[RFC] BREAKING CHANGES: A feature for every readout type (Closes #110)

Cargo.toml

@@ -12,22 +12,22 @@ build = "build.rs"
 
 [dependencies]
 cfg-if = "1.0.0"
-libc = "0.2.112"
-home = "0.5.3"
+libc = { version = "0.2.112", optional = true }
+home = { version = "0.5.3", optional = true }
 
 [target.'cfg(not(target_os = "windows"))'.dependencies]
-if-addrs = "0.7.0"
+if-addrs = { version = "0.7.0", optional = true }
 
 [target.'cfg(any(target_os="freebsd", target_os = "linux"))'.dependencies]
-sqlite = "0.26.0"
+sqlite = { version = "0.26.0", optional = true }
 
 [target.'cfg(any(target_os="freebsd", target_os = "netbsd"))'.dependencies]
-x11rb = "0.9.0"
+x11rb = { version = "0.9.0", optional = true }
 
 [target.'cfg(target_os = "linux")'.dependencies]
-dirs = "4.0"
-walkdir = "2.3.2"
-os-release = "0.1"
+dirs = { version = "4.0", optional = true }
+walkdir = { version = "2.3.2", optional = true }
+os-release = { version = "0.1", optional = true }
 
 [target.'cfg(target_os = "netbsd")'.dependencies]
 nix = "0.23.1"
@@ -39,7 +39,7 @@ core-graphics = "0.22.3"
 mach = "0.3.2"
 
 [target.'cfg(target_family = "unix")'.dependencies]
-num_cpus = "1.13.1"
+num_cpus = { version = "1.13.1", optional = true }
 
 [target.'cfg(target_os = "windows")'.dependencies]
 local-ip-address = "0.4.4"
@@ -54,10 +54,10 @@ windows = { version = "0.29.0", features = [
 wmi = "0.9.2"
 
 [target.'cfg(any(target_os = "linux", target_os = "netbsd", target_os = "android"))'.dependencies]
-itertools = "0.10.3"
+itertools = { version = "0.10.3", optional = true }
 
 [target.'cfg(not(any(target_os = "netbsd", target_os = "windows")))'.dependencies]
-sysctl = "0.4.3"
+sysctl = { version = "0.4.3", optional = true }
 
 [target.'cfg(any(target_os = "linux", target_os = "netbsd"))'.build-dependencies]
 pkg-config = { version = "0.3.24", optional = true}
@@ -69,5 +69,16 @@ default-features = false
 features = ["build","cargo","git","rustc"]
 
 [features]
+default = ["general", "kernel", "memory", "network", "package", "product", "graphical", "processor"]
+general = ["libc", "os-release", "x11rb", "dirs", "sysctl"]
+kernel  = ["libc", "sysctl"]
+memory  = []
+network = ["if-addrs"]
+package = ["sqlite", "walkdir", "home"]
+product = ["itertools"]
+battery = []
+processor = ["num_cpus", "libc"]
+graphical = ["libc", "dirs"]
+
 openwrt = []
-hash = ["vergen"]
+version = ["vergen", "pkg-config"]

src/android/mod.rs

@@ -17,6 +17,7 @@ impl From<std::str::Utf8Error> for ReadoutError {
         ReadoutError::Other(e.to_string())
     }
 }
+
 impl From<std::num::ParseFloatError> for ReadoutError {
     fn from(e: std::num::ParseFloatError) -> Self {
         ReadoutError::Other(e.to_string())
@@ -237,6 +238,7 @@ impl GeneralReadout for AndroidGeneralReadout {
                 }
             }
         }
+
         match (hardware, model, processor) {
             (Some(hardware), _, _) => Ok(hardware),
             (_, Some(model), _) => Ok(model),
@@ -436,7 +438,7 @@ impl AndroidPackageReadout {
         };
 
         let dpkg_dir = Path::new(&prefix).join("var/lib/dpkg/info");
-        
+
         extra::get_entries(&dpkg_dir).map(|entries| {
             entries
                 .iter()

