Add error handling

Cargo.toml

@@ -13,6 +13,8 @@ ruuvi-sensor-protocol = "0.4.1"
 structopt = { version = "0.3", features = [ "paw" ] }
 paw = "1.0"
 colored = "1.9"
+failure = "0.1.7"
+exitfailure = "0.5.1"
 
 [[bin]]
 name = "ruuvi-cli"

src/bin/cli.rs

@@ -1,4 +1,6 @@
 use btleplug::api::{BDAddr, Central, ParseBDAddrError};
+use exitfailure::ExitFailure;
+use failure::ResultExt;
 use ruuvitag_sensor_rs::ble::{get_central, register_event_handler};
 use ruuvitag_sensor_rs::controller::Controller;
 use std::str::FromStr;
@@ -42,21 +44,26 @@ enum Args {
 }
 
 #[paw::main]
-fn main(args: Args) -> Result<(), std::io::Error> {
+fn main(args: Args) -> Result<(), ExitFailure> {
     let (controller, event_tx) = Controller::new();
 
-    let central = get_central();
+    let central =
+        get_central().with_context(|_| "could not initialize bluetooth adapter".to_string())?;
+
     central.active(false);
     register_event_handler(event_tx, &central);
 
+    central
+        .start_scan()
+        .with_context(|_| "could not start bluetooth scan".to_string())?;
+
     match args {
         Args::Collect {
             ruuvitags_macs,
             influxdb_url,
             influxdb_db_name,
             influxdb_measurement_name,
         } => {
-            central.start_scan().unwrap();
             controller.collect(
                 &ruuvitags_macs,
                 &influxdb_url,
@@ -65,11 +72,9 @@ fn main(args: Args) -> Result<(), std::io::Error> {
             );
         }
         Args::Find {} => {
-            central.start_scan().unwrap();
             controller.find();
         }
         Args::Show {} => {
-            central.start_scan().unwrap();
             controller.show();
         }
     }

src/ble.rs

@@ -1,22 +1,24 @@
 use crate::ruuvitag::{is_ruuvitag, RuuviTag};
-use btleplug::api::{
-    Central,
-    CentralEvent::{DeviceDiscovered, DeviceUpdated},
-    Peripheral,
+use btleplug::{
+    api::{
+        Central,
+        CentralEvent::{DeviceDiscovered, DeviceUpdated},
+        Peripheral,
+    },
+    bluez::{adapter::ConnectedAdapter, manager::Manager},
 };
-use btleplug::bluez::{adapter::ConnectedAdapter, manager::Manager};
 use std::sync::mpsc::Sender;
 
-pub fn get_central() -> ConnectedAdapter {
-    let manager = Manager::new().unwrap();
-    let adapters = manager.adapters().unwrap();
+pub fn get_central() -> Result<ConnectedAdapter, btleplug::Error> {
+    let manager = Manager::new()?;
+    let adapters = manager.adapters()?;
     let mut adapter = adapters.into_iter().next().unwrap();
 
     // reset the adapter -- clears out any errant state
-    adapter = manager.down(&adapter).unwrap();
-    adapter = manager.up(&adapter).unwrap();
+    adapter = manager.down(&adapter)?;
+    adapter = manager.up(&adapter)?;
 
-    adapter.connect().unwrap()
+    Ok(adapter.connect()?)
 }
 
 pub enum Event {