npm package uses fs in wrong dir - node.js

Question

I have made a very simple npm package to support my discord bot.
In my bot code, I am trying to use a function from my package. However, when I launch bot code, I receive this error:
Error: ENOENT: no such file or directory, open 'prefixes.json'
I have a prefixes.json file in the main dir of npm package. In the package this code (which returns an error) is executed:
const contents = fs.readFileSync(`prefixes.json`);
const jsonPrefixes = JSON.parse(contents);
This code is executed when I turn on my discord bot that is dependant on this package. prefix.json is in the same dir as index.js of my npm package. I tried ./prefix.json and prefix.json, none of which worked.
Is the error because the package tries to search in my bot dir, instead of his own? How do I overcome this?
Update: When I tried ./node_modules/kifo/prefixes.json it worked, but I don't want it like that - is there a way to provide a path relative to the package?

Answer 1

You need to use require() instead of fs.readFileSync():
const jsonPrefixes = require('./prefixes.json');
const contents = JSON.stringify(jsonPrefixes); // you don't actually need this
Why?
The reason why fs.readFileSync() must behave the way it does is because file API in all programming languages behave that way. Say for example you write a program called dump. The working directory must be the one the user is currently in otherwise if you do:
> cd /my/folder
> ls
test.txt
> dump test.txt
Error: cannot open /path/to/node_modules/dump/test.txt
Of course YOU DO NOT EXPECT THIS. Nor should you. You should not expect fs.readFileSync to use it's own module directory to open files from.
On the other hand, require() was designed to load javascript modules, some of which are form your own project. So require() will open files from the directory the code is in.
The require() function can load either javascript code or a JSON file. So in your case you can use require().
What if it's not JSON?
If you cannot use require() you can use the __dirname variable. It is a special variable that contains the path of the currently executing module:
const contents = fs.readFileSync(`${__dirname}/prefixes.json`);
const jsonPrefixes = JSON.parse(contents);
However for JSON I still prefer to use require().