Background
I've been following more or less the official guide to setup a local dev environment with react and it seems to use create-react-app, which sets up really a lot.
Now, if I run npm run build I get a minified version of everything in the build folder.
If I, however, run npm start the version NodeJS serves does not seem to have any modifications. But I cannot see these files.
Question
So either:
Can I access the files generated by npm start somewhere? As these seem to be unmodified. (build is never modified there)
Or can I somehow run npm run build, so it does a "development" build with unminimized files?
Tries
My aim is just to get access to an unminimized version of react scripts.
As for the last question I've tried some parameters and enironmental variables as suggested in this question, but as you can see, it failed:
$ NODE_ENV=dev npm run build --dev --configuration=dev
> example-project#0.1.0 build [...]
> react-scripts build
Creating an optimized production build...
[...]
System
My package.json has the default scripts:
"scripts": {
"start": "react-scripts start",
"build": "react-scripts build",
"test": "react-scripts test",
"eject": "react-scripts eject"
},
Note: Please do not ask why I am doing it or try to convince me that it is bad. There are many reasons why I'd maybe want this, e.g. debugging or this specific use case.
To change the webpack config and build scripts you have either to eject from create-react-app (i would not recommend this step, as it breaks future compatibility) or use tools like rewire to override some settings
Take a look at this.
https://github.com/timarney/react-app-rewired
I personally used just rewire
npm i rewire --save-dev
Here is a sample config i created for one of my projects in the past and it worked pretty good!
Create build.js
Change your package.json so that it runs build.js
build.js
const rewire = require('rewire');
const defaults = rewire('react-scripts/scripts/build.js');
const config = defaults.__get__('config');
// Consolidate chunk files instead
config.optimization.splitChunks = {
cacheGroups: {
default: false,
},
};
// Move runtime into bundle instead of separate file
config.optimization.runtimeChunk = false;
// JS
config.output.filename = '[name].js';
// CSS. "5" is MiniCssPlugin
config.plugins[5].options.filename = '[name].css';
config.plugins[5].options.publicPath = '../';
Then in my package.json i changed the npm script links like this
(node build which will run the build.js script)
package.json
"scripts": {
"start": "react-scripts start",
"build": "node build && gulp",
"test": "react-scripts test",
"eject": "react-scripts eject"
},
So if you really want to eject from create-react-app, all you have to do is to run
npm run-script eject
Then you will get a new folder with all configs used by create-react-app
But as i said before, there is no reason why not to use rewire and just override the config instead of ejecting.
I wanted the unobfuscated code of a React app - mostly of curiosity, I had the source - while having the job of rewriting it in Angular (producing a far more maintainable app 5% of the size and 1% dependencies).
I've never used React but discovered by modifying the file
<base_path>/node_modules/react-scripts/config/webpack.config.prod.js
and replacing the large optimization config item, under module.exports, with the following...
module.exports = {...
optimization: {
minimize: false,
splitChunks: {
chunks: 'all',
name: true
},
runtimeChunk: true
},
npm run build built unobfuscated, readable code that ran as expected, using no other modifications. Used Gitbash only with the commands npm install, npm run build and npm start - Just thought someone may find that useful.
I don't recommend this because the code you want is still wrapped in a webpack eval mess. It's easier to pick the useful bits from the source or just rebuild the app. At best, I got to see what a cluster react and webpack is.
Why can't you see the source files? Here is what I would try:
Start your react app with npm run start
Open your browser to http://localhost:3000
Open Developer tools and inspect the created chunked bundles by the webpack-dev server. In Chrome on a mac, you can do the following: cmd+option+j will open developer tools. Then click the sources tab: within this tab you will see the bundles created by react's build configuration. Now the output of these bundles might not be pretty but it's all there.
Alternatively, all your application's build configuration settings are contained within your webpack.config.js file even when you use create-react-app. As this configuration is just encapsulated within the react-scripts node module. So maybe you could try editing this file directly, without ejecting: <base_path>/node_modules/react-scripts/config/webpack.config.js. Although you need to be careful as to not break an existing configuration setting. You probably want to mess with the source-map settings for production builds. At least this way if you ruin this file you can always just remove and reinstall react-scripts and be back to your initial configuration. This will also allow you to play around with your customizations in 'semi-safe' sandboxed environment. Remember, there is no magic that create-react-app is providing rather it's just making useful defaults for your build configuration.
Lastly, as #xzesstence pointed out you can try out the react-app-rewired module.
Hopefully that helps!
The files are kept in the server process memory and not written to disk, unless you eject the scripts (or if it is possible to use a tool like 'rewire') and modify them to write it to disk using the writeToDisk option as described in the webpack DevServer docs.
You can however get the actual file list/links by navigating to the webpack-dev-server endpoint under the server.
For instance if using the default url at localhost:3000 then use the following url to see all files on the server:
http://localhost:3000/webpack-dev-server
But what you really need is only the index.html (which is in general just a stub that loads the JS files) and the 3 following JS files which appear to be consistent on all create-react-app installments, along with their respective source map files.
main.chunk.js
bundle.js
vendors~main.chunk.js
You can just right click on the links on the page and save them, or you can navigate direct the link or get them from the Chrome Dev Tools "sources" tab.
Note that in general for code changes only the main.chunk.js file is updated, so for the average code change you might just fetch the updated main.chunk.js and main.chunk.js.map files.
I know it's way too late to answer this, but try this npm i -D cra-build-watch.
