feat: warn or exit on config file parse errors

The relay will now fail to start if an invalid config file is
explicitly provided.  If the file was read implicitly from the current
directory, a warning will be provided, but the relay will still startup.

src/bin/bulkloader.rs

@@ -20,7 +20,7 @@ pub fn main() -> Result<()> {
     let _trace_sub = tracing_subscriber::fmt::try_init();
     println!("Nostr-rs-relay Bulk Loader");
     // check for a database file, or create one.
-    let settings = config::Settings::new(&None);
+    let settings = config::Settings::new(&None)?;
     if !Path::new(&settings.database.data_directory).is_dir() {
         info!("Database directory does not exist");
         return Err(Error::DatabaseDirError);

src/config.rs

@@ -1,10 +1,8 @@
 //! Configuration file and settings management
+use crate::payment::Processor;
 use config::{Config, ConfigError, File};
 use serde::{Deserialize, Serialize};
 use std::time::Duration;
-use tracing::warn;
-
-use crate::payment::Processor;
 
 #[derive(Debug, Serialize, Deserialize, Clone)]
 #[allow(unused)]
@@ -193,17 +191,23 @@ pub struct Settings {
 }
 
 impl Settings {
-    #[must_use]
+    pub fn new(config_file_name: &Option<String>) -> Result<Self, ConfigError> {
-    pub fn new(config_file_name: &Option<String>) -> Self {
         let default_settings = Self::default();
         // attempt to construct settings with file
         let from_file = Self::new_from_default(&default_settings, config_file_name);
         match from_file {
-            Ok(f) => f,
             Err(e) => {
-                warn!("Error reading config file ({:?})", e);
+                // pass up the parse error if the config file was specified,
-                default_settings
+                // otherwise use the default config (with a warning).
+                if config_file_name.is_some() {
+                    Err(e)
+                } else {
+                    eprintln!("Error reading config file ({:?})", e);
+                    eprintln!("WARNING: Default configuration settings will be used");
+                    Ok(default_settings)
+                }
             }
+            ok => ok,
         }
     }
 

src/main.rs

@@ -4,12 +4,12 @@ use console_subscriber::ConsoleLayer;
 use nostr_rs_relay::cli::CLIArgs;
 use nostr_rs_relay::config;
 use nostr_rs_relay::server::start_server;
+use std::fs;
+use std::path::Path;
+use std::process;
 use std::sync::mpsc as syncmpsc;
 use std::sync::mpsc::{Receiver as MpscReceiver, Sender as MpscSender};
 use std::thread;
-use std::path::Path;
-use std::fs;
-use std::process;
 #[cfg(not(target_env = "msvc"))]
 use tikv_jemallocator::Jemalloc;
 use tracing::info;
@@ -27,36 +27,35 @@ fn main() {
     // get config file name from args
     let config_file_arg = args.config;
 
-    // Quits if config file path is unreadable or does not exist
+    // Ensure the config file is readable if it was explicitly set
-    let config_file_path = config_file_arg.as_ref().map(|x| &**x).unwrap();
+    if let Some(config_path) = config_file_arg.as_ref() {
-    let path = Path::new(&config_file_path);
+        let path = Path::new(&config_path);
-
+        if !path.exists() {
-    if !path.exists() {
+            eprintln!("Config file not found: {}", &config_path);
-        eprintln!("Config file not found: {}", &config_file_path);
+            process::exit(1);
-        process::exit(1);
+        }
+        if !path.is_file() {
+            eprintln!("Invalid config file path: {}", &config_path);
+            process::exit(1);
+        }
+        if let Err(err) = fs::metadata(path) {
+            eprintln!("Error while accessing file metadata: {}", err);
+            process::exit(1);
+        }
+        if let Err(err) = fs::File::open(path) {
+            eprintln!("Config file is not readable: {}", err);
+            process::exit(1);
+        }
     }
 
-    if !path.is_file() {
-        eprintln!("Invalid config file path: {}", &config_file_path);
-        process::exit(1);
-    }
-
-    if let Err(err) = fs::metadata(&path) {
-        eprintln!("Error while accessing file metadata: {}", err);
-        process::exit(1);
-    }
-
-    if let Err(err) = fs::File::open(&path) {
-        eprintln!("Config file is not readable: {}", err);
-        process::exit(1);
-    }
-
-
     let mut _log_guard: Option<WorkerGuard> = None;
 
     // configure settings from the config file (defaults to config.toml)
     // replace default settings with those read from the config file
-    let mut settings = config::Settings::new(&config_file_arg);
+    let mut settings = config::Settings::new(&config_file_arg).unwrap_or_else(|e| {
+        eprintln!("Error reading config file ({:?})", e);
+        process::exit(1);
+    });
 
     // setup tracing
     if settings.diagnostics.tracing {