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§More Configuration

More Configuration is a configuration library for Rust.

You may be looking for:

§Features

This crate provides the following features:

default - Abstractions for configuration, including the std features
std - Standard configuration implementation
all - Includes all features, except async
async - Use configuration in an asynchronous context
mem - An in-memory configuration source
env - An environment variables configuration source
cmd - A command-line argument configuration source
json - A *.json file configuration source
xml - A *.xml file configuration source
ini - An *.ini file configuration source
chained - Chain multiple configuration sources
binder - Bind a configuration to strongly-typed values and structs

Use --features all,async for all features with asynchronous support

§Configuration in Action

Consider the following demo.json file:

{
  "text": "Hello world!",
  "demo": true,
  "clients": [{
    "region": "us-west",
    "url": "https://tempuri.org"
  }]
}

The configuration can be loaded, merged, and accessed from multiple sources:

use config::{*, ext::*};

fn main() {
    let config = DefaultConfigurationBuilder::new()
        .add_in_memory(&[("Demo", "false")])
        .add_json_file("demo.json".is().optional())
        .add_env_vars()
        .add_command_line()
        .build()
        .unwrap();
    
    if let Some(demo) = config.get("demo") {
      if demo.as_str() == "true" {
        println!("{}", config.get("Text").unwrap().as_str());
        println!("{}", config.get("Clients:0:Region").unwrap().as_str());
        return;
      }
    }
    
    println!("Not a demo!");
}

Raw configuration values can be used, but they are much more interesting when we data bind them to strongly-typed values:

use serde::Deserialize;

#[derive(Default, Deserialize)]
#[serde(rename_all(deserialize = "PascalCase"))]
struct Client {
    region: String,
    url: String,
}

#[derive(Default, Deserialize)]
#[serde(rename_all(deserialize = "PascalCase"))]
struct AppOptions {
    text: String,
    demo: bool,
    clients: Vec<Client>,
}

The first letter of JSON configuration keys are normalized to uppercase.

use config::{*, ext::*};

fn main() {
    let file = std::env::current_exe()
        .unwrap()
        .parent()
        .unwrap()
        .join("../../demo.json");
    let config = DefaultConfigurationBuilder::new()
        .add_json_file(file)
        .build()
        .unwrap();
    let app: AppOptions = config.reify();
    
    if app.demo {
        println!("{}", &app.text);
        println!("{}", &app.clients[0].region);
        return;
    }
    
    println!("Not a demo!");
}

§Minimum Supported Rust Version

When increasing the minimum supported Rust version (MSRV), the new version must have been released at least six months ago. The current MSRV is 1.60.

§License

This project is licensed under the MIT license.

Re-exports§

pub use util::*;util

Modules§

ext: Contains configuration extension methods.
util: Contains configuration utility functions.

Structs§

ChainedConfigurationProviderchained: Represents a chained ConfigurationProvider.
ChainedConfigurationSourcechained: Represents a chained ConfigurationSource.
CommandLineConfigurationProvidercmd: Represents a ConfigurationProvider that provides command line configuration values.
CommandLineConfigurationSourcecmd: Represents a ConfigurationSource for command line data.
ConfigurationIterator: Represents an iterator of key/value pairs for a Configuration.
DefaultConfigurationBuilderstd: Represents a configuration builder.
DefaultConfigurationRootstd: Represents the root of a configuration.
DefaultConfigurationSectionstd: Represent a configuration section.
EnvironmentVariablesConfigurationProviderenv: Represents a ConfigurationProvider for environment variables.
EnvironmentVariablesConfigurationSourceenv: Represents a ConfigurationSource for environment variables.
FileSource: Represents a file configuration source.
FileSourceBuilder: Represents a builder for a file source.
IniConfigurationProviderini: Represents a ConfigurationProvider for *.ini files.
IniConfigurationSourceini: Represents a ConfigurationSource for *.ini files.
JsonConfigurationProviderjson: Represents a ConfigurationProvider for *.json files.
JsonConfigurationSourcejson: Represents a ConfigurationSource for *.json files.
MemoryConfigurationProvidermem: Represents a ConfigurationProvider that provides in-memory configuration values.
MemoryConfigurationSourcemem: Represents a ConfigurationSource for in-memory data.
XmlConfigurationProviderxml: Represents a ConfigurationProvider for *.xml files.
XmlConfigurationSourcexml: Represents a ConfigurationSource for *.xml files.

Enums§

ConfigurationPath: Represents a configuration path.
LoadError: Defines the possible load errors.
ReloadError: Defines the possible reload errors.

Traits§

Configuration: Defines the behavior of a configuration.
ConfigurationBuilder: Defines the behavior used to build an application Configuration.
ConfigurationProvider: Defines the behavior of an object that provides configuration key/values for an application.
ConfigurationProviderIterator: Defines the behavior of an iterator over a ConfigurationProvider set.
ConfigurationRoot: Represents the root of a Configuration hierarchy.
ConfigurationSection: Defines the behavior for a section of application configuration values.
ConfigurationSource: Represents a source of configuration key/value pairs for an application.

Type Aliases§

LoadResult: Represents a configuration load result.
ReloadResult: Represents a configuration reload result.
Value: Represents the type alias for a configuration value.

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