add test to parse_topic_1

config.yml

@@ -3,4 +3,4 @@ mqtt:
   client_id: "weather_portal_dev"
   user: "homeassistant"
   # password comes from env
-jwt_key: apuOQZyML+8PixmVDP4nXU4M # loaded from env on prod
+jwt_secret: apuOQZyML+8PixmVDP4nXU4M # loaded from env on prod

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

@@ -1,5 +1,6 @@
 import envoy
 import glaml
+import gleam/option.{type Option, None, Some}
 import gleam/result
 import simplifile
 
@@ -9,7 +10,7 @@ pub type Config {
     mqtt_user: String,
     mqtt_pw: String,
     mqtt_client_id: String,
-    jwt_key: String,
+    jwt_secret: String,
   )
 }
 
@@ -30,71 +31,59 @@ fn parse_yaml(contents: String) -> Result(glaml.Document, String) {
   }
 }
 
-fn compile_config(doc: glaml.Document) -> Result(Config, String) {
-  let root = glaml.document_root(doc)
+fn get_config_value(
+  root: glaml.Node,
+  yaml_key: Option(String),
+  env_var: Option(String),
+) -> String {
+  let from_env = case env_var {
+    Some(var) -> envoy.get(var)
+    None -> Error(Nil)
+  }
 
-  // Extract values from YAML
-  use mqtt_host_result <- result.try(
-    glaml.select_sugar(root, "mqtt.host")
-    |> result.map_error(fn(_) { "mqtt.host not found in config.yml" }),
-  )
-  use mqtt_user_result <- result.try(
-    glaml.select_sugar(root, "mqtt.user")
-    |> result.map_error(fn(_) { "mqtt.user not found in config.yml" }),
-  )
-  use mqtt_client_id_result <- result.try(
-    glaml.select_sugar(root, "mqtt.client_id")
-    |> result.map_error(fn(_) { "mqtt.client_id not found in config.yml" }),
-  )
-  use jwt_key_result <- result.try(
-    glaml.select_sugar(root, "jwt_key")
-    |> result.map_error(fn(_) { "jwt_key not found in config.yml" }),
-  )
-
-  // Extract strings from nodes
-  case
-    mqtt_host_result,
-    mqtt_user_result,
-    jwt_key_result,
-    mqtt_client_id_result
-  {
-    glaml.NodeStr(host),
-      glaml.NodeStr(user),
-      glaml.NodeStr(key),
-      glaml.NodeStr(client_id)
-    -> {
-      let yaml_config =
-        Config(
-          mqtt_host: host,
-          mqtt_user: user,
-          mqtt_pw: "placeholder",
-          mqtt_client_id: client_id,
-          jwt_key: key,
-        )
-
-      // Override with env vars
-      let final_config =
-        Config(
-          mqtt_host: envoy.get("MQTT_HOST")
-            |> result.unwrap(yaml_config.mqtt_host),
-          mqtt_user: envoy.get("MQTT_USER")
-            |> result.unwrap(yaml_config.mqtt_user),
-          mqtt_pw: envoy.get("MQTT_PW")
-            |> result.unwrap(yaml_config.mqtt_pw),
-          mqtt_client_id: envoy.get("MQTT_CLIENT_ID")
-            |> result.unwrap(yaml_config.mqtt_client_id),
-          jwt_key: envoy.get("JWT_KEY")
-            |> result.unwrap(yaml_config.jwt_key),
-        )
-
-      Ok(final_config)
+  case from_env {
+    Ok(val) -> val
+    Error(_) -> {
+      // Fall back to YAML if env var not found
+      case yaml_key {
+        Some(key) -> {
+          let assert Ok(node) = glaml.select_sugar(root, key)
+          let assert glaml.NodeStr(str) = node
+          str
+        }
+        None -> {
+          panic as { "Config value not found in environment or YAML" }
+        }
+      }
     }
-    _, _, _, _ -> Error("Config values must be strings in config.yml")
   }
 }
 
