Allow loading config from file

.gitignore

@@ -1,5 +1,5 @@
 /.direnv/
 /result*
-/*.local
+/*.local*
 /debug/
 /target/

src/config.rs

@@ -1,6 +1,6 @@
 //! Application configuration.
 
-use std::time::Duration;
+use std::{path::PathBuf, time::Duration};
 
 use anyhow::{Context, Result};
 use config::Config;
@@ -48,15 +48,25 @@ pub struct AppConfig {
 }
 
 /// Load application configuration.
-pub fn load_config() -> Result<AppConfig> {
-    let config = Config::builder()
-        .add_source(
-            config::Environment::with_prefix("FS")
-                .separator("__")
-                .list_separator(","),
-        )
-        .build()
-        .context("failed to load config")?;
+pub fn load_config(config_path: &Option<PathBuf>) -> Result<AppConfig> {
+    let mut config_builder = Config::builder().add_source(
+        config::Environment::with_prefix("FS")
+            .separator("__")
+            .list_separator(","),
+    );
+
+    match config_path {
+        Some(path) => {
+            config_builder =
+                config_builder.add_source(config::File::from(path.clone()).required(true));
+        }
+        None => {
+            config_builder =
+                config_builder.add_source(config::File::with_name("config").required(false));
+        }
+    }
+
+    let config = config_builder.build().context("failed to load config")?;
 
     debug!("Raw configuration: {:#?}", config);
 

src/log_setup.rs

@@ -10,10 +10,12 @@ use std::env;
 /// # Panics
 ///
 /// Function should not panic. On error, logging is just disabled.
-pub fn configure_logging() -> Result<()> {
+pub fn configure_logging(log_level: &Option<String>) -> Result<()> {
     let mut builder = formatted_builder();
 
-    if let Ok(s) = env::var("FS__LOG") {
+    if let Some(s) = log_level {
+        builder.parse_filters(s);
+    } else if let Ok(s) = env::var("FS__LOG") {
         builder.parse_filters(&s);
     } else {
         builder.filter_level(LevelFilter::Info);

src/main.rs

@@ -43,6 +43,12 @@ pub const VERSION: &str = env!("CARGO_PKG_VERSION");
 struct Cli {
     #[command(subcommand)]
     command: Option<Commands>,
+    /// Path to the configuration file.
+    #[arg(short, long, default_value = "None")]
+    config: Option<PathBuf>,
+    /// Log level. Takes precedence over the FS__LOG env variable. Default is INFO.
+    #[arg(long, default_value = "None")]
+    log_level: Option<String>,
 }
 #[derive(Subcommand)]
 enum Commands {
@@ -73,17 +79,17 @@ async fn crawler_loop(crawler: Arc<Crawler>) {
 
 #[tokio::main]
 async fn main() -> Result<()> {
-    configure_logging().ok();
-
     let cli = Cli::parse();
 
+    configure_logging(&cli.log_level).ok();
+
     match &cli.command {
         Some(Commands::Serve {
             services,
             listen,
             workers,
         }) => {
-            let config = load_config().context("failed to load config")?;
+            let config = load_config(&cli.config).context("failed to load config")?;
 
             let listen: SocketAddr = listen
                 .unwrap_or_else(|| SocketAddr::V4(SocketAddrV4::new([127, 0, 0, 1].into(), 8080)));