fix(clippy): split code a bit

Main was too big for clippy

src/main.rs

@@ -128,7 +128,7 @@ impl SavedIPs {
             .chain(self.ipv6.map(IpAddr::V6))
     }
 
-    fn from_str(data: &str) -> miette::Result<Self> {
+    fn from_str(data: &str) -> Result<Self> {
         match data.parse::<IpAddr>() {
             // Old format
             Ok(IpAddr::V4(ipv4)) => Ok(Self {
@@ -145,7 +145,7 @@ impl SavedIPs {
 }
 
 impl AppState<'static> {
-    fn from_args(args: &Opts, config: &config::Config) -> miette::Result<Self> {
+    fn from_args(args: &Opts, config: &config::Config) -> Result<Self> {
         let Opts {
             verbosity: _,
             data_dir,
@@ -180,7 +180,7 @@ impl AppState<'static> {
             // Load keyfile
             key_file: key_file
                 .as_deref()
-                .map(|path| -> miette::Result<_> {
+                .map(|path| -> Result<_> {
                     std::fs::File::open(path)
                         .into_diagnostic()
                         .wrap_err_with(|| {
@@ -255,6 +255,18 @@ impl std::str::FromStr for Ipv6Prefix {
     }
 }
 
+fn load_password(path: &Path) -> Result<Box<[u8]>> {
+    let pass = std::fs::read_to_string(path).into_diagnostic()?;
+
+    let pass: Box<[u8]> = URL_SAFE_NO_PAD
+        .decode(pass.trim().as_bytes())
+        .into_diagnostic()
+        .wrap_err_with(|| format!("failed to decode password from {}", path.display()))?
+        .into();
+
+    Ok(pass)
+}
+
 #[tracing::instrument(err)]
 fn main() -> Result<()> {
     // set panic hook to pretty print with miette's formatter
@@ -310,18 +322,8 @@ fn main() -> Result<()> {
     let password_hash = config
         .password
         .password_file
-        .map(|path| -> miette::Result<_> {
-            let path = path.as_path();
-            let pass = std::fs::read_to_string(path).into_diagnostic()?;
-
-            let pass: Box<[u8]> = URL_SAFE_NO_PAD
-                .decode(pass.trim().as_bytes())
-                .into_diagnostic()
-                .wrap_err_with(|| format!("failed to decode password from {}", path.display()))?
-                .into();
-
-            Ok(pass)
-        })
+        .as_deref()
+        .map(load_password)
         .transpose()
         .wrap_err("failed to load password hash")?;
 
@@ -336,63 +338,70 @@ fn main() -> Result<()> {
         .into_diagnostic()
         .wrap_err("failed to start the tokio runtime")?;
 
-    rt.block_on(async {
-        // Update DNS record with previous IPs (if available)
-        let ips = state.last_ips.lock().await.clone();
+    rt.block_on(async_main(state, config, password_hash))
+        .wrap_err("failed to run main loop")
+}
 
-        let mut actions = ips
-            .ips()
-            .filter(|ip| config.records.ip_type.valid_for_type(*ip))
-            .flat_map(|ip| nsupdate::Action::from_records(ip, state.ttl, state.records))
-            .peekable();
+#[tracing::instrument(err, skip(state, pass))]
+async fn async_main(
+    state: AppState<'static>,
+    config: Config,
+    pass: Option<Box<[u8]>>,
+) -> Result<()> {
+    // Update DNS record with previous IPs (if available)
+    let ips = state.last_ips.lock().await.clone();
 
-        if actions.peek().is_some() {
-            match nsupdate::nsupdate(state.key_file, actions).await {
-                Ok(status) => {
-                    if !status.success() {
-                        error!("nsupdate failed: code {status}");
-                        bail!("nsupdate returned with code {status}");
-                    }
-                }
-                Err(err) => {
-                    error!("Failed to update records with previous IP: {err}");
-                    return Err(err)
-                        .into_diagnostic()
-                        .wrap_err("failed to update records with previous IP");
+    let mut actions = ips
+        .ips()
+        .filter(|ip| config.records.ip_type.valid_for_type(*ip))
+        .flat_map(|ip| nsupdate::Action::from_records(ip, state.ttl, state.records))
+        .peekable();
+
+    if actions.peek().is_some() {
+        match nsupdate::nsupdate(state.key_file, actions).await {
+            Ok(status) => {
+                if !status.success() {
+                    error!("nsupdate failed: code {status}");
+                    bail!("nsupdate returned with code {status}");
                 }
             }
+            Err(err) => {
+                error!("Failed to update records with previous IP: {err}");
+                return Err(err)
+                    .into_diagnostic()
+                    .wrap_err("failed to update records with previous IP");
+            }
         }
+    }
 
-        // Create services
-        let app = Router::new().route("/update", get(update_records));
-        // if a password is provided, validate it
-        let app = if let Some(pass) = password_hash {
-            app.layer(auth::layer(
-                Box::leak(pass),
-                Box::leak(config.password.salt),
-            ))
-        } else {
-            app
-        }
-        .layer(config.records.ip_source.into_extension())
-        .with_state(state);
+    // Create services
+    let app = Router::new().route("/update", get(update_records));
+    // if a password is provided, validate it
+    let app = if let Some(pass) = pass {
+        app.layer(auth::layer(
+            Box::leak(pass),
+            Box::leak(config.password.salt),
+        ))
+    } else {
+        app
+    }
+    .layer(config.records.ip_source.into_extension())
+    .with_state(state);
 
-        let config::Server { address } = config.server;
+    let config::Server { address } = config.server;
 
-        // Start services
-        info!("starting listener on {address}");
-        let listener = tokio::net::TcpListener::bind(address)
-            .await
-            .into_diagnostic()?;
-        info!("listening on {address}");
-        axum::serve(
-            listener,
-            app.into_make_service_with_connect_info::<SocketAddr>(),
-        )
+    // Start services
+    info!("starting listener on {address}");
+    let listener = tokio::net::TcpListener::bind(address)
         .await
-        .into_diagnostic()
-    })
-    .wrap_err("failed to run main loop")
+        .into_diagnostic()?;
+    info!("listening on {address}");
+    axum::serve(
+        listener,
+        app.into_make_service_with_connect_info::<SocketAddr>(),
+    )
+    .await
+    .into_diagnostic()
 }
 
 /// Serde deserialization decorator to map empty Strings to None,