-pub fn load_config() -> Result(Config, String) {
+fn compile_config(doc: glaml.Document) -> Config {
+  let root = glaml.document_root(doc)
+  let get = fn(yaml_key: option.Option(String), env_var: option.Option(String)) -> String {
+    get_config_value(root, yaml_key, env_var)
+  }
+
+  Config(
+    mqtt_host: get(Some("mqtt.host"), None),
+    mqtt_pw: get(None, Some("MQTT_PW")),
+    mqtt_user: get(Some("mqtt.user"), None),
+    jwt_secret: get(Some("jwt_secret"), Some("JWT_SECRET")),
+    mqtt_client_id: get(Some("mqtt.client_id"), Some("MQTT_CLIENT_ID")),
+  )
+}
+
+fn get_doc() -> Result(glaml.Document, String) {
   use file_content <- result.try(load_file())
   use doc <- result.try(parse_yaml(file_content))
-  compile_config(doc)
+  Ok(doc)
+}
+
+pub fn load_config() -> Config {
+  let doc = get_doc()
+  case doc {
+    Ok(doc) -> compile_config(doc)
+    Error(err) -> panic as { "fail to load config: " <> err }
+  }
 }

src/mqtt.gleam

@@ -0,0 +1,46 @@
+import config
+import gleam/erlang/process
+import gleam/option.{None, Some}
+import readings_broadcaster
+import spoke/mqtt
+import spoke/mqtt_actor
+import spoke/tcp
+
+pub fn start(cfg: config.Config) -> mqtt_actor.Client {
+  let client_id = cfg.mqtt_client_id
+  let password = <<cfg.mqtt_pw:utf8>>
+  let auth = mqtt.AuthDetails(username: cfg.mqtt_user, password: Some(password))
+  let transport = tcp.connector_with_defaults(cfg.mqtt_host)
+  let connection_options =
+    mqtt.ConnectOptions(
+      client_id: client_id,
+      authentication: Some(auth),
+      transport_options: transport,
+      keep_alive_seconds: 120,
+      server_timeout_ms: 15_000,
+    )
+  let assert Ok(started) =
+    mqtt_actor.build(connection_options) |> mqtt_actor.start(100)
+  let client = started.data
+
+  let start_up_checker = process.new_subject()
+  mqtt_actor.subscribe_to_updates(client, start_up_checker)
+  mqtt_actor.connect(client, True, None)
+  let assert Ok(mqtt.ConnectionStateChanged(mqtt.ConnectAccepted(_))) =
+    process.receive(start_up_checker, 15_000)
+
+  let assert Ok(broadcaster) = readings_broadcaster.start([])
+  mqtt_actor.subscribe_to_updates(client, broadcaster)
+
+  client
+}
+
+pub fn subscribe(client: mqtt_actor.Client, topic: String) {
+  mqtt_actor.subscribe(client, [
+    mqtt.SubscribeRequest(topic, mqtt.ExactlyOnce),
+  ])
+}
+
+pub fn disconnect(client: mqtt_actor.Client) {
+  mqtt_actor.disconnect(client)
+}

src/readings_broadcaster.gleam

@@ -0,0 +1,66 @@
+import gleam/bit_array
+import gleam/erlang/process
+import gleam/list
+import gleam/otp/actor
+import sensors
+import spoke/mqtt
+
+// pub type Message {
+//   MqttUpdate(update: mqtt.Update)
+// }
+
+type State {
+  State(subscribers: List(process.Subject(sensors.SensorReading)))
+}
+
+fn handle_message(
+  state: State,
+  update: mqtt.Update,
+) -> actor.Next(State, mqtt.Update) {
+  echo update
+  case parse_mqtt_update(update) {
+    Ok(readings) -> {
+      // Publish to all subscribers
+      echo readings
+      list.each(state.subscribers, fn(subscriber) {
+        list.each(readings, fn(reading) { process.send(subscriber, reading) })
+      })
+      actor.continue(state)
+    }
+    Error(_) -> actor.continue(state)
+  }
+}
+
+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(
+  subscribers: List(process.Subject(sensors.SensorReading)),
+) -> Result(process.Subject(mqtt.Update), actor.StartError) {
+  let initial_state = State(subscribers: subscribers)
+  let assert Ok(started) =
+    actor.new(initial_state)
+    |> actor.on_message(handle_message)
+    |> actor.start
+  Ok(started.data)
+}
+// pub fn subscribe(
+//   reader: process.Subject(Message),
+// ) -> process.Subject(sensors.SensorReading) {
+//   let mailbox = process.new_subject()
+//   process.send(reader, Subscribe(mailbox))
+//   mailbox
+// }

src/sensors.gleam

@@ -1,5 +1,7 @@
+import gleam/dynamic/decode
 import gleam/float
 import gleam/io
+import gleam/json
 
 pub type Sensor {
   Temperature
@@ -25,6 +27,29 @@ pub fn sensor_name(sensor: Sensor) -> String {
   }
 }
 
