Prototype working

Cargo.lock

@@ -2,6 +2,12 @@
 # It is not intended for manual editing.
 version = 3
 
+[[package]]
+name = "anyhow"
+version = "1.0.68"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "2cb2f989d18dd141ab8ae82f64d1a8cdd37e0840f73a406896cf5e99502fab61"
+
 [[package]]
 name = "autocfg"
 version = "1.1.0"
@@ -1056,7 +1062,10 @@ checksum = "9c8d87e72b64a3b4db28d11ce29237c246188f4f51057d65a7eab63b7987e423"
 name = "weather_exporter"
 version = "0.1.0"
 dependencies = [
+ "anyhow",
  "bme280",
+ "byteorder",
+ "embedded-hal",
  "linux-embedded-hal",
  "tokio",
  "warp",

Cargo.toml

@@ -9,5 +9,8 @@ description = "A Prometheus exporter for weather data."
 [dependencies]
 bme280 = "0.4.4"
 linux-embedded-hal = "0.4.0-alpha.2"
+embedded-hal = "1.0.0-alpha.7"
 tokio = { version = "1.23.0", features = ["macros", "rt"] }
 warp = "0.3.3"
+byteorder = "1.4.3"
+anyhow = "1.0.68"

src/main.rs

@@ -1,23 +1,110 @@
-use bme280;
-use linux_embedded_hal::{I2cdev, Delay};
-use std::thread;
-use std::time::Duration;
+use bme280::{self, Measurements};
+use linux_embedded_hal::{I2cdev, Delay, I2CError};
+use embedded_hal::i2c::blocking::I2c;
+use byteorder::{LittleEndian, ByteOrder};
+use std::sync::{Arc, Mutex};
+use anyhow::{Result, anyhow};
+use warp::Filter;
 
-fn main() {
+struct LightSensor {
+    addr:    u8,
+    reg:     u8,
+    bus: I2cdev,
+}
 
-    let loop_time = Duration::from_secs(5);
+impl LightSensor {
+    fn new(bus: I2cdev, addr: u8, port: u8) -> Self {
+        Self { bus, addr, reg: port + 0x10 }
+    }
 
-    let i2c = I2cdev::new("/dev/i2c-1")
-        .expect("Could not open i2c bus");
-
-    let mut sensor = bme280::i2c::BME280::new_primary(i2c);
-
-    sensor.init(&mut Delay).expect("Could not initialize BME280 sensor");
-
-    loop {
-        let baro = sensor.measure(&mut Delay).expect("Could not perform measurement");
-        println!("H {}%, P {} PA, T {}°C", baro.humidity, baro.pressure, baro.temperature);
-        thread::sleep(loop_time);        
+    fn measure(&mut self) -> Result<u16, I2CError> {
+        self.bus.write(self.addr, &[self.reg])?;
+        //thread::sleep(Duration::from_millis(10));
+        let mut buf = [0; 2];
+        self.bus.write_read(self.addr, &[self.reg], &mut buf[..])?;
+        Ok(LittleEndian::read_u16(&buf))
     }
 
 }
+
+struct Station {
+    light: LightSensor,
+    bme280: bme280::i2c::BME280<I2cdev>,
+}
+
+impl Station {
+    fn new() -> Result<Self> {
+
+        let i2c = I2cdev::new("/dev/i2c-1")
+            .map_err(|e| anyhow!("Could not open i2c bus: {}", e))?;
+
+        // TODO properly share the device across the two consumers. Probably need to implement I2cdev for RefCell<impl I2cdev> or something
+        // for now just open it twice :/
+        let i2c2 = I2cdev::new("/dev/i2c-1")
+            .map_err(|e| anyhow!("Could not open second i2c bus: {}", e))?;
+
+        let mut bme280 = bme280::i2c::BME280::new_primary(i2c);
+        bme280.init(&mut Delay).expect("Could not initialize BME280 sensor");
+
+        let light = LightSensor::new(i2c2, 0x08, 0x00);
+
+        Ok(Self { light, bme280 })
+    }
+
+    fn measure(&mut self) -> Result<(Measurements<I2CError>, u16)> {
+        let baro = self.bme280.measure(&mut Delay)
+            .map_err(|e| anyhow!("Cannot measure bme280: {:?}", e))?;
+        let lux = self.light.measure()
+            .map_err(|e| anyhow!("Cannot measure light: {:?}", e))?;
+        Ok((baro, lux))
+    }
+
+    pub fn scrape(&mut self) -> String {
+
+        let ( Measurements { temperature, pressure, humidity, .. }, lux) = match self.measure() {
+            Err(e) => {
+                return format!("# Error measuring: {:?}", e)
+            },
+            Ok(v) => v,
+        };
+
+        let lux = lux as f64 / 1000f64;
+
+        eprintln!("Scraped data: T={temperature}°C P={pressure}Pa H={humidity}% L={lux}");
+
+        format!(
+"# HELP weather_temperature_celsius Temperature in °C
+# TYPE weather_temperature_celsius gauge
+weather_temperature_celsius {temperature}
+# HELP weather_humidity_percent Humidity percentage
+# TYPE weather_humidity_percent gauge
+weather_humidity_percent {humidity}
+# HELP weather_pressure_pascals Atmospheric pressure in Pascals
+# TYPE weather_pressure_pascals gauge
+weather_pressure_pascals {pressure}
+# HELP weather_illumination_relative Relative illumination as a fraction of the maximum
+# TYPE weather_illumination_relative gauge
+weather_illumination_relative {lux}
+")
+
+    }
+
+}
+
+#[tokio::main(flavor="current_thread")]
+async fn main() -> Result<()> {
+
+    let home = format!("<html><body><h1>Weather Station v0.1</h1><ul><li><a href=\"https://git.xolus.net/max/weather_exporter\">source code</a></li><li><a href=\"/metrics\">metrics</a></li></ul></body></html>");
+    let home: &'static str = Box::leak(home.into_boxed_str());
+
+    let station = Station::new()?;
+    let station = Arc::new(Mutex::new(station));
+
+    let filter = warp::path!("metrics").map(move || station.lock().unwrap().scrape())
+             .or(warp::path!().map(move || { warp::reply::html(home) }));
+
+    eprintln!("Starting web server.");
+    Ok(warp::serve(filter).run(([0,0,0,0], 9073)).await)
+
+
+}