Better error handling

[With input from AI in VSCode]

Cargo.toml

@@ -14,3 +14,4 @@ chrono = "0.4.41"
 chrono-tz = "0.10.3"
 iana-time-zone = "0.1.63"
 clap = { version = "4.5.1", features = ["derive"] }
+thiserror = "1.0"

src/bar_modules/bar_module_weather.rs

@@ -3,11 +3,19 @@ use curl::easy::{Easy, List};
 use serde_json::json;
 use serde_json::Value;
 use regex::Regex;
+use thiserror::Error;
+use std::num::ParseFloatError;
 
 use crate::common;
 use crate::common::UpdateResult;
 use crate::bar_modules;
 
+/// Number of cycles between weather updates
+const UPDATE_INTERVAL: u32 = 300;
+
+/// Base URL for the National Weather Service API
+const WEATHER_API_BASE: &str = "https://api.weather.gov";
+
 #[derive(Clone)]
 pub struct UnibarModuleWeather {
     opts:           common::AppOptions,
@@ -15,7 +23,27 @@ pub struct UnibarModuleWeather {
     update_cnt:     u32,
 }
 
+#[derive(Debug, Error)]
+pub enum WeatherError {
+    #[error("Invalid temperature format: {0}")]
+    ParseError(String),
+    #[error("API response missing temperature field: {0}")]
+    ApiResponseStrErr(String),
+}
+
+impl From<ParseFloatError> for WeatherError {
+    fn from(err: ParseFloatError) -> Self {
+        WeatherError::ParseError(err.to_string())
+    }
+}
+
 impl UnibarModuleWeather {
+    const FAHRENHEIT_MULTIPLIER: f64 = 9.0 / 5.0;
+    const FAHRENHEIT_OFFSET: f64 = 32.0;
+
+    fn celsius_to_fahrenheit(celsius: f64) -> f64 {
+        celsius * Self::FAHRENHEIT_MULTIPLIER + Self::FAHRENHEIT_OFFSET
+    }
 
     // --------------------
     pub fn new(o :common::AppOptions) -> Self {
@@ -27,23 +55,27 @@ impl UnibarModuleWeather {
     }
 
     // --------------------
-    fn get_current_temperature(&self) -> f32 {
+    fn get_current_temperature(&self) -> Result<f64, WeatherError> {
-        let deg_c :f32;
+        let deg_c = match &self.weather_info {
-
+            serde_json::Value::Null => 0.0,
-        match self.weather_info {
-            serde_json::Value::Null => {
-                deg_c = 0.0;
-            }
             _ => {
-                deg_c = self.weather_info["features"][0]["properties"]["temperature"]["value"]
+                // Safely navigate the JSON structure
-                        .to_string().parse().unwrap();
+                self.weather_info
+                    .get("features")
+                    .and_then(|f| f.get(0))
+                    .and_then(|f| f.get("properties"))
+                    .and_then(|p| p.get("temperature"))
+                    .and_then(|t| t.get("value"))
+                    .and_then(|v| v.as_f64())
+                    .ok_or(WeatherError::ApiResponseStrErr("as_str likely failed".to_string()))?
+                    // .parse()?
             }
-        }
+        };
 
-        match self.opts.weather_units {
+        Ok(match self.opts.weather_units {
-            common::TemperatureUnits::Metric => return deg_c,
+            common::TemperatureUnits::Metric => deg_c,
-            common::TemperatureUnits::Imperial => return (deg_c * 9.0 / 5.0) + 32.0,
+            common::TemperatureUnits::Imperial => Self::celsius_to_fahrenheit(deg_c),
-        }
+        })
     }
 
     // --------------------
@@ -100,7 +132,8 @@ impl UnibarModuleWeather {
         let mut url_string  = Vec::new();
         let mut curl_ret    = Vec::new();
 
-        url_string.push("https://api.weather.gov/icons".to_owned());
+        url_string.push(WEATHER_API_BASE.to_owned());
+        url_string.push("/icons".to_owned());
 
         curl.url(url_string.concat().as_str()).unwrap();
         {
@@ -171,7 +204,7 @@ impl bar_modules::BarModuleActions for UnibarModuleWeather {
     // Weather update every 60 cycles
     fn should_update(&mut self) -> UpdateResult {
         if self.update_cnt == 0 {
-            self.update_cnt = 300;
+            self.update_cnt = UPDATE_INTERVAL;
             return UpdateResult::Update;
         } else {
             self.update_cnt -= 1;
@@ -192,7 +225,8 @@ impl bar_modules::BarModuleActions for UnibarModuleWeather {
         let mut curl_ret    = Vec::new();
         let mut curl_err    = false;
 
-        url_string.push("https://api.weather.gov/stations/".to_owned());
+        url_string.push(WEATHER_API_BASE.to_owned());
+        url_string.push("/stations/".to_owned());
         url_string.push(self.opts.weather_station.to_owned());
         url_string.push("/observations?limit=1".to_owned());
 
@@ -233,8 +267,8 @@ impl bar_modules::BarModuleActions for UnibarModuleWeather {
 
     // --------------------
     fn get_content(&self) -> String {
-        let temperature_value :f32 = self.get_current_temperature();
+        let temperature_value   :f64 = self.get_current_temperature().expect("Temperature query");
-        let temperature_unit :String = self.get_temperature_unit();
+        let temperature_unit    :String = self.get_temperature_unit();
         // let temperature_icon :String = self.get_icon(v.clone());
 
         return format!("{:.0}{}", temperature_value, temperature_unit);
@@ -251,6 +285,9 @@ impl bar_modules::BarModuleActions for UnibarModuleWeather {
                 // "icon": "https://api.weather.gov/icons/land/night/ovc?size=medium",
                 let re = Regex::new(r"(\w+)\?size").unwrap();
                 let json_val = self.weather_info["features"][0]["properties"]["icon"].to_string();
+                if self.opts.debug {
+                    println!("-----> weather_data - {:#?}", self.weather_info["features"][0]["properties"]);
+                }
                 match self.weather_info["features"][0]["properties"]["icon"] {
                     serde_json::Value::Null => {
                         return "⁈".to_string();

src/bar_modules/mod.rs

@@ -3,34 +3,34 @@ use crate::common::UpdateResult;
 // --------------------
 /// All Bar modules must implement the actions
 pub trait BarModuleActions {
-    /// Return String with name of the module
+    /// Returns the name of the module
     fn get_name(&self) -> String;
 
-    /// Do necessary clean up before starting new fetch
+    /// Cleans up any state before refreshing data
     fn clear(&mut self);
 
-    /// Do necessary processing to generate data for this bar module
+    /// Fetches and processes new data for the module
     fn generate_data(&mut self);
 
-    /// Return String content to be displayed in the bar
+    /// Returns the formatted content to display in the bar
     fn get_content(&self) -> String;
 
-    /// Return a Unicode icon to display before content in the bar.
+    /// Returns a Unicode icon representing the module's current state
-    /// This icon may differ based on content of the data
     fn get_icon(&self) -> String;
 
-    /// Returns UpdateResult depending on whether the module
+    /// Determines if the module should update its data
-    /// should be updated during the current update cycle
+    /// Default implementation always returns Update
     fn should_update(&mut self) -> UpdateResult {
         return UpdateResult::Update;
     }
 }
 
 pub trait BarModuleDebug {
-    /// Print debug information at the end
+    /// Prints debug information about the module
     fn post_debug(&self);
 }
 
+// Module declarations
 pub mod bar_module_weather;
 pub mod bar_module_music;
 pub mod bar_module_network;