I feel this library is underrated but it just watch the changes in react app and does not re-build the whole package again and again.
Although rewiring helps in making the build by not minifying it, however, still it goes through the whole process of building again and again.
After spending a whole day on this problem, I could not find a way to get the none-minified version of the production code,
what I did was: open the dev tools on chrome, navigate to the sources tab; now find the javascript file (in create-react-app it is usually in static > js > main.js)
when the javascript file is visible, at the bottom left of the screen a pair of curly braces appear (look at the image):
screenshot of the dev tools
when you click on the curly braces, it beautifies the code, and then you can add breakpoints to the code (click on the number on the line ) and refresh the page to start the debugger, it is not convenient to deal with that code, but for now that is what worked for me.
hope it helps.
I'm using visual studio code on Windows 10, with jasmine and nodemon
How does one set up their package.json such that you can run jasmine continuously, yet also be able to drop breakpoints in visual studio code to debug? I feel like I've been searching for ages on how to do some kind of setup like this.
Here is what I currently have in package.json. Running this allows me to write in my .spec files and jasmine gets continualy run on each change:
"scripts": {
"test": ".\\node_modules\\.bin\\nodemon --inspect --ext js --exec \".\\node_modules\\.bin\\jasmine\""
},
Anyone have a magical command to allow debugging any spec file, or any file which the tests execute against?
I'm writing an app that is composed of microservices (I use micro).
I really like es6, so I use Babel to make the development process easier. The problem that I have is that I need a script that would compile my es6 code and restarted the 'server'; I don't know how to achieve this.
Right now I have the following script in my package.json:
"scripts": {
"start": "yarn run build && micro",
"build": "./node_modules/.bin/babel src --out-dir lib"
},
When I run yarn start my es6 code compiles successfully and micro starts the server. However, if I make changes to my code, I'll have to manually stop the server and run yarn start again.
I've tried to change my build script
"build": "./node_modules/.bin/babel src --watch --out-dir lib"
But in this case the micro command does not get executed as the build script just watches for changes and blocks anything else from execution. My goal is to have a script that would watch for changes and restart the server if a change occurred (compiling the code beforehand) like in Meteor.
One option is using ParallelShell module to run shell commands in parallel. You can find an example of how to use it here
The simplest solution would be to yarn run build & micro (note the single & and not &&).
As mentioned by others, parallelshell is another good hack (probably more robust than &).
Currently, I have two folders: __tests__ for unit (fast) tests and __integration__ for slow tests.
Then, in package.json:
{
"scripts": {
"test": "jest",
"test:integration": "jest -c '{}'",
...
},
"jest": {
"testPathIgnorePatterns": ["/node_modules/", "__integration__"]
}
}
So, when I want to do TDD, I'm running just npm test and when I want to test the entire project, npm run test:integration.
As Jest is offered as a "no configuration" test framework, I was thinking if there's a better (or proper) way to configure this.
Thank you.
Quoting from this post.
You can try name files like:
index.unit.test.js and api.int.test.js
And with Jest’s pattern matching feature, it makes it simple to run
them separately as well. For unit testing run jest unit and for
integration testing run jest int.
File structure/location you can define based on your preferences as the pattern matching based on the file name is how jest knows what to run.
Also see jest cli documentation about npm scripts:
If you run Jest via npm test, you can still use the command line
arguments by inserting a -- between npm test and the Jest arguments
Have you tried jest --watch for TDD? It runs only files related to your git changes, runs errors first and heavily utilise cache for speed.
Other than that, jest -c accepts a path, not a string. You should be good with jest -c jest-integration-config.json, provided that jest-integration-config.json sits in your project's root.
On using WebStorm 10 for Node.js dev, I am unable to step through the test cases (written in ES6) while debugging. I guess the transcompilation is making the test file go out of sync. Wondering if anyone has been able to debug successfully?
Here is my test.js file
describe('TestFlow', function () {
"use strict";
it('Test Path', (done) => {
console.log("Testing_1 happy path\n");
console.log("Testing_2 happy path\n");
done();
});
});
And I have the Mocha options configured to use --compilers js:babel/register. Now when I try to debug the code, the step through process is unpredictable and it just doesn't work. The babel compilation is messing with the debugging process.
Could you please let me know if there is a work around to this issue? I thought the debugging ES6 code was a feature in WebStrom 10, but I have not had luck with it
This works now in at least WebStorm 2017.1. JetBrains has marked this issue as fixed
From terminal:
> npm install --save-dev babel-core babel-preset-es2015
Under the menu Run/Edit Configurations...Mocha Run/Debug configuration, enter this option:
Extra Mocha options: --compilers js:babel-core/register
Also, have a .babelrc file (or put in package.json)
{
"presets": [
"es2015"
]
}
You should now be able to run and debug your ES6 unit tests
See this article as well
Webstorm debugger won't work with runtime babel compilation. You need to first compile your ES6 files using babel with sourcemaps and place them let's say in dist directory. You can use this gulp task to do so.
In webstorm's debug mocha configuration point working directory to the above created dist directory. Also point test directory to your tests in dist directory. Put a breakpoint in the original ES6 test file and start your debug session.
In WebStorm go to Run/Edit Configurations.../Templates/Mocha/Extra Mocha options and insert the following (depends on version of babel: https://git.io/vdcSr).
Babel 7
--require #babel/register
Babel 6
--require babel-core/register