add: print config command

Author: zk-steve

README.md

@@ -18,10 +18,14 @@ This will display the available options for running the server:
 ```
 Simple REST server
 
-Usage: cli [OPTIONS]
+Usage: cli [OPTIONS] [COMMAND]
+
+Commands:
+  config  Print config
+  help    Print this message or the help of the given subcommand(s)
 
 Options:
-  -c, --config-file <CONFIG_FILE>  Config file [default: config/default.toml]
+  -c, --config-path <CONFIG_PATH>  Config file [default: config/default.toml]
   -v, --version                    Print version
   -h, --help                       Print help
 ```

cli/src/main.rs

@@ -26,7 +26,7 @@ mod telemetry;
 use crate::options::Options;
 use crate::telemetry::init_telemetry;
 
-use clap::Parser;
+use clap::{Parser, Subcommand};
 
 use deadpool_diesel::postgres::{Pool, Runtime};
 use deadpool_diesel::Manager;
@@ -46,6 +46,8 @@ use tracing::{error, info};
 #[derive(Parser, Debug)]
 #[command(about, long_about = None)]
 struct Args {
+    #[command(subcommand)]
+    command: Option<Commands>,
     /// Config file
     #[arg(short, long, default_value = "config/default.toml")]
     config_path: Vec<String>,
@@ -54,6 +56,12 @@ struct Args {
     version: bool,
 }
 
+#[derive(Subcommand, Clone, Debug)]
+enum Commands {
+    /// Print config
+    Config,
+}
+
 /// Entry point for running the server.
 #[tokio::main]
 async fn main() {
@@ -62,14 +70,20 @@ async fn main() {
         println!(env!("APP_VERSION"));
         return;
     }
+
     let options = match Options::new(args.config_path) {
         Ok(options) => options,
         Err(err) => {
-            error!("Failed to load config: {}", err);
+            println!("Failed to load config: {}", err);
             return;
         }
     };
 
+    if let Some(Commands::Config) = args.command {
+        println!("{:#?}", options);
+        return;
+    }
+
     init_telemetry(
         options.service_name.as_str(),
         options.exporter_endpoint.as_str(),