Strip dynamic requires from webpack - javascript

I have a code similar to this:
export default {
something: true,
mockData: process.env.USE_MOCK && require('./mocks/something.js').default
};
process.env.USE_MOCK is set with webpack.DefinePlugin to either true or false. I use this to start my app with USE_MOCK=true npm run dev or npm run dev to either run with mock data or not.
I want Webpack to remove these dynamic require in the build process with UglifyJS' dead code elimination, but I noticed that they remain there and so something.js will be in the built bundle.
In my case the output is similar to:
module.exports = {
something: true,
mockData: (false) && __webpack_require__(181).default
};
Is there a way how I can remove that import completely from the bundle?
Btw. I think something like this works:
let mockData;
if (process.env.USE_MOCK) {
mockData = require('./mocks/something.js').default;
}
export default {
something: true,
mockData
};
I'd prefer the inline require though, as I've got that pattern quite a few times.

Try something like this:
export default {
something: true,
mockData: process.env.USE_MOCK ? require('./mocks/something.js').default : undefined
};
Or build module export separately:
let module_export;
module_export.something = true;
if (process.env.USE_MOCK) {
module_export.mockData = require('./mocks/something.js').default;
}
export module_export;

Related

Error with WEB3js - NodeJs.utils in vite react ts app - How to resolve TypeError: callbackify is not a function

Hey I am playing around with web3 inside react as a client application (using vite react-ts) and trying to call web3.eth.net.getId() but this will throw me an error that callbackify is not a function I digged a little and found an old issue on the github which states that older versions of Nodejs.util (prior version 0.11) didn't have this function. So I checked the package.json where the error occurs (web3-core-requestmanager) it has "util":"^0.12.0", so callbackify should be available.
In fact when I am looking at their imports, they seem to be able to import it:
(following code is ./node_modules\web3-core-requestmanager\src\index.js
const { callbackify } = require('util');
but when they want to use it, callbackify is undefined
//RequestManager.prototype.send function
const callbackRequest = callbackify(this.provider.request.bind(this.provider));
I tried to play around with the dependencies and tried different versions of web3.js (1.7.3; 1.6.0; 1.5.1) all of them had the same util dependency (0.12.0).
My code in all this matter looks like this:
class Blockchain {
public blockchainBaseUrl: string;
public web3;
public provider;
public account: string = '';
public contract: any;
constructor() {
if (process.env.REACT_APP_BLOCKCHAIN_BASE_URL === undefined) {
throw new Error('REACT_APP_BLOCKCHAIN_BASE_URL is not defined');
}
this.provider = window.ethereum;
if (this.provider === undefined) {
throw new Error('MetaMask is not installed');
}
this.setUpInitialAccount();
this.addEthereumEventListener();
this.blockchainBaseUrl = process.env.REACT_APP_BLOCKCHAIN_BASE_URL;
this.web3 = new Web3(Web3.givenProvider || this.blockchainBaseUrl);
this.setContract();
}
async setContract() {
// error comes from the next line
const networkId = await this.web3.eth.net.getId();
this.contract = new this.web3.eth.Contract(
// #ts-ignore
Token.abi,
// #ts-ignore
Token.networks[networkId].address
);
}
}
I also was told that I should simply add a .catch() to web3.eth.net.getId() but this did nothing. Am I doing something wrong or is this a dependency problem? If anyone could point me in the right direction I would really appreciate it. Do I need to expose the util API to the browser somehow? To me, it seems that the API is simply not available.
This is should be the relevant part of my vite.config.ts:
import GlobalsPolyfills from '#esbuild-plugins/node-globals-polyfill';
import NodeModulesPolyfills from '#esbuild-plugins/node-modules-polyfill';
import { defineConfig } from 'vite';
import react from '#vitejs/plugin-react';
export default defineConfig({
plugins: [
react(),
],
optimizeDeps: {
esbuildOptions: {
plugins: [
NodeModulesPolyfills(),
GlobalsPolyfills({
process: true,
buffer: true,
}),
],
define: {
global: 'globalThis',
},
},
},
});
Here is my complete vite config
https://pastebin.com/zvgbNbhQ
Update
By now I think that I understand the issue - it seems that it is a VIte-specific problem and I need to polyfill the NodeJs.util API. I am already doing this (at least I thought). Perhaps someone can provide some guidance on what I am doing wrong with my config?
Update 2
I actually have now the util API inside the browser, but it is still giving me the same error. This is my new config:
https://pastebin.com/mreVbzUW I can even log it out:
Update 3
SO I am still facing this issue - I tried a different approach to polyfill I posted the update to the github issue https://github.com/ChainSafe/web3.js/issues/4992#issuecomment-1117894830
Had similar problem with vue3 + vite + we3
It's started from errors: process in not defined than Buffer is not defined and finally after I configure polyfill I came to callbackify is not defined
Did a lot of researches and finally solved this issue with next trick:
Rollback all polyfill configurations
Add to the head html file
<script>window.global = window;</script>
<script type="module">
import process from "process";
import { Buffer } from "buffer";
import EventEmitter from "events";
window.Buffer = Buffer;
window.process = process;
window.EventEmitter = EventEmitter;
</script>
vite.config.ts
import vue from '#vitejs/plugin-vue'
export default {
resolve: {
alias: {
process: "process/browser",
stream: "stream-browserify",
zlib: "browserify-zlib",
util: 'util'
}
},
plugins: [
vue(),
]
}
add these dependencies browserify-zlib, events, process, stream-browserify, util
Source https://github.com/vitejs/vite/issues/3817#issuecomment-864450199
Hope it will helps you

