switch from channel api to iterator

this allows the api consumer to controll the threading

examples/listen.rs

@@ -7,9 +7,8 @@ fn main() -> Result<(), btleplug::Error> {
     let addr = BDAddr::from_str("00:1A:7D:DA:71:08").unwrap();
     let adapter = adapter_by_mac(addr)?;
 
-    let rx = listen(adapter)?;
+    for sensor in listen(adapter)? {
-    loop {
+        println!("{}: {:?}", sensor.mac, sensor.data);
-        let data = rx.recv().unwrap();
-        println!("{}: {:?}", data.mac, data.data);
     }
+    Ok(())
 }

src/lib.rs

@@ -5,8 +5,6 @@ use btleplug::bluez::manager::Manager;
 use num_enum::TryFromPrimitive;
 use std::collections::HashMap;
 use std::convert::TryFrom;
-use std::sync::mpsc::{channel, Receiver};
-use std::thread::spawn;
 
 #[derive(Clone, Debug)]
 pub struct Sensor {
@@ -37,9 +35,7 @@ impl SensorRawData {
 
 pub fn listen<P: Peripheral, A: Central<P> + 'static>(
     adapter: A,
-) -> Result<Receiver<Sensor>, btleplug::Error> {
+) -> Result<impl Iterator<Item = Sensor>, btleplug::Error> {
-    let (tx, rx) = channel();
-
     let mut sensors: HashMap<BDAddr, SensorRawData> = HashMap::new();
 
     let event_receiver = adapter.event_receiver().unwrap();
@@ -47,29 +43,31 @@ pub fn listen<P: Peripheral, A: Central<P> + 'static>(
     // start scanning for devices
     adapter.start_scan()?;
 
-    spawn(move || {
+    Ok(event_receiver
-        while let Ok(event) = event_receiver.recv() {
+        .into_iter()
-            match event {
+        .filter_map(|event| match event {
             CentralEvent::DeviceDiscovered(bd_addr) | CentralEvent::DeviceUpdated(bd_addr) => {
+                Some(bd_addr)
+            }
+            _ => None,
+        })
+        .flat_map(move |bd_addr| {
             let peripheral = adapter.peripheral(bd_addr).unwrap();
-                    for data in peripheral.properties().service_data.values() {
+            peripheral
-                        if let Ok(update) = parse_advertising_data(data.as_slice()) {
+                .properties()
+                .service_data
+                .into_iter()
+                .map(move |(_, data)| (bd_addr, data))
+        })
+        .filter_map(|(bd_addr, data)| Some((bd_addr, parse_advertising_data(&data).ok()?)))
+        .map(move |(bd_addr, update)| {
             let sensor_data = sensors.entry(bd_addr).or_default();
             sensor_data.update(update);
-                            tx.send(Sensor {
+            Sensor {
                 mac: bd_addr,
                 data: (*sensor_data).into(),
-                            })
-                            .unwrap();
             }
-                    }
+        }))
-                }
-                _ => {}
-            }
-        }
-    });
-
-    Ok(rx)
 }
 
 #[derive(Default, Clone, Debug)]