Crate config

More Configuration  

More Configuration is a configuration library for Rust.

You may be looking for:

• User Guide
• API Documentation
• Release Notes

Features

This crate provides the following features:

• default - Abstractions for configuration, including the std features
• std - Standard configuration implementation
• 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

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)]
struct Client {
    region: String,
    url: String,
}

#[derive(Default, Deserialize)]
struct AppOptions {
    text: String,
    demo: bool,
    clients: Vec<Client>,
}

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

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

License

This project is licensed under the MIT license.

Re-exports

• pub use 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.