Problem with parsing javascript file marked as Shebang

I have a react app where I wanted to import a javascript file from a third-party library but file is mark with shebang #!/usr/bin/env node.
I found (e.g. here How to Configure Webpack with Shebang Loader to Ignore Hashbang Importing Cesium React Component into Typescript React Component) I can load file by overriding webpack configuration and adding a new loader shebang-loader (I also have tried shebang-loader2) but overriding webpack in react app is recommended only with #craco/craco so I added it to package.json and tried add loader to existing webpack-config.js.
I produced this lines of code. File craco.config.js:
const throwError = (message) =>
throwUnexpectedConfigError({
packageName: 'craco',
githubRepo: 'gsoft-inc/craco',
message,
githubIssueQuery: 'webpack',
});
module.exports = {
webpack: {
configure: (webpackConfig, {paths}) => {
const shebangLoader = { test: /node_modules\/npm-groovy-lint\/lib\/groovy-lint.js$/, loader: "shebang-loader" }
const {isAdded: shebangLoaderIsAdded1} = addAfterLoader(webpackConfig, loaderByName('url-loader'), shebangLoader);
if (!shebangLoaderIsAdded1) throwError('failed to add shebang-loader');
return webpackConfig;
},
},
};
It resolves problem with shebang and it ignores #!/usr/bin/env node but now I still get error
Module parse failed: Unexpected token (14:16)
File was processed with these loaders:
* ./node_modules/shebang2-loader/index.js
You may need an additional loader to handle the result of these loaders.
| const { getSourceLines, isErrorInLogLevelScope } = require("./utils");
| class NpmGroovyLint {
> "use strict";
| options = {}; // NpmGroovyLint options
| args = []; // Command line arguments
It looks like it does not recognise "use strict" line.
Can anyone put some suggestions what should be a problem ?
After few hours of investigation, I have finally come to a resolution. Firstly I have to say that there is no option to use NpmGroovyLint in react-like applications that run in browsers because after I resolved mentioned problem up here I figured that NpmGroovyLint uses node libraries as perf_hooks which are not available in a browser enviroment.
But I can post code that resolves the problem described in my question. It was needed to add a plugin to babel-loader named 'plugin-proposal-class-properties'. Here is my snipped of craco config. You can use it as a recipe occasionally.
const {addAfterLoader, getLoaders, loaderByName, removeLoaders, throwUnexpectedConfigError} = require('#craco/craco');
const throwError = (message) =>
throwUnexpectedConfigError({
packageName: 'craco',
githubRepo: 'gsoft-inc/craco',
message,
githubIssueQuery: 'webpack',
});
module.exports = {
webpack: {
configure: (webpackConfig, {paths}) => {
const {hasFoundAny, matches} = getLoaders(webpackConfig, loaderByName('babel-loader'));
if (!hasFoundAny) throwError('failed to find babel-loader');
const {hasRemovedAny, removedCount} = removeLoaders(webpackConfig, loaderByName('babel-loader'));
if (!hasRemovedAny) throwError('no babel-loader to remove');
if (removedCount !== 2) throwError('had expected to remove 2 babel loader instances');
//add plugin proposal class properties to existing babel loader
const propClassOptions = {...matches[1].loader.options, ...{plugins: ["#babel/plugin-proposal-class-properties"]}};
const propClassLoader = {...matches[1].loader, ...{options: propClassOptions}};
const babelLoaderWithPropClassPlugin = {...matches[1], ...{loader: propClassLoader}};
const shebangLoader = {
test: /node_modules\/npm-groovy-lint\/lib\/groovy-lint.js$/,
use: [{loader: 'shebang2-loader'}, {...{loader: require.resolve('babel-loader')}, ...{options: propClassOptions}}]
}
const {isAdded: babelLoaderWithPropClassIsAdded} = addAfterLoader(webpackConfig, loaderByName('url-loader'), matches[0].loader);
if (!babelLoaderWithPropClassIsAdded) throwError('failed to add ts-loader');
const {isAdded: babelLoaderIsAdded} = addAfterLoader(webpackConfig, loaderByName('babel-loader'), babelLoaderWithPropClassPlugin.loader);
if (!babelLoaderIsAdded) throwError('failed to add back babel-loader for non-application JS');
const {isAdded: shebangLoaderIsAdded1} = addAfterLoader(webpackConfig, loaderByName('url-loader'), shebangLoader);
if (!shebangLoaderIsAdded1) throwError('failed to add shebang-loader');
return webpackConfig;
},
},
};

