RosettaCodeData/Task/Read-a-configuration-file/Rust/read-a-configuration-file.rs

81 lines
2.6 KiB
Rust

use std::fs::File;
use std::io::BufRead;
use std::io::BufReader;
use std::iter::FromIterator;
use std::path::Path;
fn main() {
let path = String::from("file.conf");
let cfg = config_from_file(path);
println!("{:?}", cfg);
}
fn config_from_file(path: String) -> Config {
let path = Path::new(&path);
let file = File::open(path).expect("File not found or cannot be opened");
let content = BufReader::new(&file);
let mut cfg = Config::new();
for line in content.lines() {
let line = line.expect("Could not read the line");
// Remove whitespaces at the beginning and end
let line = line.trim();
// Ignore comments and empty lines
if line.starts_with("#") || line.starts_with(";") || line.is_empty() {
continue;
}
// Split line into parameter name and rest tokens
let tokens = Vec::from_iter(line.split_whitespace());
let name = tokens.first().unwrap();
let tokens = tokens.get(1..).unwrap();
// Remove the equal signs
let tokens = tokens.iter().filter(|t| !t.starts_with("="));
// Remove comment after the parameters
let tokens = tokens.take_while(|t| !t.starts_with("#") && !t.starts_with(";"));
// Concat back the parameters into one string to split for separated parameters
let mut parameters = String::new();
tokens.for_each(|t| { parameters.push_str(t); parameters.push(' '); });
// Splits the parameters and trims
let parameters = parameters.split(',').map(|s| s.trim());
// Converts them from Vec<&str> into Vec<String>
let parameters: Vec<String> = parameters.map(|s| s.to_string()).collect();
// Setting the config parameters
match name.to_lowercase().as_str() {
"fullname" => cfg.full_name = parameters.get(0).cloned(),
"favouritefruit" => cfg.favourite_fruit = parameters.get(0).cloned(),
"needspeeling" => cfg.needs_peeling = true,
"seedsremoved" => cfg.seeds_removed = true,
"otherfamily" => cfg.other_family = Some(parameters),
_ => (),
}
}
cfg
}
#[derive(Clone, Debug)]
struct Config {
full_name: Option<String>,
favourite_fruit: Option<String>,
needs_peeling: bool,
seeds_removed: bool,
other_family: Option<Vec<String>>,
}
impl Config {
fn new() -> Config {
Config {
full_name: None,
favourite_fruit: None,
needs_peeling: false,
seeds_removed: false,
other_family: None,
}
}
}