吞噬中的任务依赖性

Question

我试图使用以下gulpfile.js

const { watch, src, dest, parallel, series } = require('gulp')
const uglify = require('gulp-uglify')
const browserSync = require('browser-sync').create()
const htmlMin = require('gulp-htmlmin')
const cleanCSS = require('gulp-clean-css')
const imagemin = require('gulp-imagemin')
const hash = require('gulp-hash')                   // !!!
const references = require('gulp-hash-references')  // !!!
const del = require('del')
const path = require('path')

const manifestFile = 'asset-manifest.json'
const buildDir = './build'

function serve() {
    browserSync.init({
        server: {
            baseDir: "./"
        }
    })
    watch("./*.html").on('change', browserSync.reload)
    watch("./css/**/*.css").on('change', browserSync.reload)
    watch("./**/*.js").on('change', browserSync.reload)
}

function buildHTML(cb) {
    src('index.html')
        .pipe(references(manifestFile)) // replace file paths in index.html according to the manifest
        .pipe(htmlMin({
            collapseWhitespace: true
        }))
        .pipe(dest(buildDir))
    cb()
}

function buildCSS(cb) {
    src('./css/**/*.css')
        .pipe(cleanCSS())
        .pipe(hash())
        .pipe(dest(path.join(buildDir, 'css')))
        .pipe(hash.manifest(manifestFile)) // generate a manifest file
        .pipe(dest('.'))
    cb()
}


function buildJS(cb) {
    src(['./**/*.js', '!./node_modules/**', '!./gulpfile.js'])
        .pipe(uglify())
        .pipe(hash())
        .pipe(dest('build/'))
        .pipe(hash.manifest(manifestFile)) // generate a manifest file
        .pipe(dest('.'))
    cb()
}

function buildImages(cb) {
    src('./img/**/*.png')
        .pipe(imagemin([
            imagemin.optipng({ optimizationLevel: 7 })
        ]))
        .pipe(dest(path.join(buildDir, 'img')))
    cb()
}


exports.build = series(buildJS, buildCSS, buildHTML) // !!!
exports.default = serve

hash *.css和 *.js文件名，然后将其旧名称替换为build/index.html文件中的哈希名称。但是问题在于，函数“ buildhtml”开始工作早于创建的“资产 - manifest.json”文件。我在做什么错？

Answer 1

您必须返回您的功能创建的流以确保它们以预期顺序运行并捕获任何可能的错误。无需使用回调：

function buildHTML() {
    return src('index.html')
        .pipe(references(manifestFile)) // replace file paths in index.html according to the manifest
        .pipe(htmlMin({
            collapseWhitespace: true
        }))
        .pipe(dest(buildDir));
}

function buildCSS() {
    return src('./css/**/*.css')
        .pipe(cleanCSS())
        .pipe(hash())
        .pipe(dest(path.join(buildDir, 'css')))
        .pipe(hash.manifest(manifestFile)) // generate a manifest file
        .pipe(dest('.'));
}


function buildJS() {
    return src(['./**/*.js', '!./node_modules/**', '!./gulpfile.js'])
        .pipe(uglify())
        .pipe(hash())
        .pipe(dest('build/'))
        .pipe(hash.manifest(manifestFile)) // generate a manifest file
        .pipe(dest('.'));
}

function buildImages() {
    return src('./img/**/*.png')
        .pipe(imagemin([
            imagemin.optipng({ optimizationLevel: 7 })
        ]))
        .pipe(dest(path.join(buildDir, 'img')));
}