parse sensor json values

gleam.toml

@@ -22,6 +22,7 @@ spoke_mqtt_actor = ">= 1.1.1 and < 2.0.0"
 spoke_tcp = ">= 2.0.0 and < 3.0.0"
 gleam_erlang = ">= 1.3.0 and < 2.0.0"
 gleam_otp = ">= 1.2.0 and < 2.0.0"
+gleam_json = ">= 3.1.0 and < 4.0.0"
 
 [dev_dependencies]
 gleeunit = ">= 1.0.0 and < 2.0.0"

manifest.toml

@@ -8,6 +8,7 @@ packages = [
   { name = "filepath", version = "1.1.2", build_tools = ["gleam"], requirements = ["gleam_stdlib"], otp_app = "filepath", source = "hex", outer_checksum = "B06A9AF0BF10E51401D64B98E4B627F1D2E48C154967DA7AF4D0914780A6D40A" },
   { name = "glaml", version = "3.0.2", build_tools = ["gleam"], requirements = ["gleam_stdlib", "yamerl"], otp_app = "glaml", source = "hex", outer_checksum = "100CA23F526AB159712A3204D200969571FC43B193736B320C1400D410DEE7AD" },
   { name = "gleam_erlang", version = "1.3.0", build_tools = ["gleam"], requirements = ["gleam_stdlib"], otp_app = "gleam_erlang", source = "hex", outer_checksum = "1124AD3AA21143E5AF0FC5CF3D9529F6DB8CA03E43A55711B60B6B7B3874375C" },
+  { name = "gleam_json", version = "3.1.0", build_tools = ["gleam"], requirements = ["gleam_stdlib"], otp_app = "gleam_json", source = "hex", outer_checksum = "44FDAA8847BE8FC48CA7A1C089706BD54BADCC4C45B237A992EDDF9F2CDB2836" },
   { name = "gleam_otp", version = "1.2.0", build_tools = ["gleam"], requirements = ["gleam_erlang", "gleam_stdlib"], otp_app = "gleam_otp", source = "hex", outer_checksum = "BA6A294E295E428EC1562DC1C11EA7530DCB981E8359134BEABC8493B7B2258E" },
   { name = "gleam_stdlib", version = "0.70.0", build_tools = ["gleam"], requirements = [], otp_app = "gleam_stdlib", source = "hex", outer_checksum = "86949BF5D1F0E4AC0AB5B06F235D8A5CC11A2DFC33BF22F752156ED61CA7D0FF" },
   { name = "gleeunit", version = "1.9.0", build_tools = ["gleam"], requirements = ["gleam_stdlib"], otp_app = "gleeunit", source = "hex", outer_checksum = "DA9553CE58B67924B3C631F96FE3370C49EB6D6DC6B384EC4862CC4AAA718F3C" },
@@ -25,6 +26,7 @@ packages = [
 envoy = { version = ">= 1.1.0 and < 2.0.0" }
 glaml = { version = ">= 3.0.2 and < 4.0.0" }
 gleam_erlang = { version = ">= 1.3.0 and < 2.0.0" }
+gleam_json = { version = ">= 3.1.0 and < 4.0.0" }
 gleam_otp = { version = ">= 1.2.0 and < 2.0.0" }
 gleam_stdlib = { version = ">= 0.44.0 and < 2.0.0" }
 gleeunit = { version = ">= 1.0.0 and < 2.0.0" }

src/config.gleam

@@ -1,9 +1,5 @@
 import envoy
 import glaml
-import gleam/dict
-import gleam/erlang/node
-import gleam/io
-import gleam/list
 import gleam/option.{type Option, None, Some}
 import gleam/result
 import simplifile

src/readings_broadcaster.gleam

@@ -1,5 +1,5 @@
+import gleam/bit_array
 import gleam/erlang/process
-import gleam/io
 import gleam/list
 import gleam/otp/actor
 import sensors
@@ -17,11 +17,13 @@ fn handle_message(
   state: State,
   update: mqtt.Update,
 ) -> actor.Next(State, mqtt.Update) {
+  echo update
   case parse_mqtt_update(update) {
-    Ok(reading) -> {
+    Ok(readings) -> {
       // Publish to all subscribers
+      echo readings
       list.each(state.subscribers, fn(subscriber) {
-        process.send(subscriber, reading)
+        list.each(readings, fn(reading) { process.send(subscriber, reading) })
       })
       actor.continue(state)
     }
@@ -29,12 +31,20 @@ fn handle_message(
   }
 }
 
-fn parse_mqtt_update(update: mqtt.Update) -> Result(sensors.SensorReading, Nil) {
-  io.println("GOT MQTT MESSAGE!")
-  echo update
-  // TODO: Implement parsing logic based on your MQTT topic/payload structure
-  // For now, return an error
-  Error(Nil)
+fn parse_mqtt_update(
+  update: mqtt.Update,
+) -> Result(List(sensors.SensorReading), Nil) {
+  case update {
+    mqtt.ReceivedMessage(topic, payload, _) -> {
+      let assert Ok(payload_str) = bit_array.to_string(payload)
+      case topic {
+        "homeassistant/sensor/bws/node1/state1" ->
+          Ok(sensors.parse_topic_1(payload_str))
+        _ -> Error(Nil)
+      }
+    }
+    _ -> Error(Nil)
+  }
 }
 
 pub fn start(

src/sensors.gleam

@@ -1,5 +1,7 @@
+import gleam/dynamic/decode
 import gleam/float
 import gleam/io
+import gleam/json
 
 pub type Sensor {
   Temperature
@@ -25,7 +27,28 @@ pub fn sensor_name(sensor: Sensor) -> String {
   }
 }
 
-// homeassistant/sensor/bws/node1/state1
+pub const topic_1: String = "homeassistant/sensor/bws/node1/state1"
+
+type Topic1Value {
+  Topic1Value(temp: Float, humidity: Float, pressure: Float)
+}
+
+/// Parses a JSON string into a list of `SensorReading` values.
+/// example input string: {"temp":18.84,"humidity":28.690811,"pressure":944.67}
+pub fn parse_topic_1(json_string: String) -> List(SensorReading) {
+  let decoder = {
+    use temp <- decode.field("temp", decode.float)
+    use humidity <- decode.field("humidity", decode.float)
+    use pressure <- decode.field("pressure", decode.float)
+    decode.success(Topic1Value(temp:, humidity:, pressure:))
+  }
+  let assert Ok(decoded_val) = json.parse(from: json_string, using: decoder)
+  [
+    SensorReading(sensor: Temperature, value: decoded_val.temp),
+    SensorReading(sensor: Humidity, value: decoded_val.humidity),
+    SensorReading(sensor: Pressure, value: decoded_val.pressure),
+  ]
+}
 
 pub fn print_sensor_reading(reading: SensorReading) -> Nil {
   let sensor_name = sensor_name(reading.sensor)