src/enums.rs

@@ -0,0 +1,119 @@
+use std::fmt;
+
+/// This enum contains possible error types when doing sensor & variable readouts.
+#[derive(Debug, Clone)]
+pub enum ReadoutError {
+    /// A specific metric might not be available on all systems (e. g. battery percentage on a
+    /// desktop). \
+    /// If you encounter this error, it means that the requested value is not available.
+    MetricNotAvailable,
+
+    /// The default error for any readout that is not implemented by a particular platform.
+    NotImplemented,
+
+    /// A readout for a metric might be available, but fails due to missing dependencies or other
+    /// unsatisfied requirements.
+    Other(String),
+
+    /// Getting a readout on a specific operating system might not make sense or causes some other
+    /// kind of warning. This is not necessarily an error.
+    Warning(String),
+}
+
+impl ToString for ReadoutError {
+    fn to_string(&self) -> String {
+        match self {
+            ReadoutError::MetricNotAvailable => {
+                String::from("Metric is not available on this system.")
+            }
+            ReadoutError::NotImplemented => {
+                String::from("This metric is not available on this platform or is not yet implemented by libmacchina.")
+            }
+            ReadoutError::Other(s) => s.clone(),
+            ReadoutError::Warning(s) => s.clone(),
+        }
+    }
+}
+
+impl From<&ReadoutError> for ReadoutError {
+    fn from(r: &ReadoutError) -> Self {
+        r.to_owned()
+    }
+}
+
+/// Holds the possible variants for battery status.
+pub enum BatteryState {
+    Charging,
+    Discharging,
+}
+
+impl From<BatteryState> for &'static str {
+    fn from(state: BatteryState) -> &'static str {
+        match state {
+            BatteryState::Charging => "Charging",
+            BatteryState::Discharging => "Discharging",
+        }
+    }
+}
+
+/// The currently running shell is a program, whose path
+/// can be _relative_, or _absolute_.
+#[derive(Debug)]
+pub enum ShellFormat {
+    Relative,
+    Absolute,
+}
+
+#[derive(Debug)]
+/// There are two distinct kinds of shells, a so called *"current"* shell, i.e. the shell the user is currently using.
+/// And a default shell, i.e. that the user sets for themselves using the `chsh` tool.
+pub enum ShellKind {
+    Current,
+    Default,
+}
+
+#[derive(Debug)]
+/// The supported package managers whose packages can be extracted.
+pub enum PackageManager {
+    Homebrew,
+    MacPorts,
+    Pacman,
+    Portage,
+    Dpkg,
+    Opkg,
+    Xbps,
+    Pkgsrc,
+    Apk,
+    Eopkg,
+    Rpm,
+    Cargo,
+    Flatpak,
+    Snap,
+    Android,
+    Pkg,
+    Scoop,
+}
+
+impl fmt::Display for PackageManager {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        match *self {
+            PackageManager::Homebrew => write!(f, "homebrew"),
+            PackageManager::MacPorts => write!(f, "macports"),
+            PackageManager::Pacman => write!(f, "pacman"),
+            PackageManager::Portage => write!(f, "portage"),
+            PackageManager::Dpkg => write!(f, "dpkg"),
+            PackageManager::Opkg => write!(f, "opkg"),
+            PackageManager::Xbps => write!(f, "xbps"),
+            PackageManager::Pkgsrc => write!(f, "pkgsrc"),
+            PackageManager::Apk => write!(f, "apk"),
+            PackageManager::Eopkg => write!(f, "eopkg"),
+            PackageManager::Rpm => write!(f, "rpm"),
+            PackageManager::Cargo => write!(f, "cargo"),
+            PackageManager::Flatpak => write!(f, "flatpak"),
+            PackageManager::Snap => write!(f, "snap"),
+            PackageManager::Android => write!(f, "android"),
+            PackageManager::Pkg => write!(f, "pkg"),
+            PackageManager::Scoop => write!(f, "scoop"),
+        }
+    }
+}