First attempt on SignalK Websocket handling

.gitignore

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+/target

src/signalk.rs

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+use std::thread;
+use tungstenite::connect;
+use url::Url;
+use serde_json::{Result, Value};
+
+// Model the data sent over SignalK Websocket
+// that I'm interested in
+pub enum SignalKEvent {
+  SpeedOverGround(f32),
+  SpeedThroughWater(f32),
+  Location(f32, f32),
+  CourseOverGround(f32),
+  TrueCompassCourse(f32),
+  AISVessel(String, f32, f32, f32), // Name, lat, long, speed
+  BatteryLevel(u8, u8),             // Bank#, percentage
+  FuelLevel(u8),                    // percentage
+}
+
+
+pub struct SignalKData {
+  latitude: f32,
+  longitude: f32,
+  position_timestamp: u64,
+}
+
+impl SignalKData {
+
+  pub fn parseJson (json: String) -> Vec<SignalKEvent> {
+    let res = Vec::<SignalKEvent>::new();
+    let v: Value = match serde_json::from_str(&json) {
+      Ok(value) => value,
+      Err(_) => return res,
+    };
+/*    for d in v["updates"]["values"] {
+      println!("{}", d);
+    } */
+    res
+  }
+
+  pub fn connect() -> SignalKData {
+    let mut data = SignalKData {
+      latitude: f32::NAN,
+      longitude: f32::NAN,
+      position_timestamp: 0,
+    };
+    let handle = thread::spawn(|| {
+      let (mut socket, response) = connect(Url::parse("ws://localhost:3000/signalk/v1/stream?subscribe=self").unwrap()).expect("Can't connect");
+      loop {
+        let msg = socket.read_message().expect("Error reading message");
+        if msg.is_text() {
+          println!("{}", msg.into_text().unwrap());
+        }
+      }
+    });
+    data
+  }
+
+}