Struct confik::ConfigBuilder

pub struct ConfigBuilder<'a, Target: Configuration> { /* private fields */ }

Used to accumulate ordered sources from which its Target is to be built.

An instance of this can be created via Configuration::builder or ConfigBuilder::<T>::default.

Examples

Using Configuration::builder:

use confik::{Configuration, TomlSource};

#[derive(Debug, PartialEq, Configuration)]
struct MyConfigType {
    param: String,
}

let config = MyConfigType::builder()
    .override_with(TomlSource::new(r#"param = "Hello World""#))
    .try_build()
    .expect("Failed to build");

assert_eq!(config.param, "Hello World");

Using ConfigBuilder::<T>::default:

use confik::{ConfigBuilder, Configuration, TomlSource};

#[derive(Debug, PartialEq, Configuration)]
struct MyConfigType {
    param: String,
}

let config = ConfigBuilder::<MyConfigType>::default()
    .override_with(TomlSource::new(r#"param = "Hello World""#))
    .try_build()
    .expect("Failed to build");

assert_eq!(config.param, "Hello World");

Implementations

impl<'a, Target: Configuration> ConfigBuilder<'a, Target>

pub fn override_with(&mut self, source: impl Source + 'a) -> &mut Self

Add a single Source to the list of sources.

The source is added at the end of the list, overriding existing sources.

use confik::{Configuration, TomlSource};
#[derive(Debug, PartialEq, Configuration)]
struct MyConfigType {
    param: String,
}

let config = MyConfigType::builder()
    .override_with(TomlSource::new(r#"param = "Hello World""#))
    .override_with(TomlSource::new(r#"param = "Hello Universe""#))
    .try_build()
    .expect("Failed to build");

assert_eq!(config.param, "Hello Universe");

pub fn try_build(&mut self) -> Result<Target, Error>

Attempt to build from the provided sources.

Examples found in repository

examples/defaulting.rs (line 26)

fn main() {
    let config = Config::builder()
        .try_build()
        .expect("Failed to parse config");

    assert_eq!(
        config,
        Config {
            field1: 5,
            field2: String::from("Hello World"),
            data: Data {
                elements: vec![4, 3, 2, 1],
            },
        }
    );
}

Trait Implementations

impl<'a, Target: Configuration> Default for ConfigBuilder<'a, Target>

fn default() -> Self

Returns the “default value” for a type.