gulpfile.js

/* eslint-disable */
var gulp = require('gulp'),
    path = require('path'),
    ngc = require('@angular/compiler-cli/src/main').main,
    rollup = require('gulp-rollup'),
    del = require('del'),
    runSequence = require('run-sequence'),
    inlineResources = require('./tools/gulp/inline-resources'),
    jeditor = require("gulp-json-editor");

const rootPackageVersion = require('./package.json').version;
const rootFolder = path.join(__dirname);
const srcFolder = path.join(rootFolder, 'src');
const tmpFolder = path.join(rootFolder, '.tmp');
const buildFolder = path.join(rootFolder, 'build');
const distFolder = path.join(rootFolder, 'dist');

/**
 * 1. Delete /dist folder
 */
gulp.task('clean:dist', function () {
    return deleteFolders([distFolder]);
});

/**
 * 2. Clone the /src folder into /.tmp. If an npm link inside /src has been made,
 *    then it's likely that a node_modules folder exists. Ignore this folder
 *    when copying to /.tmp.
 */
gulp.task('copy:source', function () {
    return gulp.src([`${srcFolder}/**/*`, `!${srcFolder}/node_modules`])
        .pipe(gulp.dest(tmpFolder));
});

/**
 * 3. Inline template (.html) and style (.css) files into the the component .ts files.
 *    We do this on the /.tmp folder to avoid editing the original /src files
 */
gulp.task('inline-resources', function () {
    return Promise.resolve()
        .then(() => inlineResources(tmpFolder));
});


/**
 * 4. Run the Angular compiler, ngc, on the /.tmp folder. This will output all
 *    compiled modules to the /build folder.
 */
gulp.task('ngc', function () {
    return ngc({
        project: `${tmpFolder}/tsconfig.es5.json`
    })
        .then((exitCode) => {
            if (exitCode === 1) {
                // This error is caught in the 'compile' task by the runSequence method callback
                // so that when ngc fails to compile, the whole compile process stops running
                throw new Error('ngc compilation failed');
            }
        });
});

/**
 * 5. Run rollup inside the /build folder to generate our Flat ES module and place the
 *    generated file into the /dist folder
 */
gulp.task('rollup', function () {
    return gulp.src(`${buildFolder}/**/*.js`)
        // transform the files here.
        .pipe(rollup({
            // any option supported by Rollup can be set here.
            entry: `${buildFolder}/index.js`,
            external: [
                '@angular/core',
                '@angular/common'
            ],
            format: 'es'
        }))
        .pipe(gulp.dest(distFolder));
});

/**
 * 6. Copy all the files from /build to /dist, except .js files. We ignore all .js from /build
 *    because with don't need individual modules anymore, just the Flat ES module generated
 *    on step 5.
 */
gulp.task('copy:build', function () {
    return gulp.src([`${buildFolder}/**/*`, `!${buildFolder}/**/*.js`])
        .pipe(gulp.dest(distFolder));
});

/**
 * 7. Copy package.json from /src to /dist and add rootPackage version
 */
gulp.task('copy:manifest', function () {
    return gulp.src([`${srcFolder}/package.json`])
        .pipe(jeditor({
            'version': rootPackageVersion
        }))
        .pipe(gulp.dest(distFolder));
});

/**
 * 8. Copy README.md from / to /dist
 */
gulp.task('copy:readme', function () {
    return gulp.src([`README.MD`])
        .pipe(gulp.dest(distFolder));
});

/**
 * 9. Delete /.tmp folder
 */
gulp.task('clean:tmp', function () {
    return deleteFolders([tmpFolder]);
});

/**
 * 10. Delete /build folder
 */
gulp.task('clean:build', function () {
    return deleteFolders([buildFolder]);
});

gulp.task('compile', function () {
    runSequence(
        'clean:dist',
        'copy:source',
        'inline-resources',
        'ngc',
        'rollup',
        'copy:build',
        'copy:manifest',
        'copy:readme',
        'clean:build',
        'clean:tmp',
        function (err) {
            if (err) {
                console.log('ERROR:', err.message);
                deleteFolders([distFolder, tmpFolder, buildFolder]);
            } else {
                console.log('Compilation finished succesfully');
            }
        });
});

/**
 * Watch for any change in the /src folder and compile files
 */
gulp.task('watch', function () {
    gulp.watch(`${srcFolder}/**/*`, ['compile']);
});

gulp.task('clean', ['clean:dist', 'clean:tmp', 'clean:build']);

gulp.task('build', ['clean', 'compile']);
gulp.task('build:watch', ['build', 'watch']);
gulp.task('default', ['build:watch']);

/**
 * Deletes the specified folder
 */
function deleteFolders(folders) {
    return del(folders);
}