Electron creating various folders and files in my directory

Question

I am developing an application with Electron where I need to store some important data in a directory that I created in %APPDATA%.

The problem is that whenever I create this folder (I create using fs.mkdirSync), several files and folders are created within it at once. See the files that are created below:

AppData/Roaming/myFolder/  <---¬
    myOtherFolder/         <---l-----[Essas duas pastas são as únicas que eu crio]
    blob_storage/
    Cache/
    Code Cache/
    Dictionaries/
    FontLookupTableCache/
    GPUCache/
    Local Storage/
    Session Storage/
    Network Persistent State
    Preferences

What are these folders and files created? How can I prevent this so that it gets only the two folders I created?

Answer 1

The Electron, as I said before in a commenting, is based on Chromium, as well as Chrome, Opera, Bravo, etc.

So the application created in HTML+CSS+JS is actually a hybrid application, IE, your program is a browser "disguised as a normal program", these folders are all used by the technologies you have in engines of Chromium, see Devtools:

To change the location you need to use app.setPath(name, path) using the value of name as userData:

 app.setPath('userData', '/pasta/foo/bar');

Being /pasta/foo/bar the new location of these folders, of course it is an example. However I must make it clear that the best place to keep temporary files is in the user folder, so I see no reason to change, what you can do if you really want to change (which I insist seems dispensable) is to take the value of userData with app.getPath('userData') and apply as sub-folder:

const userData = app.setPath('userData', '/pasta/foo/bar');

app.setPath('userData', `${userData}/chromium`);

I haven’t tested, but I may have to create the folder manually, so if it doesn’t work:

var fs = require('fs');

const userData = app.setPath('userData', '/pasta/foo/bar');

try {
    fs.mkdirSync(`${userData}/chromium`);
} catch (ee) {
    if (ee.code !== 'EEXIST') {
        throw e; //Se o erro não for sobre existir então irá emitir um erro e seu programa não irá iniciar
    }
}

app.setPath('userData', `${userData}/chromium`);

---

Note: You can even erase, but the engines will generate again and you can be sure that there are folders that haven’t appeared yet because your application hasn’t used things like:

• https://developer.mozilla.org/en-US/docs/Web/API/FileSystem which will probably generate the folder File System (I’m not sure, Chromium documentation is very complicated)
• Or if you use videos you might generate the folder VideoDecodeStats

I did not find details of all folders, but here goes almost everything:

• blob_storage probably to control the blobs generated as with the use of the API Blob or URL.createObjectURL

• Cache contain HTTP request caching (it depends on how you configure your project)

• Code Cache this I do not know how it works for sure, but it seems that are caches of structures JS and wasm specific of some sites, not found sources

• Dictionaries dictionaries for spell checker

• FontLookupTableCache - I’ll edit it soon, it looks like it’s

• GPUCache cache used by the program for GPU use

• Local Storage for use of the API localStorage

• Session Storage for use of the sessionStorage API

• Network Persistent State probably to keep the persistence settings for HTTP requests

• Preferences all preferences configured from browser/program

Summing up is only for control of own embedded browser, you yourself will not use them fully, will only use "indirectly"