Added mechanism to skip updates in a module

* This is useful in modules where HTTP API calls are made. Updating them
  every second is expensive, network intensive and can cause rate limits
  to be hit
* Added get_name() function to modules for easier debug statements

src/bar_modules/bar_module_cpu.rs

@@ -116,6 +116,11 @@ impl UnibarModuleCpu {
 
 impl bar_modules::BarModuleActions for UnibarModuleCpu {
 
+    // --------------------
+    fn get_name(&self) -> String {
+        return "UnibarModuleCpu".to_string();
+    }
+
     // --------------------
     fn clear(&mut self) {
         self.cpu_times_sample_1 = CpuTimes::new();

src/bar_modules/bar_module_date.rs

@@ -20,6 +20,11 @@ impl UnibarModuleDate {
 
 impl bar_modules::BarModuleActions for UnibarModuleDate {
 
+    // --------------------
+    fn get_name(&self) -> String {
+        return "UnibarModuleDate".to_string();
+    }
+
     // --------------------
     fn clear(&mut self) {
         self.date_time = Local::now();

src/bar_modules/bar_module_memory.rs

@@ -25,6 +25,11 @@ impl UnibarModuleMemory {
 
 impl bar_modules::BarModuleActions for UnibarModuleMemory {
 
+    // --------------------
+    fn get_name(&self) -> String {
+        return "UnibarModuleMemory".to_string();
+    }
+
     // --------------------
     fn clear(&mut self) {
         self.meminfo_str = "".to_string();

src/bar_modules/bar_module_music.rs

@@ -25,6 +25,11 @@ impl UnibarModuleMusic {
 
 impl bar_modules::BarModuleActions for UnibarModuleMusic {
 
+    // --------------------
+    fn get_name(&self) -> String {
+        return "UnibarModuleMusic".to_string();
+    }
+
     // --------------------
     fn clear(&mut self) {
         self.current_stdout     = "".to_string();

src/bar_modules/bar_module_network.rs

@@ -26,6 +26,11 @@ impl UnibarModuleNetwork {
 
 impl bar_modules::BarModuleActions for UnibarModuleNetwork {
 
+    // --------------------
+    fn get_name(&self) -> String {
+        return "UnibarModuleNetwork".to_string();
+    }
+
     // --------------------
     fn clear(&mut self) {
         self.network_info = json!(serde_json::Value::Null);

src/bar_modules/bar_module_power.rs

@@ -38,6 +38,11 @@ impl UnibarModulePower {
 
 impl bar_modules::BarModuleActions for UnibarModulePower {
 
+    // --------------------
+    fn get_name(&self) -> String {
+        return "UnibarModulePower".to_string();
+    }
+
     // --------------------
     fn clear(&mut self) {
         self.power_info = PowerData::new();

src/bar_modules/bar_module_time.rs

@@ -23,6 +23,11 @@ impl UnibarModuleTime {
 
 impl bar_modules::BarModuleActions for UnibarModuleTime {
 
+    // --------------------
+    fn get_name(&self) -> String {
+        return "UnibarModuleTime".to_string();
+    }
+
     // --------------------
     fn clear(&mut self) {
         self.date_time = Local::now();

src/bar_modules/bar_module_weather.rs

@@ -5,12 +5,14 @@ use serde_json::Value;
 use regex::Regex;
 
 use crate::common;
+use crate::common::UpdateResult;
 use crate::bar_modules;
 
 #[derive(Clone)]
 pub struct UnibarModuleWeather {
     opts:           common::AppOptions,
     weather_info:   Value,
+    update_cnt:     u32,
 }
 
 impl UnibarModuleWeather {
@@ -20,6 +22,7 @@ impl UnibarModuleWeather {
         UnibarModuleWeather {
             opts: o,
             weather_info: json!(serde_json::Value::Null),
+            update_cnt: 0,
         }
     }
 
