
System.config({
paths: {
// paths serve as alias
'npm:': 'node_modules/'
},
// map tells the System loader where to look for things
map: {
// our app is within the app folder
app: 'app',
// angular bundles
'#angular/core': 'npm:#angular/core/bundles/core.umd.js',
'#angular/common': 'npm:#angular/common/bundles/common.umd.js',
'#angular/compiler': 'npm:#angular/compiler/bundles/compiler.umd.js',
'#angular/platform-browser': 'npm:#angular/platform-browser/bundles/platform-browser.umd.js',
'#angular/platform-browser-dynamic': 'npm:#angular/platform-browser-dynamic/bundles/platform-browser-dynamic.umd.js',
'#angular/http': 'npm:#angular/http/bundles/http.umd.js',
'#angular/router': 'npm:#angular/router/bundles/router.umd.js',
'#angular/forms': 'npm:#angular/forms/bundles/forms.umd.js',
// other libraries
'rxjs': 'npm:rxjs',
'underscore': 'npm:underscore',
'angular2-in-memory-web-api': 'npm:angular2-in-memory-web-api',
},
// packages tells the System loader how to load when no filename and/or no extension
packages: {
app: {
main: './main.js',
defaultExtension: 'js'
},
rxjs: {
defaultExtension: 'js'
},
'underscore':{
main: './underscore.js',
defaultExtension: 'js'
},
'angular2-in-memory-web-api': {
main: './index.js',
defaultExtension: 'js'
}
}
});
})(this);
tsconfig.json
{
"compilerOptions": {
"target": "es5",
"module": "commonjs",
"moduleResolution": "node",
"sourceMap": true,
"emitDecoratorMetadata": true,
"experimentalDecorators": true,
"removeComments": false,
"noImplicitAny": false
}
}
typings.json
{
"globalDependencies": {
"core-js": "registry:dt/core-js#0.0.0+20160725163759",
"jasmine": "registry:dt/jasmine#2.2.0+20160621224255",
"node": "registry:dt/node#6.0.0+20160909174046"
},
"ambientDependencies": {
"underscore": "github:DefinitelyTyped/DefinitelyTyped/underscore/underscore.d.ts#f0990e288ac73d593e982995947567aa2643b828"
}
}
1- npm install underscore --save
2- tsd install underscore (if tsd not install first install that)
3) now do npm install
4) then npm start

Answer 4

install underscore:
npm i underscore --save
in angular-cli.json:
"scripts": [
"../node_modules/underscore/underscore-min.js",
...
],
after run command:
ng build
in component:
declare var _: any;
#Component({...})

Answer 5

Do you have in your project a file called Package.json?
If Yes, you can try to add this line
"underscore": "^1.8.3",
in the dependencies of this file.
Modifications in system-config.ts
var map = {
"underscore": "node_modules/underscore",
};
var packages = {
'underscore': { main: 'index.js', defaultExtension: 'js' }
};
var packageNames = [
'#angular/common',
'#angular/compiler',
'#angular/core',
'#angular/http',
'#angular/platform-browser',
'#angular/platform-browser-dynamic',
'#angular/router-deprecated',
'#angular/testing',
'#angular/upgrade',
];
packageNames.forEach(function(pkgName) {
packages[pkgName] = { main: 'index.js', defaultExtension: 'js' };
});
var config = {
map: map,
packages: packages,
paths: {
"underscore": "/node_modules/underscore.js"
}
};
And to do a npm install after that.

Answer 6

I think you might have missed a step? Did you remember to setup underscore in the "angular-cli-build.js" file? This step tells clingon to put underscore in the vendor folder (/dist/vendor).
Here's how I got underscore working.
Install underscore and typings:
npm install underscore --save
typings install underscore --save --ambient
Setting up underscore in "angular-cli-build.js":
module.exports = function(defaults) {
return new Angular2App(defaults, {
vendorNpmFiles: [
'systemjs/dist/system-polyfills.js',
'systemjs/dist/system.src.js',
'zone.js/dist/**/*.+(js|js.map)',
'es6-shim/es6-shim.js',
'reflect-metadata/**/*.+(js|js.map)',
'rxjs/**/*.+(js|js.map)',
'#angular/**/*.+(js|js.map)',
'moment/moment.js',
'underscore/underscore.js'
]
});
};
Then underscore get compiled to the vendor folder (/dist/vendor), and now it's possible to point to this location from the system.config.ts file:
const map: any = {
"underscore": "vendor/underscore/underscore.js",
"moment": "vendor/moment/moments.js"
};
/** User packages configuration. */
const packages: any = {
'underscore': {
format: 'cjs'
},
'moment': {
format: 'cjs'
}
};
Remember to use the hole path including the .js hope this helps :)
I did the same as with moment, from the docs: https://github.com/angular/angular-cli/wiki/3rd-party-libs

Answer 7

I am using Angular-cli, all I did was to add this line in package.json
"underscore": "^1.8.3",
and then I Run:
1. npm install underscore --save
2. npm install
and it worked...