Add DeviceId from str conversion

bluez-async/src/device.rs

@@ -3,6 +3,7 @@ use dbus::Path;
 use dbus::arg::{PropMap, RefArg, Variant, cast};
 use serde::{Deserialize, Serialize};
 use std::collections::HashMap;
+use std::convert::TryFrom;
 use std::fmt::{self, Display, Formatter};
 use std::str::FromStr;
 use uuid::Uuid;
@@ -41,6 +42,23 @@ impl From<DeviceId> for Path<'static> {
     }
 }
 
+impl FromStr for DeviceId {
+    type Err = BluetoothError;
+
+    fn from_str(s: &str) -> Result<Self, Self::Err> {
+        if !s.starts_with("hci") {
+            return Err(BluetoothError::DeviceIdParseError(s.to_string()));
+        }
+
+        let path = Path::new(format!("/org/bluez/{}", s))
+            .map_err(|_| BluetoothError::DeviceIdParseError(s.to_string()))?;
+
+        Ok(DeviceId {
+            object_path: path.into_static(),
+        })
+    }
+}
+
 impl Display for DeviceId {
     fn fmt(&self, f: &mut Formatter<'_>) -> fmt::Result {
         write!(
@@ -296,6 +314,18 @@ mod tests {
         assert_eq!(device_id.to_string(), "hci0/dev_11_22_33_44_55_66");
     }
 
+    #[test]
+    fn from_string() {
+        let device_id = DeviceId::from_str("hci0/dev_11_22_33_44_55_66");
+        assert_eq!(device_id.unwrap().to_string(), "hci0/dev_11_22_33_44_55_66");
+
+        let invalid_id = DeviceId::from_str("dev_11_22_33_44_55_66");
+        assert_eq!(
+            invalid_id.unwrap_err().to_string(),
+            "Error parsing DeviceId string: dev_11_22_33_44_55_66"
+        );
+    }
+
     #[test]
     fn service_data() {
         let uuid = uuid_from_u32(0x11223344);

bluez-async/src/lib.rs

@@ -96,6 +96,9 @@ pub enum BluetoothError {
     /// Error parsing a `Modalias` from a string.
     #[error(transparent)]
     ModaliasParseError(#[from] ParseModaliasError),
+    /// Error parsing DeviceId from a string.
+    #[error("Error parsing DeviceId string: {0}")]
+    DeviceIdParseError(String),
 }
 
 /// Error type for futures representing tasks spawned by this crate.