Introducing not found error for config values

[AuHau]

No description provided.

[AuHau]

I have now realized that earlier I created issue #197 that propose the usage of interface-datastore.errors.notFound instead of this custom error.

@jacobheun what is your take on this?

[jacobheun]

@AuHau they should probably be separate. While they both have the same error code at the moment, the missing config key is not a database error. There's no guarantee the database code won't change in the future, so keeping them separate feels like a safer way to avoid issues down the road.

The err-code module is already being used in other places in ipfs-repo, is there any particular reason you're using error classes instead? If not it would probably be good to use the former.

[AuHau]

@jacobheun sounds good!

Well, it is a style of errors proposed in ipfs/js-ipfs#1746 that I silently highly prefer 😅 and I hope is the future in js-ipfs land. Should I refactor it nevertheless?

[jacobheun]

My only real hesitation with including them is that we have 2 ways errors are being created now. I know there is another PR open that adds another code. Would you be up for submitting another PR to replace the rest of the err-code usage?

[AuHau]

Sure! I will happily do that. It should not be even breaking change as the code properties will stay the same. I will make it happen tomorrow.