Show supported features and audio backend in --version

Cargo.toml

@@ -36,6 +36,7 @@ librespot-connect = { version = "0.4" }
 toml = "0.7"
 color-eyre = "0.6"
 directories = "5.0.1"
+once_cell = "1.20.2"
 
 [target."cfg(unix)".dependencies]
 daemonize = "0.5"

src/config.rs

@@ -13,6 +13,7 @@ use librespot_playback::{
     dither::{mk_ditherer, DithererBuilder, TriangularDitherer},
 };
 use log::{error, info, warn};
+use once_cell::sync::Lazy;
 use serde::{de::Error, de::Unexpected, Deserialize, Deserializer};
 use sha1::{Digest, Sha1};
 use std::{fmt, fs, path::Path, path::PathBuf, str::FromStr};
@@ -332,34 +333,102 @@ impl From<AudioFormat> for LSAudioFormat {
     }
 }
 
-#[derive(Debug, Default, StructOpt)]
+pub static ABOUT_INFO: Lazy<String> = Lazy::new(format_features_info);
+
+// Features functionality
+fn format_features_info() -> String {
+    let features = get_enabled_features();
+    let backends = get_enabled_backends();
+
+    let features_str = if features.is_empty() {
+        "none".to_string()
+    } else {
+        features.join(", ")
+    };
+
+    // Get the version from the Cargo environment variable
+    let version = env!("CARGO_PKG_VERSION");
+
+    // Format the string with version under the title, and avoid repeating version elsewhere
+    format!(
+        "A Spotify daemon\nspotifyd {}\nfeatures: {}\naudio backends: {}",
+        version,
+        features_str,
+        backends.join(", ")
+    )
+}
+
+pub fn get_enabled_backends() -> Vec<&'static str> {
+    let backends = vec![
+        #[cfg(feature = "alsa_backend")]
+        "alsa",
+        #[cfg(feature = "pulseaudio_backend")]
+        "pulseaudio",
+        #[cfg(feature = "rodio_backend")]
+        "rodio",
+        #[cfg(feature = "portaudio_backend")]
+        "portaudio",
+        #[cfg(feature = "rodiojack_backend")]
+        "rodiojack",
+        #[cfg(feature = "pipe_backend")]
+        "pipe",
+    ];
+
+    backends
+}
+
+pub fn get_enabled_features() -> Vec<&'static str> {
+    let mut features = Vec::new();
+
+    #[cfg(feature = "dbus_mpris")]
+    features.push("MPRIS");
+
+    #[cfg(feature = "dbus_keyring")]
+    features.push("keyring");
+
+    features
+}
+
+#[derive(Debug, StructOpt)]
 #[structopt(
-    about = "A Spotify daemon",
+    about = &**ABOUT_INFO, // Use double dereference to get `&str`
     author,
     name = "spotifyd",
     setting(AppSettings::ColoredHelp)
 )]
 pub struct CliConfig {
-    /// The path to the config file to use
+    // The path to the config file to use
     #[structopt(long, value_name = "string")]
     pub config_path: Option<PathBuf>,
 
-    /// If set, starts spotifyd without detaching
+    // If set, starts spotifyd without detaching
     #[structopt(long)]
     pub no_daemon: bool,
 
-    /// Prints more verbose output
+    // Prints more verbose output
     #[structopt(long)]
     pub verbose: bool,
 
-    /// Path to PID file.
+    // Path to PID file.
     #[structopt(long)]
     pub pid: Option<PathBuf>,
 
     #[structopt(flatten)]
     pub shared_config: SharedConfigValues,
 }
 
+impl Default for CliConfig {
+    fn default() -> Self {
+        CliConfig {
+            config_path: None,
+            no_daemon: false,
+            verbose: false,
+            pid: None,
+            shared_config: SharedConfigValues::default(),
+        }
+    }
+}
+
 // A struct that holds all allowed config fields.
 // The actual config file is made up of two sections, spotifyd and global.
 #[derive(Clone, Default, Deserialize, PartialEq, StructOpt)]

src/main.rs

@@ -1,4 +1,5 @@
 use crate::config::CliConfig;
+use crate::config::ABOUT_INFO;
 #[cfg(unix)]
 use color_eyre::eyre::eyre;
 use color_eyre::{
@@ -98,6 +99,12 @@ fn main() -> eyre::Result<()> {
 
     color_eyre::install().wrap_err("Couldn't initialize error reporting")?;
 
+    // Handle --version explicitly
+    if std::env::args().any(|arg| arg == "--version") {
+        println!("{}", &**ABOUT_INFO);
+        return Ok(());
+    }
+
     let mut cli_config: CliConfig = CliConfig::from_args();
 
     let is_daemon = !cli_config.no_daemon;