Reading single line from file

[wildwestrom]

Is it possible to do this with figment?
If so, where should I be looking?

[SergioBenitez]

Can you be more specific about what you want to do? An example would be great.

[wildwestrom]

Something like this.

fn build_cli() -> Result<Cli> {
	let mut cli = Figment::new().merge(Serialized::defaults(Cli::parse()));
	if let Some(path) = CONFIG_FILE_PATH.as_ref() {
		cli = cli.merge(Data::<MyOwnProviderType>::file(path.as_path()));
	}
	Ok(cli.extract()?)
}

So what if I want a custom figment::providers::Data?

The file I would be looking at might look something like this:

65535

Or this:

long-option = 465
another-long-option = "Hello"

[SergioBenitez]

It's not clear from your example which line should be read, what should happen if the file is empty, and how the line should be parsed. But in any case, yes it would be straightforward to implement such a provider. Alternatively, you can simply read the line from the file using the lines() I/O reader and pass the string to any existing provider.

[SergioBenitez]

I see you've added to your previous comment. It sounds like you want a custom provider, since your file doesn't seem to have any obvious relation to existing formats. It's not clear what the file should be parsed as, or which line you want to keep and what that line means.

The figment docs are complete. See Format for what you probably need.

[wildwestrom]

Yeah, I haven't figured out any specifics in terms of how things will be parsed. I just wanted to find out how to extend it. Thank you.