feat: custom error handling, logging with tracing

Cargo.toml

@@ -4,3 +4,4 @@ members = [
     "winapps-cli",
     "winapps-gui",
 ]
+resolver = "2"

winapps/Cargo.toml

@@ -6,7 +6,11 @@ edition = "2021"
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
 
 [dependencies]
+anyhow = "1.0.75"
 derive-new = "0.5.9"
 home = "0.5.5"
+lazy_static = "1.4.0"
 serde = { version = "1.0.171", features = ["derive"] }
-toml = "0.7.6"
+thiserror = "1.0.49"
+toml = "0.8.2"
+tracing = "0.1.37"

winapps/src/errors.rs

@@ -0,0 +1,145 @@
+#![allow(clippy::crate_in_macro_def)]
+
+use std::error::Error;
+use std::fmt::Debug;
+use std::process::exit;
+
+/// This enum represents all possible errors that can occur in this crate.
+/// It is used as a return type for most functions should they return an error.
+/// There's 2 base variants: `Message` and `WithError`.
+/// `Message` is used for simple errors that don't have an underlying cause.
+/// `WithError` is used for errors that occur from another error.
+#[derive(thiserror::Error, Debug)]
+pub enum WinappsError {
+    #[error("{0}")]
+    Message(String),
+    #[error("{0}\n{1}")]
+    WithError(#[source] anyhow::Error, String),
+}
+
+impl WinappsError {
+    /// This function prints the error to the console.
+    /// It is used internally by the `unrecoverable` and `panic` functions.
+    /// All lines are logged as seperate messages, and the source of the error is also logged if it exists.
+    fn error(&self) {
+        let messages: Vec<String> = self.to_string().split('\n').map(|s| s.into()).collect();
+        messages.iter().for_each(|s| tracing::error!("{}", s));
+
+        if self.source().is_some() {
+            tracing::error!("Caused by: {}", self.source().unwrap());
+        }
+    }
+
+    /// This function prints the error to the console and exits the program with an exit code of 1.
+    pub fn unrecoverable(&self) -> ! {
+        self.error();
+
+        tracing::error!("Unrecoverable error, exiting...");
+        exit(1);
+    }
+
+    /// This function prints the error to the console and panics.
+    pub fn panic(&self) -> ! {
+        self.error();
+
+        panic!("Program crashed, see log above");
+    }
+}
+
+/// This macro is a shortcut for creating a `WinappsError` from a string.
+/// You can use normal `format!` syntax inside the macro.
+#[macro_export]
+macro_rules! error {
+    ($($fmt:tt)*) => {
+       crate::errors::WinappsError::Message(format!($($fmt)*))
+    };
+}
+
+/// This macro is a shortcut for creating a `WinappsError` from a string.
+/// The first argument is the source error.
+/// You can use normal `format!` syntax inside the macro.
+#[macro_export]
+macro_rules! error_from {
+    ($err:expr, $($fmt:tt)*) => {
+       crate::errors::WinappsError::WithError(anyhow::Error::new($err), format!($($fmt)*))
+    };
+}
+
+/// This trait serves as a generic way to convert a `Result` or `Option` into a `WinappsError`.
+pub trait IntoError<T> {
+    fn into_error(self, msg: String) -> Result<T, WinappsError>;
+}
+
+impl<T, U> IntoError<T> for Result<T, U>
+where
+    T: Debug,
+    U: Error + Send + Sync + 'static,
+{
+    fn into_error(self, msg: String) -> Result<T, WinappsError> {
+        if let Err(error) = self {
+            return Err(WinappsError::WithError(anyhow::Error::new(error), msg));
+        }
+
+        Ok(self.unwrap())
+    }
+}
+
+impl<T> IntoError<T> for Option<T> {
+    fn into_error(self, msg: String) -> Result<T, WinappsError> {
+        if self.is_none() {
+            return Err(WinappsError::Message(msg));
+        }
+
+        Ok(self.unwrap())
+    }
+}
+
+/// This function unwraps a `Result` or `Option` and returns the value if it exists.
+/// Should the value not exist, then the program will exit with an exit code of 1.
+/// Called internally by the `unwrap_or_exit!` macro, which you should probably use instead.
+pub fn unwrap_or_exit<T, U>(val: U, msg: String) -> T
+where
+    T: Sized + Debug,
+    U: IntoError<T>,
+{
+    val.into_error(msg).unwrap_or_else(|e| e.unrecoverable())
+}
+
+/// This function unwraps a `Result` or `Option` and returns the value if it exists.
+/// Should the value not exist, then the program will panic.
+/// Called internally by the `unwrap_or_panic!` macro, which you should probably use instead.
+pub fn unwrap_or_panic<T, U>(val: U, msg: String) -> T
+where
+    T: Sized + Debug,
+    U: IntoError<T>,
+{
+    val.into_error(msg).unwrap_or_else(|e| e.panic())
+}
+
+/// This macro unwraps a `Result` or `Option` and returns the value if it exists.
+/// Should the value not exist, then the program will exit with exit code 1.
+/// Optionally, a message can be passed to the function which uses standard `format!` syntax.
+/// The result type has to implement `Debug` and `Sized`, and the error type has to implement `Error`, `Send`, `Sync` has to be `'static`.
+#[macro_export]
+macro_rules! unwrap_or_exit {
+    ($expr:expr) => {{
+        crate::errors::unwrap_or_exit($expr, "Expected a value, got None / Error".into())
+    }};
+    ($expr:expr, $($fmt:tt)*) => {{
+        crate::errors::unwrap_or_exit($expr, format!($($fmt)*))
+    }};
+}
+
+/// This macro unwraps a `Result` or `Option` and returns the value if it exists.
+/// Should the value not exist, then the program will panic.
+/// Optionally, a message can be passed to the function which uses standard `format!` syntax.
+/// The result type has to implement `Debug` and `Sized`, and the error type has to implement `Error`, `Send`, `Sync` has to be `'static`.
+#[macro_export]
+macro_rules! unwrap_or_panic {
+    ($expr:expr) => {{
+        crate::errors::unwrap_or_panic($expr, "Expected a value, got None / Error".into())
+    }};
+    ($expr:expr, $($fmt:tt)*) => {{
+        crate::errors::unwrap_or_panic($expr, format!($($fmt)*))
+    }};
+}

winapps/src/lib.rs

@@ -1,5 +1,8 @@
+pub mod errors;
+pub mod freerdp;
 pub mod quickemu;
 
