Visual Studio Code JSON completion - json

Question

I'm making my first videogame in Unity and I was messing around with storing data in JSON files. More specifically, language localization files. Each file stores key-value pairs of strings. Keys are grouped in categories (like "menu.pause.quit").
Now, since each language file is essentially going to have the same keys (but different values), it would be nice if VS code recognized and helped me write these keys with tooltips.
For example, if you open settings.json in VS code, if you try to write something, there's some kind of autocompletion going on:
How does that work?

Answer 1

The auto completion for json files is done with json schemas. It is described in the documentation:
https://code.visualstudio.com/docs/languages/json#_json-schemas-and-settings
Basically you need to create a json schema which describes your json file and you can map it to json files via your user or workspace settings:
// settings.json
{
// ... other settings
"json.schemas": [
{
"fileMatch": [
"/language-file.json"
],
"url": "./language-file-schema.json"
}
]
}
This will provide auto completion for language-file.json (or any other file matched by the pattern) based on language-file-schema.json(in your workspace folder, but you can also use absolute paths)
The elements of fileMatch may be patterns which will match against multiple files.