Adding clap for parameter parsing

Cargo.lock

@@ -222,6 +222,46 @@ dependencies = [
  "windows-link",
 ]
 
+[[package]]
+name = "clap"
+version = "4.5.54"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "c6e6ff9dcd79cff5cd969a17a545d79e84ab086e444102a591e288a8aa3ce394"
+dependencies = [
+ "clap_builder",
+ "clap_derive",
+]
+
+[[package]]
+name = "clap_builder"
+version = "4.5.54"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "fa42cf4d2b7a41bc8f663a7cab4031ebafa1bf3875705bfaf8466dc60ab52c00"
+dependencies = [
+ "anstream",
+ "anstyle",
+ "clap_lex",
+ "strsim",
+]
+
+[[package]]
+name = "clap_derive"
+version = "4.5.49"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "2a0b5487afeab2deb2ff4e03a807ad1a03ac532ff5a2cee5d86884440c7f7671"
+dependencies = [
+ "heck",
+ "proc-macro2",
+ "quote",
+ "syn",
+]
+
+[[package]]
+name = "clap_lex"
+version = "0.7.7"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "c3e64b0cc0439b12df2fa678eae89a1c56a529fd067a9115f7827f1fffd22b32"
+
 [[package]]
 name = "cloudabi"
 version = "0.0.3"
@@ -726,6 +766,12 @@ dependencies = [
  "hashbrown 0.16.1",
 ]
 
+[[package]]
+name = "heck"
+version = "0.5.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "2304e00983f87ffb38b55b444b5e3b60a884b5d30c0fca7d82fe33449bbe55ea"
+
 [[package]]
 name = "hermit-abi"
 version = "0.5.2"
@@ -1291,6 +1337,7 @@ name = "oott"
 version = "0.1.0"
 dependencies = [
  "chrono",
+ "clap",
  "config",
  "duration-string",
  "env_logger",
@@ -2066,6 +2113,12 @@ version = "1.2.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "6ce2be8dc25455e1f91df71bfa12ad37d7af1092ae736f3a6cd0e37bc7810596"
 
+[[package]]
+name = "strsim"
+version = "0.11.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "7da8b5736845d9f2fcb837ea5d9e2628564b3b043a70948a3f0b778838c5fb4f"
+
 [[package]]
 name = "syn"
 version = "2.0.114"

Cargo.toml

@@ -18,3 +18,4 @@ pushover = "0.4.0"
 config = "0.15.19"
 lazy_static = "1.5.0"
 duration-string = { version="0.5.3", features = ["serde"] }
+clap = {version="4.5.54", features=["derive"]}

src/settings.rs

@@ -1,7 +1,8 @@
+use clap::Parser;
 use config::{Config, ConfigError, File};
 use duration_string::DurationString;
 use lazy_static::lazy_static;
-use log::error;
+use log::{error, info};
 use serde::Deserialize;
 
 // -----------------------------------------------------------
@@ -47,12 +48,27 @@ pub struct Settings {
 // End configuration structure
 // -----------------------------------------------------------
 
-const CONFIG_FILE_PATH: &str = "./oott.toml";
+// Command line parameters relevant to configuration
+#[derive(Parser, Debug)]
+#[command(version, about, long_about = None)]
+struct Args {
+    /// Config file path
+    #[arg(short, long)]
+    config: Option<String>,
+}
+
+const DEFAULT_CONFIG_FILE_PATH: &str = "./oott.toml";
 
 impl Settings {
     pub fn new() -> Result<Self, ConfigError> {
+        let args = Args::parse();
+
+        let config_path = args.config.unwrap_or(DEFAULT_CONFIG_FILE_PATH.to_string());
+
+        info!("Reading configuration from {}", config_path);
+
         let local_settings = Config::builder()
-            .add_source(File::with_name(CONFIG_FILE_PATH))
+            .add_source(File::with_name(config_path.as_str()))
             .build()?;
 
         local_settings.try_deserialize()
@@ -63,8 +79,8 @@ lazy_static! {
     pub static ref CONFIG: Settings = match Settings::new() {
         Ok(value) => value,
         Err(error) => {
-            error!("Error reading configuration file ({CONFIG_FILE_PATH}): {error}");
-            panic!("Error reading configuration file ({CONFIG_FILE_PATH}): {error}");
+            error!("Error reading configuration file: {error}");
+            panic!("Error reading configuration file: {error}");
         }
     };
 }