@@ -159,6 +162,23 @@ impl UnibarModuleWeather {
 
 impl bar_modules::BarModuleActions for UnibarModuleWeather {
 
+    // --------------------
+    fn get_name(&self) -> String {
+        return "UnibarModuleWeather".to_string();
+    }
+
+    // --------------------
+    // Weather update every 60 cycles
+    fn should_update(&mut self) -> UpdateResult {
+        if self.update_cnt == 0 {
+            self.update_cnt = 300;
+            return UpdateResult::Update;
+        } else {
+            self.update_cnt -= 1;
+            return UpdateResult::Skip;
+        }
+    }
+
     // --------------------
     fn clear(&mut self) {
         self.weather_info = json!(serde_json::Value::Null);

src/bar_modules/mod.rs

@@ -1,6 +1,11 @@
+use crate::common::UpdateResult;
+
 // --------------------
 /// All Bar modules must implement the actions
 pub trait BarModuleActions {
+    /// Return String with name of the module
+    fn get_name(&self) -> String;
+
     /// Do necessary clean up before starting new fetch
     fn clear(&mut self);
 
@@ -13,6 +18,12 @@ pub trait BarModuleActions {
     /// Return a Unicode icon to display before content in the bar.
     /// This icon may differ based on content of the data
     fn get_icon(&self) -> String;
+
+    /// Returns UpdateResult depending on whether the module
+    /// should be updated during the current update cycle
+    fn should_update(&mut self) -> UpdateResult {
+        return UpdateResult::Update;
+    }
 }
 
 pub trait BarModuleDebug {

src/common/mod.rs

@@ -18,6 +18,12 @@ impl fmt::Display for TemperatureUnits {
     }
 }
 
+#[derive(Debug,PartialEq,Eq,Copy,Clone)]
+pub enum UpdateResult {
+    Update,
+    Skip
+}
+
 // --------------------
 // Application options
 // --------------------
@@ -29,4 +35,5 @@ pub struct AppOptions {
     pub music_progress:     bool,
     pub debug:              bool,
     pub debug_modules:      bool,
+    pub debug_update:       bool,
 }

src/main.rs

@@ -2,6 +2,7 @@ use std::str;
 use std::thread;
 use std::time::Duration;
 use clap::Parser;
+use crate::common::UpdateResult;
 
 // Common utilities/types
 mod common;
@@ -17,7 +18,7 @@ mod bar_modules;
  suitable to use in a status bar")]
 struct CommandlineArgs {
     /// Update interval in seconds
-    #[arg(short = 'i', long, default_value = "5")]
+    #[arg(short = 'i', long, default_value = "1")]
     interval: u64,
 
     /// Name of the weather station
@@ -40,6 +41,11 @@ struct CommandlineArgs {
     /// but before output is printed
     #[arg(short = 'M', long)]
     debug_modules: bool,
+
+    /// Show module debug information after all modules are evaluated
+    /// but before output is printed
+    #[arg(short = 'U', long)]
+    debug_update: bool,
 }
 
 //
@@ -95,8 +101,17 @@ impl Unibar {
             //
             // Following generates ICON+CONTENT string for a module to be displayed
             // in the bar
-            md.clear();
-            md.generate_data();
+            match md.should_update() {
+                UpdateResult::Update => {
+                    md.clear();
+                    md.generate_data();
+                }
+                UpdateResult::Skip => {
+                    if self.opts.debug_update {
+                        println!("Skipping module {}", md.get_name());
+                    }
+                }
+            }
             mod_parts.push(md.get_icon());
             mod_parts.push(md.get_content());
 
@@ -162,6 +177,7 @@ fn main() {
             music_progress: cmd_args.music_progress,
             debug: cmd_args.debug,
             debug_modules: cmd_args.debug_modules,
+            debug_update: cmd_args.debug_update,
         },
         bar_modules_enabled: Vec::new(),
         debug_modules_done: false,