I'm trying to run gulp
to build my app like Rob Dodson explains here,但我收到以下错误:
module.js:327 throw err; ^ Error: Cannot find module 'merge-stream' at Function.Module._resolveFilename (module.js:325:15) at Function.Module._load (module.js:276:25) at Module.require (module.js:353:17) at require (internal/module.js:12:17) at Object.<anonymous> (/Users/path/to/gulpfile.js:16:21) at Module._compile (module.js:409:26) at Object.Module._extensions..js (module.js:416:10) at Module.load (module.js:343:32) at Function.Module._load (module.js:300:12) at Module.require (module.js:353:17) at require (internal/module.js:12:17)
看来有一些名为merge-stream
的必需模块?它是否正确?如果是这样,我在哪里以及如何获得此模块?或者是否还有其他问题导致这种情况发生?
'use strict';
// Documentation on what goes into PolymerProject.
const path = require('path');
const gulp = require('gulp');
const mergeStream = require('merge-stream');
const del = require('del');
const polymerJsonPath = path.join(process.cwd(), 'polymer.json');
const polymerJSON = require(polymerJsonPath);
const polymer = require('polymer-build');
const polymerProject = new polymer.PolymerProject(polymerJSON);
const buildDirectory = 'build/bundled';
/**
* Waits for the given ReadableStream
*/
function waitFor(stream) {
return new Promise((resolve, reject) => {
stream.on('end', resolve);
stream.on('error', reject);
});
}
function build() {
return new Promise((resolve, reject) => {
// Okay, so first thing we do is clear the build
console.log(`Deleting build/ directory...`);
del([buildDirectory])
.then(_ => {
// Okay, now lets get your source files
let sourcesStream = polymerProject.sources()
// Oh, well do you want to minify stuff? Go for it!
// Here's how splitHtml & gulpif work
.pipe(polymerProject.splitHtml())
.pipe(gulpif(/\.js$/, uglify()))
.pipe(gulpif(/\.css$/, cssSlam()))
.pipe(gulpif(/\.html$/, htmlMinifier()))
.pipe(polymerProject.rejoinHtml());
// Okay now lets do the same to your dependencies
let depsStream = polymerProject.dependencies()
.pipe(polymerProject.splitHtml())
.pipe(gulpif(/\.js$/, uglify()))
.pipe(gulpif(/\.css$/, cssSlam()))
.pipe(gulpif(/\.html$/, htmlMinifier()))
.pipe(polymerProject.rejoinHtml());
// Okay, now lets merge them into a single build stream.
let buildStream = mergeStream(sourcesStream, depsStream)
.once('data', () => {
console.log('Analyzing build dependencies...');
});
// If you want bundling, do some bundling! Explain why?
buildStream = buildStream.pipe(polymerProject.bundler);
// If you want to add prefetch links, do it! Explain why?
// buildStream = buildStream.pipe(new PrefetchTransform(polymerProject));
// Okay, time to pipe to the build directory
buildStream = buildStream.pipe(gulp.dest(buildDirectory));
// waitFor the buildStream to complete
return waitFor(buildStream);
})
.then(_ => {
// You did it!
console.log('Build complete!');
resolve();
});
});
}
gulp.task('default', build);
答案 0 :(得分:1)
merge-stream
已经声明为devDependency
in package.json
,因此错误表明您尚未安装依赖项,或者以某种方式从依赖项存储中删除了该包(即{{1} }})。
要仅安装node_modules/
,您可以从项目的根目录运行此代码:
merge-stream
或:
npm install merge-stream
但是,通常需要为构建安装所有依赖项才能成功。改为运行:
yarn add merge-stream
或:
npm install