+use crate::errors::WinappsError;
 use derive_new::new;
 use home::home_dir;
 use serde::{Deserialize, Serialize};
@@ -10,8 +13,7 @@ use std::{
     fs::{self, File},
     path::Path,
 };
-
-pub mod freerdp;
+use tracing::{info, warn};
 
 pub trait RemoteClient {
     fn check_depends(&self, config: Config);
@@ -59,22 +61,24 @@ pub fn get_config_file(path: Option<&str>) -> PathBuf {
     let default = match env::var("XDG_CONFIG_HOME") {
         Ok(dir) => PathBuf::from(dir).join("winapps"),
         Err(_) => {
-            println!("Couldn't read XDG_CONFIG_HOME, falling back to ~/.config");
-            home_dir()
-                .expect("Could not find the home path!")
-                .join(".config/winapps")
+            warn!("Couldn't read XDG_CONFIG_HOME, falling back to ~/.config");
+            unwrap_or_panic!(home_dir(), "Couldn't find the home directory").join(".config/winapps")
         }
     };
 
-    let path = Path::new(path.unwrap_or(default.to_str().unwrap()));
+    let path = Path::new(path.unwrap_or(unwrap_or_panic!(
+        default.to_str(),
+        "Couldn't convert path {:?} to string",
+        default
+    )));
 
     if !path.exists() {
-        println!("{:?} does not exist! Creating...", path);
+        info!("{:?} does not exist! Creating...", path);
         fs::create_dir_all(path).expect("Failed to create directory");
     }
 
     if !path.is_dir() {
-        panic!("Config directory {:?} is not a directory!", path);
+        error!("Config directory {:?} is not a directory", path).panic();
     }
 
     path.join("config.toml")
@@ -85,54 +89,76 @@ pub fn load_config(path: Option<&str>) -> Config {
     let config_path = get_config_file(path);
 
     if !config_path.exists() {
-        save_config(&config, path).expect("Failed to write default configuration");
+        unwrap_or_panic!(
+            save_config(&config, path),
+            "Failed to write default configuration"
+        );
+
         return config;
     }
 
-    let config_file = fs::read_to_string(config_path).expect("Failed to read configuration file");
-    let config: Config =
-        toml::from_str(config_file.as_str()).expect("Failed to parse the configuration");
+    let config_file = unwrap_or_panic!(
+        fs::read_to_string(config_path),
+        "Failed to read configuration file"
+    );
+
+    let config: Config = unwrap_or_panic!(
+        toml::from_str(config_file.as_str()),
+        "Failed to parse configuration file",
+    );
 
     config
 }
 
-pub fn save_config(config: &Config, path: Option<&str>) -> std::io::Result<()> {
+pub fn save_config(config: &Config, path: Option<&str>) -> Result<(), WinappsError> {
     let config_path = get_config_file(path);
-    let serialized_config = toml::to_string(&config).expect("Failed to serialize configuration");
+    let serialized_config = unwrap_or_panic!(
+        toml::to_string(&config),
+        "Failed to serialize configuration"
+    );
 
     let mut config_file = match config_path.exists() {
-        true => File::open(&config_path).expect("Failed to open configuration file"),
-        false => File::create(&config_path).expect("Failed to create configuration file"),
+        true => unwrap_or_panic!(
+            File::open(&config_path),
+            "Failed to open configuration file"
+        ),
+        false => unwrap_or_panic!(
+            File::create(&config_path),
+            "Failed to create configuration file"
+        ),
     };
 
-    write!(config_file, "{}", serialized_config)
+    if let Err(e) = write!(config_file, "{}", serialized_config) {
+        return Err(error_from!(e, "Failed to write configuration file"));
+    }
+
+    Ok(())
 }
 
 pub fn get_data_dir() -> PathBuf {
-    let data_dir = match env::var("XDG_DATA_HOME") {
+    let path = match env::var("XDG_DATA_HOME") {
         Ok(dir) => PathBuf::from(dir).join("winapps"),
         Err(_) => {
-            println!("Couldn't read XDG_DATA_HOME, falling back to ~/.local/share");
-            home_dir()
-                .expect("Could not find the home path!")
+            warn!("Couldn't read XDG_DATA_HOME, falling back to ~/.local/share");
+            unwrap_or_panic!(home_dir(), "Couldn't find the home directory")
                 .join(".local/share/winapps")
         }
     };
 
-    if !data_dir.exists() {
-        let dir = data_dir.clone();
-        println!(
+    if !path.exists() {
+        let dir = path.clone();
+        info!(
             "Data directory {:?} does not exist! Creating...",
             dir.to_str()
         );
         fs::create_dir_all(dir).expect("Failed to create directory");
     }
 
-    if !data_dir.is_dir() {
-        panic!("Data directory {:?} is not a directory!", data_dir);
+    if !path.is_dir() {
+        error!("Data directory {:?} is not a directory", path).panic();
     }
 
-    data_dir
+    path
 }
 
 pub fn add(left: usize, right: usize) -> usize {