Switch to a more standard (?) binary crate layout

Cargo.toml

@@ -7,4 +7,8 @@ edition = "2021"
 
 [dependencies]
 clap = { version = "3.1.6", features = ["derive"]  }
-regex = { version = "*" }
+config = { version = "0.13.1" }
+serde_derive = { version = "1.0.8" }
+serde = { version = "*" }
+
+[dev-dependencies]

src/main.rs

@@ -1,12 +1,17 @@
-use carman::Arguments;
 use clap::Parser;
 
 /// Carman code deployment Daemon
+mod arguments;
+use arguments::Arguments;
 
+mod settings;
+use settings::Settings;
 
 fn main() {
     let args = Arguments::parse();
+    let config = Settings::new();
 
     println!("Hello, world!");
     println!("{:?}", args);
+    println!("{:?}", config);
 }

src/settings/mod.rs

@@ -0,0 +1,53 @@
+use config::{Config, ConfigError, Environment, File};
+use serde_derive::Deserialize;
+use std::env;
+
+#[derive(Debug, Deserialize)]
+#[allow(unused)]
+struct Repository {
+    key: String,
+    token: String,
+    url: String,
+    version: u8,
+}
+
+#[derive(Debug, Deserialize)]
+#[allow(unused)]
+pub struct Settings {
+    debug: bool,
+    log: u8,
+    repository: Repository,
+}
+
+impl Settings {
+    pub fn new() -> Result<Self, ConfigError> {
+        let run_mode = env::var("RUN_MODE").unwrap_or_else(|_| "development".into());
+
+        let s = Config::builder()
+            // Start off by merging in the "default" configuration file
+            .add_source(File::with_name("examples/hierarchical-env/config/default"))
+            // Add in the current environment file
+            // Default to 'development' env
+            // Note that this file is _optional_
+            .add_source(
+                File::with_name(&format!("examples/hierarchical-env/config/{}", run_mode))
+                    .required(false),
+            )
+            // Add in a local configuration file
+            // This file shouldn't be checked in to git
+            .add_source(File::with_name("examples/hierarchical-env/config/local").required(false))
+            // Add in settings from the environment (with a prefix of APP)
+            // Eg.. `APP_DEBUG=1 ./target/app` would set the `debug` key
+            .add_source(Environment::with_prefix("carman"))
+            // You may also programmatically change settings
+            .set_override("database.url", "postgres://")?
+            .build()?;
+
+        // Now that we're done, let's access our configuration
+        println!("debug: {:?}", s.get_bool("debug"));
+        println!("database: {:?}", s.get::<String>("database.url"));
+
+        // You can deserialize (and thus freeze) the entire configuration as
+        s.try_deserialize()
+    }
+}