Dear developers,
Please don't use JSON for configuration files. It is intended for carrying data, and nothing else. Therefore, it is good at carrying data, and nothing else.
I strongly believe that anything that doesn't support comments shouldn't be used for configs. Comments are indispensable for short documentation, or putting a URL to proper documentation.
There are other plain text file formats better fit for this purpose, such as TOML, YAML, and even XML.
If you coded your program in JS, I understand that you might be inclined to use JSON. Maybe you want to reduce bloat or dependency by not including a TOML or YAML parser. But you are making it more difficult for us to contribute to your project, or fix something on our end.
It is quiet old too. Probably older than time itself given that it doesn't support date standards ISO 8601 or RFC 3339 out-of-the-box. That is because it doesn't need to, because it is not for configurations or manifests.
After reading so many replies, it is clear that way too many new variants of JSON were developed to make JSON do what it was never meant to do. JSON is for carrying data between server and client in JavaScript fashion. It is amazing for that purpose. After all, JS developers came to expect variable type errors to surface, and not worry about them.
This was already achieved with XML, but some people love to reinvent the tire, hence the JSON forks with comments i guess.
TOML would be horrible as a JS oriented data carrier.
TOML was meant to be a different thing, such as a well understood config format that is easily interpreted by both humans and machines. Semantics help avoid ambiguation. It ain't perfect.Lack of type declaration may get us sometimes. For instance, if people forget that phone and version "numbers" are actually strings, they may omit double qoutes causing them being interpreted as an integer, float or error.
But a comment line reminding us for such pitfall would go a long way.
Consider this:
distro_name = "Ubuntu"
distro_version = "14.10"
# Run this if you forgot your distro version: cat /etc/lsb-release | grep "RELEASE"
# Then enter version in double quotes.
TOML won't freak out like YAML if you have 8 of anything, or live in Norway. This doesn't mean that TOML is the most superior file format for configurations, XML is much better.
I asked what is your favourite file format for config files. In other words, which format you think should be the norm in IT industry.
Python. Fed to eval(). Sue me.
@murtezayesil of these three only TOML is intended to be a configuration language, but I would argue that *as a configuration language* Lua is better than TOML. That it also happens to be a programming language is a disadvantage for the use case of being a good configuration language, but I feel like its advantages outweigh that major disadvantage.
Second place is a bespoke config file format that looks like e.g. git-config or ssh's config language.
Third place is a sqlite3 file.
@murtezayesil
turtle (rdf). But i work very much with RDF graphs so getting information from and expressing information with them, you might have to get used to it.
So don't know if this is a better alternative for open source projects.
@murtezayesil I'd say that depends on several things.
The one thing I was assuming was that I need to write and maintain the config file as a human. For that, I find TOML quite easy to write and read.
If your config files are (auto-)generated and read only by software, it really doesn't matter at all as long as it follows one standard IMO.
> Window's central registry [...] It is an industry standard.
I'm not sure if this is standardized.
And: not every pattern is a sane way of doing things. Particularly when it comes from Microsoft. I can give you *lots* of examples where they did the most stupidest things where nobody is able to follow their reasoning. 🤷
@murtezayesil I subscribe to your message.
> My point is that we should use raise awareness for using standards for the purposes they were meant to serve.
However, this would also "prevent" or "suppress" creative ways of (re-)using technology which is also an important aspect.
So unless there is an issue related, I would not stick to "this is how it was meant to be" without a good reason.
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