+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)
   io.println(sensor_name <> ": " <> float.to_string(reading.value))

src/weather_portal.gleam

@@ -1,55 +1,18 @@
 import config
 import gleam/erlang/process
 import gleam/io
-import mqtt_dummy
-import sensors
+import mqtt
 
 pub fn main() -> Nil {
-  case config.load_config() {
-    Ok(cfg) -> {
-      io.println("Config loaded successfully!")
-      io.println("MQTT Host: " <> cfg.mqtt_host)
-      io.println("MQTT User: " <> cfg.mqtt_user)
-      io.println("MQTT PW: " <> cfg.mqtt_pw)
-      io.println("JWT Key: " <> cfg.jwt_key)
-    }
-    Error(err) -> {
-      io.println("Failed to load config: " <> err)
-    }
-  }
+  let cfg = config.load_config()
+  io.println("Config loaded successfully!")
 
-  let assert Ok(subject) = mqtt_dummy.start()
-  let mailbox = mqtt_dummy.subscribe(subject)
+  // Start MQTT, which will forward updates to sensor_reader
+  let client = mqtt.start(cfg)
+  let assert Ok(s) =
+    mqtt.subscribe(client, "homeassistant/sensor/bws/node1/state1")
+  echo s
 
-  // Kick off the first message
-  process.send_after(subject, 1000, mqtt_dummy.Proc)
-
-  receive_and_reschedule(mailbox, subject)
-  // case process.receive(mailbox, 5000) {
-  //   Ok(msg) -> {
-  //     io.println("Got message:" <> msg)
-  //     // process_messages(mailbox, n - 1)
-  //   }
-  //   Error(Nil) -> {
-  //     io.println("Timeout waiting for message")
-  //   }
-  // }
+  process.sleep_forever()
   Nil
 }
-
-fn receive_and_reschedule(
-  mailbox: process.Subject(sensors.SensorReading),
-  subject: process.Subject(mqtt_dummy.Message),
-) -> Nil {
-  case process.receive(mailbox, 2000) {
-    Ok(msg) -> {
-      sensors.print_sensor_reading(msg)
-      process.send_after(subject, 1000, mqtt_dummy.Proc)
-      receive_and_reschedule(mailbox, subject)
-    }
-    Error(Nil) -> {
-      io.println("Timeout - waiting again...")
-      receive_and_reschedule(mailbox, subject)
-    }
-  }
-}

test/config_test.gleam

@@ -1,4 +1,5 @@
 import config
+import envoy
 import gleeunit
 import gleeunit/should
 
@@ -8,7 +9,8 @@ pub fn main() -> Nil {
 
 // gleeunit test functions end in `_test`
 pub fn file_read_test() {
-  let assert Ok(cfg) = config.load_config()
+  envoy.set("MQTT_PW", "TEST")
+  let cfg = config.load_config()
 
   cfg.mqtt_host
   |> should.equal("192.168.1.11")

test/sensors_test.gleam

@@ -6,7 +6,6 @@ pub fn main() -> Nil {
   gleeunit.main()
 }
 
-// gleeunit test functions end in `_test`
 pub fn file_read_test() {
   let reading =
     sensors.sensor_name(sensors.Temperature)
@@ -17,3 +16,15 @@ pub fn file_read_test() {
   reading
   |> should.equal("Temperature 20.5 °C")
 }
+
+pub fn parse_topic_1_test() {
+  let json_string =
+    "{\"temp\":18.84,\"humidity\":28.690811,\"pressure\":944.67}"
+  let readings = sensors.parse_topic_1(json_string)
+  readings
+  |> should.equal([
+    sensors.SensorReading(sensor: sensors.Temperature, value: 18.84),
+    sensors.SensorReading(sensor: sensors.Humidity, value: 28.690811),
+    sensors.SensorReading(sensor: sensors.Pressure, value: 944.67),
+  ])
+}