fix(clippy): split code a bit

Main was too big for clippy

Cargo.lock

@@ -185,9 +185,9 @@ checksum = "d71b6127be86fdcfddb610f7182ac57211d4b18a3e9c82eb2d17662f2227ad6a"
 
 [[package]]
 name = "cc"
-version = "1.2.25"
+version = "1.2.26"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "d0fc897dc1e865cc67c0e05a836d9d3f1df3cbe442aa4a9473b18e12624a4951"
+checksum = "956a5e21988b87f372569b66183b78babf23ebc2e744b733e4350a752c4dafac"
 dependencies = [
  "shlex",
 ]
@@ -834,9 +834,9 @@ checksum = "bbbb5d9659141646ae647b42fe094daf6c6192d1620870b449d9557f748b2daa"
 
 [[package]]
 name = "smallvec"
-version = "1.15.0"
+version = "1.15.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "8917285742e9f3e1683f0a9c4e6b57960b7314d0b08d30d1ecd426713ee2eee9"
+checksum = "67b1b7a3b5fe4f1376887184045fcf45c69e92af734b7aaddc05fb777b6fbd03"
 
 [[package]]
 name = "socket2"
@@ -1027,9 +1027,9 @@ dependencies = [
 
 [[package]]
 name = "tracing-attributes"
-version = "0.1.28"
+version = "0.1.29"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "395ae124c09f9e6918a2310af6038fba074bcf474ac352496d5910dd59a2226d"
+checksum = "1b1ffbcf9c6f6b99d386e7444eb608ba646ae452a36b39737deb9663b610f662"
 dependencies = [
  "proc-macro2",
  "quote",
@@ -1038,9 +1038,9 @@ dependencies = [
 
 [[package]]
 name = "tracing-core"
-version = "0.1.33"
+version = "0.1.34"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "e672c95779cf947c5311f83787af4fa8fffd12fb27e4993211a84bdfd9610f9c"
+checksum = "b9d12581f227e93f094d3af2ae690a574abb8a2b9b7a96e7cfe9647b2b617678"
 dependencies = [
  "once_cell",
  "valuable",

flake.lock

@@ -37,11 +37,11 @@
     },
     "nixpkgs": {
       "locked": {
-        "lastModified": 1749008870,
-        "narHash": "sha256-5QEAcgawS2tOJrLr+U5DtzlShSCEpeg7PZDC7txvLQs=",
-        "rev": "c2a03962b8e24e669fb37b7df10e7c79531ff1a4",
+        "lastModified": 1749238035,
+        "narHash": "sha256-+w+VydE8NSQXu8RSNLhn0fVMaEoFPgUbNYa8m1rewuM=",
+        "rev": "d3d2d80a2191a73d1e86456a751b83aa13085d7d",
         "type": "tarball",
-        "url": "https://releases.nixos.org/nixos/unstable/nixos-25.11pre810143.c2a03962b8e2/nixexprs.tar.xz?rev=c2a03962b8e24e669fb37b7df10e7c79531ff1a4"
+        "url": "https://releases.nixos.org/nixos/unstable/nixos-25.11pre811203.d3d2d80a2191/nixexprs.tar.xz?rev=d3d2d80a2191a73d1e86456a751b83aa13085d7d"
       },
       "original": {
         "type": "tarball",
@@ -65,11 +65,11 @@
         ]
       },
       "locked": {
-        "lastModified": 1749091064,
-        "narHash": "sha256-TGtYjzRX0sueFhwYsnNNFF5TTKnpnloznpIghLzxeXo=",
+        "lastModified": 1749177458,
+        "narHash": "sha256-9HNq3EHZIvvxXQyEn0sYOywcESF1Xqw2Q8J1ZewcXuk=",
         "owner": "oxalica",
         "repo": "rust-overlay",
-        "rev": "12419593ce78f2e8e1e89a373c6515885e218acb",
+        "rev": "d58933b88cef7a05e9677e94352fd6fedba402cd",
         "type": "github"
       },
       "original": {
@@ -100,11 +100,11 @@
         ]
       },
       "locked": {
-        "lastModified": 1748243702,
-        "narHash": "sha256-9YzfeN8CB6SzNPyPm2XjRRqSixDopTapaRsnTpXUEY8=",
+        "lastModified": 1749194973,
+        "narHash": "sha256-eEy8cuS0mZ2j/r/FE0/LYBSBcIs/MKOIVakwHVuqTfk=",
         "owner": "numtide",
         "repo": "treefmt-nix",
-        "rev": "1f3f7b784643d488ba4bf315638b2b0a4c5fb007",
+        "rev": "a05be418a1af1198ca0f63facb13c985db4cb3c5",
         "type": "github"
       },
       "original": {

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,