我的应用程序完美运行并在localhost上构建。但是当它在Heroku上构建时，出现以下错误：
./src/index.js
Error: Cannot find module '@babel/plugin-proposal-decorators' from '/app'
at Array.map (<anonymous>)
那是我的package.json：
{
"name": "agroproject-ui",
"version": "0.1.0",
"private": true,
"dependencies": {
"@ckeditor/ckeditor5-build-classic": "^12.0.0",
"@ckeditor/ckeditor5-react": "^1.1.1",
"@fortawesome/fontawesome-svg-core": "^1.2.8",
"@fortawesome/free-solid-svg-icons": "^5.5.0",
"@fortawesome/react-fontawesome": "^0.1.3",
"@pluralsight/ps-design-system-actionmenu": "^3.1.10",
"@pluralsight/ps-design-system-badge": "^2.1.12",
"@pluralsight/ps-design-system-button": "^10.8.15",
"@pluralsight/ps-design-system-card": "^8.5.8",
"@pluralsight/ps-design-system-dropdown": "^0.5.3",
"@pluralsight/ps-design-system-layout": "^3.0.2",
"@pluralsight/ps-design-system-normalize": "^3.0.45",
"@pluralsight/ps-design-system-row": "^2.6.25",
"@pluralsight/ps-design-system-textinput": "^0.5.6",
"@svgr/webpack": "2.4.1",
"@tinymce/tinymce-react": "^3.0.1",
"axios": "^0.18.0",
"babel-eslint": "9.0.0",
"babel-jest": "23.6.0",
"babel-loader": "8.0.4",
"babel-plugin-named-asset-import": "^0.2.2",
"babel-preset-react-app": "^5.0.4",
"bfj": "6.1.1",
"case-sensitive-paths-webpack-plugin": "2.1.2",
"chalk": "2.4.1",
"css-loader": "1.0.0",
"dotenv": "6.0.0",
"dotenv-expand": "4.2.0",
"eslint": "5.6.0",
"eslint-config-react-app": "^3.0.4",
"eslint-loader": "2.1.1",
"eslint-plugin-flowtype": "2.50.1",
"eslint-plugin-import": "2.14.0",
"eslint-plugin-jsx-a11y": "6.1.2",
"eslint-plugin-react": "7.11.1",
"file-loader": "2.0.0",
"fs-extra": "7.0.0",
"glamor": "^2.20.40",
"google-maps-react": "^2.0.2",
"html-webpack-plugin": "4.0.0-alpha.2",
"identity-obj-proxy": "3.0.0",
"jest": "23.6.0",
"jest-pnp-resolver": "1.0.1",
"jest-resolve": "23.6.0",
"jsonwebtoken": "^8.4.0",
"mini-css-extract-plugin": "0.4.3",
"node-sass": "^4.9.4",
"optimize-css-assets-webpack-plugin": "5.0.1",
"pnp-webpack-plugin": "1.1.0",
"postcss-cssnext": "^3.1.0",
"postcss-flexbugs-fixes": "4.1.0",
"postcss-import": "^12.0.0",
"postcss-loader": "3.0.0",
"postcss-preset-env": "6.0.6",
"postcss-safe-parser": "4.0.1",
"prop-types": "^15.6.2",
"react": "^16.5.2",
"react-app-polyfill": "^0.1.3",
"react-aux": "^1.1.0",
"react-dev-utils": "^6.0.5",
"react-dom": "^16.5.2",
"react-redux": "^6.0.0",
"react-router": "^4.3.1",
"react-router-dom": "^4.3.1",
"react-table": "^6.8.6",
"redux": "^4.0.1",
"redux-thunk": "^2.3.0",
"resolve": "1.8.1",
"sass-loader": "7.1.0",
"style-loader": "0.23.0",
"terser-webpack-plugin": "1.1.0",
"url-loader": "1.1.1",
"webpack": "4.19.1",
"webpack-dev-server": "^3.2.1",
"webpack-manifest-plugin": "2.0.4",
"workbox-webpack-plugin": "3.6.2"
},
"scripts": {
"start": "node scripts/start.js",
"build": "node scripts/build.js",
"test": "node scripts/test.js"
},
"eslintConfig": {
"extends": "react-app"
},
"browserslist": [
">0.2%",
"not dead",
"not ie <= 11",
"not op_mini all"
],
"jest": {
"collectCoverageFrom": [
"src/**/*.{js,jsx}"
],
"resolver": "jest-pnp-resolver",
"setupFiles": [
"react-app-polyfill/jsdom"
],
"testMatch": [
"<rootDir>/src/**/__tests__/**/*.{js,jsx}",
"<rootDir>/src/**/?(*.)(spec|test).{js,jsx}"
],
"testEnvironment": "jsdom",
"testURL": "http://localhost",
"transform": {
"^.+\\.(js|jsx)$": "<rootDir>/node_modules/babel-jest",
"^.+\\.css$": "<rootDir>/config/jest/cssTransform.js",
"^(?!.*\\.(js|jsx|css|json)$)": "<rootDir>/config/jest/fileTransform.js"
},
"transformIgnorePatterns": [
"[/\\\\]node_modules[/\\\\].+\\.(js|jsx)$",
"^.+\\.module\\.(css|sass|scss)$"
],
"moduleNameMapper": {
"^react-native$": "react-native-web",
"^.+\\.module\\.(css|sass|scss)$": "identity-obj-proxy"
},
"moduleFileExtensions": [
"web.js",
"js",
"json",
"web.jsx",
"jsx",
"node"
]
},
"babel": {
"presets": [
"react-app"
]
},
"devDependencies": {
"@babel/core": "^7.4.3",
"@babel/plugin-proposal-class-properties": "^7.4.0",
"@babel/plugin-proposal-decorators": "^7.4.0",
"@babel/preset-env": "^7.1.6",
"redux-devtools": "^3.4.2",
"redux-devtools-extension": "^2.13.7",
"stylelint-config-airbnb": "0.0.0"
}
有人知道package.json可能有什么问题吗？
答案 0 :(得分：1)
您已将@babel/plugin-proposal-decorators包含在devDependencies中。
By default，Heroku安装您的dependencies和devDependencies，构建您的子弹，然后剥离您的devDependencies 。这是有道理的：在大多数情况下，devDependencies不应投入生产；用于开发而不是生产中需要的测试框架，编辑器插件等。
我建议将此模块移至您的dependencies，尽管另一种解决方案是通过设置NPM_CONFIG_PRODUCTION=false或YARN_PRODUCTION=false来tell Heroku not to prune your devDependencies，具体取决于您使用的工具
这两种方法都需要重新部署才能生效，除非您有明确的理由在Heroku上使用devDependencies，否则我强烈建议您使用前者。