Do not import "index.js" on folder import? - javascript

I am wondering if it is possible to re-configure the import behavior (looking for index.js) on importing module folders directly. By default, when you assume this module folder structure:
/components
/Button
/index.js
/style.scss
/Checkbox
/index.js
/style.scss
I can easily import the components like this:
import Button from 'components/Button';
import Checkbox from 'components/Checkbox';
But when I am working on that components, I will have multiple index.js files open in my editor/ide which will lead to confusion very quickly. Same applies for the style files.
What I did now is changing my folder structure to this:
/components
/Button
/Button.js
/Button.scss
/Checkbox
/Checkbox.js
/Checkbox.scss
Which solved that problem and I can see directly where each opened file belongs to.
However, now my component imports look a bit... verbose:
import Button from 'components/Button/Button';
import Checkbox from 'components/Checkbox/Checkbox';
Because obviously, webpack/babel would look for an "index.js" when I am importing a folder directly. Now my question is: can I change that behavior somehow? I'd like to tell webpack/babel that it should try to import a file named the same way as the folder as the index file.
You can re-configure directory indexes on every webserver, so I am hoping the same is possible with webpack/babel but googling didnt show anything up so far.

I went with the following solution:
In each of my folders, I will create a index.js next to the "real" module, that has the follwing content:
import module from './Button.js';
export default module;
This way I am able to keep my code in Button.js but am not required to import Button/Button someplace else.
I created a little script which automates the creation of the index.js files for me, so I don't have any additional work.

Related

Importing js modules by directory name

I'm upgrading a React application and have found that I need to modify the import statements to get them to work.
For example, in the old version, the following import works without errors:
import { User } from '../System'
Note that System is a directory on my file system that contains User, a js file that ends with export default User.
In my upgraded version of the app, the System directory still exists, but the above import gives me Can't resolve '../System' in 'C:\my app\.
It turns out that to get the import working properly now, I need to change it to the following:
import User from '../System/User';
If I understand correctly, this relates to js module system changes made with ES6.
My question, though, is regarding the specification of a directory in the import statement (System above). Why would it be that I was previously able to name a file directory in the import statement instead of the actual js script/module itself? Is that approach of using a directory in the import statement still possible? And if so, is it ever advisable?
Update: based on AKX's comment, I noticed the System directory does indeed contain an index.js, which apparently is what makes the import from the directory itself possible.
When an import points to a directory, and only a file, Webpack (which most React setups use) follows Node's's conventions and will attempt to import index.js from that directory if it exists. That's the only condition under which importing from a path that points to a directory works - your previous build probably had /System/index.js (which would allow importing with from '../System'). If you rename the file you're importing to anything else - such as to User.js - importing using only the directory path will fail.
And if so, is it ever advisable?
Sure, if you want. It's a style choice but is commonly done.

Import a single export seems to import the whole js file. How can I import just the exported object?

Exporting from one file index.js like this: export const categoriesObj = new Object(); and trying to import from another index.js file like this: import { categoriesObj } from "../app/index.js";, but I get an Uncaught ReferenceError: (variable from the other file) is not defined because instead of just importing the categoriesObj, I think is importing the whole file.
Currently I'm using webpack and babel. Both index.js files have separate bundle files. The folder structure looks like this:
dist
bundle1.js
bundle2.js
src
app
index.js
history
index.js
What I have tried is:
Add "type": "module" in package.json file.
Added babel-loader. Thought it was some problem with ES6 modules.
renamed ../app/index.js to index.mjs.
What I'm trying to do is to import an object which is generated in another file so I can use it on this other file.
Hope this makes sense. I've been stuck in this for days. Thanks for reading!

How to correctly use Webpack async imports

I'm trying to make a website with multiple components where each one is loaded with async import because I don't need every component (and maybe the user hasn't even access to it).
This is an example file structure (mine look somehow like that):
src/
utils/
...
index.ts
components/
home/
...
index.ts
about/
...
index.ts
contact/
...
index.ts
Now I import the needed component somewhere in src/index.ts (I'm using TypeScript). Everything is fine until here.
Now the problem: When I need to use files from utils in a component which is loaded with lazy-loading, is that file bundeled twice? So the first time with the main chunk and the second time with the component chunk? How can I tell Webpack that this file is already included and doesn't have to be bundeled again? So I want to use the same cached version again in a component that is lazy-loaded.

React project automatically export components by filename

I'm working on a fairly large project using react/webpack with a lot of components.
Currently my folder structure looks like this:
bin/
media/
src/
components/
login/
Login.js
LoginContainer.js
registration/
index.js
..
framework/
redux/
..
static/
test/
And in src/components/index.js I do the exports: export Login from ./Login/Login so that in other components I can just do import {Login, LoginContainer} from 'components' without having to search the file location.
Is there a way to not have the exports in the index.js like now?
I'd like to export automatically all javascript files by their name, without having to type it every time.
You can add (all of) your Components-SubFolders to your webpack.config.resolve and just import the Filename.
Or just add the components root to resolve.modulesDirectories and import the Path relative to the components-folder.

React JS Component based styling

I have this problem, I have these scss files for all my global variables:
colors.scss
fonts.scss
helpers.scss
And I have these scss files for my component based and import it on top of the .jsx files:
header.scss
footer.scss
searchbar.scss
My problem in all of my component based scss files, I need to import the color.scss and helpers.scss in that way it will be included multiple times in header.scss,footer.scss and searchbar.scss
How do you guys work on it, been searching for an hour and did not found any solutions.
Thanks!
Just make a app.scss file and import all the scss files into that one starting with your variable files.
We do a similar thing at my work and have one file that we import all our component scss files into and any shared dependencies go above those that way you are only having to import once. The main thing is to make sure that files with dependencies go below the dependency files.
Create a global scss like so:
global.scss => imports colors.scss, fonts.scss, helpers.scss
and include it in your root JS file.
This way, every time you create a module, it will have these default styles.

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