The irx-config library provides convenient way to represent/parse configuration from different sources. The main goals is to be very easy to use and to be extendable.

Features

• Fully compatible with serde
• Full deep merge of nested dictionaries/mappings
• Case sensitive/insensitive parameters names matching/merging
• Sealing secrets during display/debugging
• Get all configuration parameters or just cherry pick few
• Several embedded parsers available via library features:
  • Command-line argument (via clap)
  • Environment variables
  • File based parsers: JSON, YAML and TOML
• Could be extended with custom parsers

Examples

JSON with environment variables

To enable parsers used in example below, one has to add the following to Cargo.toml:

toml [dependencies] irx-config = { version = "1.0", features = ["env", "json"] }

```rust use irxconfig::parsers::{env, json}; use irxconfig::ConfigBuilder; use serde::Deserialize;

[derive(Deserialize)]

struct Conf { id: u32, logger: String, tag: String, }

// Data from two parsers will be merged. The values from parser appended first (JSON) // will take precedence if values have a same names let config = ConfigBuilder::default() .appendparser( json::ParserBuilder::default() .defaultpath("config.json") .build()?, ) .appendparser( env::ParserBuilder::default() .defaultprefix("APP_") .build()?, ) .load()?;

let conf_data: Conf = config.get()?; ```

Command-line, TOML and environment variables

To enable parsers used in example below, one has to add the following to Cargo.toml:

toml [dependencies] irx-config = { version = "1.0", features = ["cmd", "env", "toml-parser"] }

```rust use clap::App; use irxconfig::parsers::{cmd, env, toml}; use irxconfig::ConfigBuilder; use serde::Deserialize;

[derive(Deserialize)]

struct Logger { level: String, path: String, }

[derive(Deserialize)]

struct Connection { #[serde(default = "localhost")] host: String, port: u16, }

[derive(Deserialize)]

struct Conf { id: u32, logger: Logger, connection: Connection, }

let yaml = clap::loadyaml!("cmd.yaml"); let matches = App::fromyaml(yaml).get_matches();

// Data from three parsers will be merged. The values from parser appended first (cmd) // will take precedence if values have a same names let config = ConfigBuilder::default() .appendparser( cmd::ParserBuilder::default() .matches(matches) .tryargnamesfromyaml(includestr!("cmd.yaml"))? .build()?, ) .appendparser( toml::ParserBuilder::default() .defaultpath("config.toml") .pathoption("config") .build()?, ) .appendparser( env::ParserBuilder::default() .defaultprefix("APP") .prefix_option("prefix") .build()?, ) .load()?;

let conf_data: Conf = config.get()?; ```

Custom parser

```rust use irx_config::{AnyResult, Case, ConfigBuilder, Parse, Value}; use serde::Deserialize; use std::borrow::Cow;

[derive(Deserialize)]

struct Conf { id: u32, logger: String, tag: String, }

struct JsonStringParser<'a> { data: Cow<'a, str>, }

impl<'a> JsonStringParser<'a> { pub fn new(data: impl Into>) -> Self { JsonStringParser { data: data.into() } } }

impl Case for JsonStringParser<'_> {}

impl Parse for JsonStringParser<'> { fn parse(&mut self, _value: &Value) -> AnyResult { Ok(serdejson::from_str(&self.data)?) } }

let data = r#"{ "id": 42, "logger": "file", "tag": "test" }"#; let config = ConfigBuilder::loadone(JsonStringParser::new(data))?; let confdata: Conf = config.get()?; ```

JSON parser get partial data

To enable parsers used in example below, one has to add the following to Cargo.toml:

toml [dependencies] irx-config = { version = "1.0", features = ["json"] }

```rust use irxconfig::parsers::json; use irxconfig::ConfigBuilder; use serde::Deserialize;

[derive(Deserialize)]

struct Logger { level: String, path: String, }

[derive(Deserialize)]

struct Connection { #[serde(default = "localhost")] host: String, port: u16, }

let config = ConfigBuilder::loadone( json::ParserBuilder::default() .defaultpath("config.json") .build()?, )?;

let logger: Logger = config.getbykeypath("logger")?.unwrap(); let port: u16 = config.getbykeypath("connection:port")?.unwrap(); ```