nuxtjs/router use runtime config client side

we are using nuxt 2.14.12 and #nuxtjs/router 1.5.0
we are trying to use runtime config to make some HTTP request client side.
here is our router.js
export async function createRouter(ssrContext, createDefaultRouter) {
[...]
try {
const res = await axios.get(`${config.public.apiBaseUrl}/myslug`)
} catch (e) { }
[...]
}
here is the config file
[...]
const apiBaseUrl = `${process.env.NUXT_ENV_MY_API_URL || 'http://my-dev-domain.com'}`
[...]
export default {
apiBaseUrl,
},
private: {
apiBaseUrl,
},
[...]
here is our nuxt.config.js
export default {
[...]
publicRuntimeConfig: config.public,
privateRuntimeConfig: config.private,
[...]
buildModules: [
['#nuxtjs/router', { keepDefaultRouter: true }],
],
[...]
router: {
linkActiveClass: 'current-menu-item'
},
[...]
}
we use nuxt build in our CI and later at runtime we use nuxt start
at runtime, despite on server side the env variable NUXT_ENV_MY_API_URL is correctly set, on the client site the variable looks hardcoded (I think webpack replace it) and we get the value present on build time (http://my-dev-domain.com)
is there a way to use the runtime config on the client side?
thank you

Importing custom CommonJS module fails

I created a CommonJS module in project A in the following way:
const { WebElement } = require('selenium-webdriver');
const { By } = require('selenium-webdriver');
class VlElement extends WebElement {
constructor(driver, selector) {
...
}
async getClassList() {
...
}
}
module.exports = VlElement;
In project B I use the following code:
const VlElement = require('projectA');
class VlButton extends VlElement {
constructor(driver, selector) {
super(driver, selector);
}
...
}
module.exports = VlButton;
When running the code, VLElemlent cannot be found.
It is in my package.json and I can see VLElement under projectB > node_modules > projectA.
What am I doing wrong with my exports?
Thanks in advance.
Regards
Make sure you have a projectB/mode_modules/package.json with a main which points to the file that defines/exports VlElement, like this:
"main": "path/to/file/with/VlElement.js",
When you call require('projectA'); this has to be resolved to a file inside projectA so that it can be evaluated to (and return) the exports from that file. The main entry in the package.json allows this (but defaults to index.js, so if you are using that you don't need package.json, probably, but you should have it anyway).
You can have multiple files with various exports, but remember require('projectA'); can still only return one thing, so the way to do that is usually to have an index.js which looks something like:
module.exports = {
'something': require('./something.js'),
'otherthing': require('./otherthing.js'),
'etc': require('./etc.js'),
};

Is it possible to use Jest with multiple presets at the same time?

Is it possible to use Jest with multiple presets, say jsdom and react-native?
I'd like to test a React component that can work both on Web and in a React Native environment. The problem is that the component may use either React Native libraries or some document's methods.
When I run some tests, jest replies:
Cannot find module 'NetInfo' from 'react-native-implementation.js'
When I try to add
"jest": {
"preset": "react-native"
}
to package.json, I get:
ReferenceError: window is not defined
Presets are just plain Javascript objects, so in many circumstances you may simply merge them. For example, that's how I'm enabling ts-jest and jest-puppeteer simultaneously:
const merge = require('merge')
const ts_preset = require('ts-jest/jest-preset')
const puppeteer_preset = require('jest-puppeteer/jest-preset')
module.exports = merge.recursive(ts_preset, puppeteer_preset, {
globals: {
test_url: `http://${process.env.HOST || '127.0.0.1'}:${process.env.PORT || 3000}`,
},
})
If there are certain options that can't be 'merged' like that, just handle these cases manually.
Along these same lines, you can do this with the spread operator:
const tsPreset = require('ts-jest/jest-preset')
const puppeteerPreset = require('jest-puppeteer/jest-preset')
module.exports = {
...tsPreset,
...puppeteerPreset,
globals: {
test_url: `http://${process.env.HOST||'127.0.0.1'}:${process.env.PORT||3000}`,
},
}
For people that are looking for one preset plus typeScript
const { defaults: tsjPreset } = require('ts-jest/presets')
module.exports = merge.recursive(ts_preset, puppeteer_preset, {
preset: 'Your_Preset',
transform: tsjPreset.transform,
},
})

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