Reduce amount of blocking in blocks

src/blocks/amd_gpu.rs

@@ -63,7 +63,7 @@ pub async fn run(config: &Config, api: &CommonApi) -> Result<()> {
     };
 
     let device = match &config.device {
-        Some(name) => Device::new(name)?,
+        Some(name) => Device::new(name).await?,
         None => Device::default_card()
             .await
             .error("failed to get default GPU")?
@@ -121,10 +121,10 @@ struct GpuInfo {
 }
 
 impl Device {
-    fn new(name: &str) -> Result<Self, Error> {
+    async fn new(name: &str) -> Result<Self, Error> {
         let path = PathBuf::from(format!("/sys/class/drm/{name}/device"));
 
-        if !path.exists() {
+        if !file_exists(&path).await {
             Err(Error::new(format!("Device {name} not found")))
         } else {
             Ok(Self { path })
@@ -185,9 +185,9 @@ impl Device {
 mod tests {
     use super::*;
 
-    #[test]
-    fn test_non_existing_gpu_device() {
-        let device = Device::new("/nope");
+    #[tokio::test]
+    async fn test_non_existing_gpu_device() {
+        let device = Device::new("/nope").await;
         assert!(device.is_err());
     }
 }

src/blocks/calendar.rs

@@ -295,7 +295,7 @@ pub async fn run(config: &Config, api: &CommonApi) -> Result<()> {
     let warning_threshold = Duration::try_seconds(config.warning_threshold.into())
         .error("Invalid warning threshold configuration")?;
 
-    let mut source = Source::new(source_config.clone()).await?;
+    let mut source = Source::new(source_config.to_owned()).await?;
 
     let mut timer = config.fetch_interval.timer();
 
@@ -424,7 +424,8 @@ impl Source {
                 credentials_path,
             }) => {
                 let credentials = if let Some(path) = credentials_path {
-                    util::deserialize_toml_file(path.expand()?.to_string())
+                    util::async_deserialize_toml_file(path.expand()?.to_string())
+                        .await
                         .error("Failed to read basic credentials file")?
                 } else {
                     credentials.clone()
@@ -440,7 +441,8 @@ impl Source {
             }
             AuthConfig::OAuth2(oauth2) => {
                 let credentials = if let Some(path) = &oauth2.credentials_path {
-                    util::deserialize_toml_file(path.expand()?.to_string())
+                    util::async_deserialize_toml_file(path.expand()?.to_string())
+                        .await
                         .error("Failed to read oauth2 credentials file")?
                 } else {
                     oauth2.credentials.clone()

src/blocks/packages/apt.rs

@@ -50,7 +50,7 @@ impl Apt {
     async fn setup(&mut self) -> Result<()> {
         let mut cache_dir = env::temp_dir();
         cache_dir.push("i3rs-apt");
-        if !cache_dir.exists() {
+        if !file_exists(&cache_dir).await {
             create_dir_all(&cache_dir)
                 .await
                 .error("Failed to create temp dir")?;

src/blocks/packages/pacman.rs

@@ -72,7 +72,7 @@ impl Backend for Pacman {
 
         // Create symlink to local cache in `checkup-db` if required
         let local_cache = PACMAN_UPDATES_DB.join("local");
-        if !local_cache.exists() {
+        if !file_exists(&local_cache).await {
             symlink(PACMAN_DB.join("local"), local_cache)
                 .await
                 .error("Failed to created required symlink")?;

src/blocks/prelude.rs

@@ -3,7 +3,7 @@ pub use super::{BlockAction, CommonApi};
 pub use crate::click::MouseButton;
 pub use crate::errors::*;
 pub use crate::formatting::{config::Config as FormatConfig, value::Value, Values};
-pub use crate::util::{default, new_dbus_connection, new_system_dbus_connection};
+pub use crate::util::{default, file_exists, new_dbus_connection, new_system_dbus_connection};
 pub use crate::widget::{State, Widget};
 pub use crate::wrappers::{Seconds, ShellString};
 pub(crate) use crate::REQWEST_CLIENT;

src/netlink.rs

@@ -77,7 +77,7 @@ impl NetDevice {
         let path = Path::new("/sys/class/net").join(&iface.name);
         let tun = iface.name.starts_with("tun")
             || iface.name.starts_with("tap")
-            || path.join("tun_flags").exists();
+            || util::file_exists(path.join("tun_flags")).await;
         let (wg, ppp) = util::read_file(path.join("uevent"))
             .await
             .map_or((false, false), |c| {

src/util.rs

@@ -7,6 +7,10 @@ use tokio::process::Command;
 
 use crate::errors::*;
 
+pub async fn file_exists(path: impl AsRef<Path>) -> bool {
+    tokio::fs::metadata(path).await.is_ok()
+}
+
 /// Tries to find a file in standard locations:
 /// - Fist try to find a file by full path (only if path is absolute)
 /// - Then try XDG_CONFIG_HOME (e.g. `~/.config`)
@@ -95,6 +99,27 @@ where
     let contents = std::fs::read_to_string(path)
         .or_error(|| format!("Failed to read file: {}", path.display()))?;
 
+    deserialize_toml_file_string(contents, path)
+}
+
+pub async fn async_deserialize_toml_file<T, P>(path: P) -> Result<T>
+where
+    T: DeserializeOwned,
+    P: AsRef<Path>,
+{
+    let path = path.as_ref();
+
+    let contents = read_file(path)
+        .await
+        .or_error(|| format!("Failed to read file: {}", path.display()))?;
+
+    deserialize_toml_file_string(contents, path)
+}
+
+fn deserialize_toml_file_string<T>(contents: String, path: &Path) -> Result<T>
+where
+    T: DeserializeOwned,
+{
     toml::from_str(&contents).map_err(|err| {
         let location_msg = err
             .span()