fear: change refresh interval with hotkeys #16

Author: vladkens

Cargo.lock

@@ -19,4 +19,5 @@ libc = "0.2.168"
 num-traits = "0.2.19"
 ratatui = { version = "0.29.0", features = ["serde"] }
 serde = { version = "1.0.216", features = ["derive"] }
+serde-inline-default = "0.2.3"
 serde_json = "1.0.133"

Cargo.toml

@@ -1,3 +1,4 @@
+use std::sync::{Arc, RwLock};
 use std::{io::stdout, time::Instant};
 use std::{sync::mpsc, time::Duration};
 
@@ -121,6 +122,8 @@ enum Event {
   Update(Metrics),
   ChangeColor,
   ChangeView,
+  IncInterval,
+  DecInterval,
   Tick,
   Quit,
 }
@@ -131,6 +134,9 @@ fn handle_key_event(key: &event::KeyEvent, tx: &mpsc::Sender<Event>) -> WithErro
     KeyCode::Char('c') if key.modifiers == KeyModifiers::CONTROL => Ok(tx.send(Event::Quit)?),
     KeyCode::Char('c') => Ok(tx.send(Event::ChangeColor)?),
     KeyCode::Char('v') => Ok(tx.send(Event::ChangeView)?),
+    KeyCode::Char('+') => Ok(tx.send(Event::IncInterval)?),
+    KeyCode::Char('=') => Ok(tx.send(Event::IncInterval)?), // fallback to press without shift
+    KeyCode::Char('-') => Ok(tx.send(Event::DecInterval)?),
     _ => Ok(()),
   }
 }
@@ -157,17 +163,16 @@ fn run_inputs_thread(tx: mpsc::Sender<Event>, tick: u64) {
   });
 }
 
-fn run_sampler_thread(tx: mpsc::Sender<Event>, interval: u64) {
-  let interval = interval.max(100).min(10000);
-
+fn run_sampler_thread(tx: mpsc::Sender<Event>, msec: Arc<RwLock<u32>>) {
   std::thread::spawn(move || {
     let mut sampler = Sampler::new().unwrap();
 
     // Send initial metrics
     tx.send(Event::Update(sampler.get_metrics(100).unwrap())).unwrap();
 
     loop {
-      tx.send(Event::Update(sampler.get_metrics(interval).unwrap())).unwrap();
+      let msec = *msec.read().unwrap();
+      tx.send(Event::Update(sampler.get_metrics(msec).unwrap())).unwrap();
     }
   });
 }
@@ -372,7 +377,7 @@ impl App {
     };
 
     let block = self.title_block(&label_l, &label_r);
-    let usage = " Press 'q' to quit, 'c' – color, 'v' – view ";
+    let usage = format!(" 'q' – quit, 'c' – color, 'v' – view | -/+ {}ms ", self.cfg.interval);
     let block = block.title_bottom(Line::from(usage).right_aligned());
     let iarea = block.inner(rows[1]);
     f.render_widget(block, rows[1]);
@@ -387,10 +392,14 @@ impl App {
     f.render_widget(self.get_power_block("ANE", &self.ane_power, 0.0), ha[2]);
   }
 
-  pub fn run_loop(&mut self, interval: u64) -> WithError<()> {
+  pub fn run_loop(&mut self, interval: Option<u32>) -> WithError<()> {
+    // use from arg if provided, otherwise use config restored value
+    self.cfg.interval = interval.unwrap_or(self.cfg.interval).max(100).min(10_000);
+    let msec = Arc::new(RwLock::new(self.cfg.interval));
+
     let (tx, rx) = mpsc::channel::<Event>();
     run_inputs_thread(tx.clone(), 250);
-    run_sampler_thread(tx.clone(), interval);
+    run_sampler_thread(tx.clone(), msec.clone());
 
     let mut term = enter_term();
 
@@ -402,6 +411,14 @@ impl App {
         Event::Update(data) => self.update_metrics(data),
         Event::ChangeColor => self.cfg.next_color(),
         Event::ChangeView => self.cfg.next_view_type(),
+        Event::IncInterval => {
+          self.cfg.inc_interval();
+          *msec.write().unwrap() = self.cfg.interval;
+        }
+        Event::DecInterval => {
+          self.cfg.dec_interval();
+          *msec.write().unwrap() = self.cfg.interval;
+        }
         _ => {}
       }
     }

src/app.rs

@@ -1,5 +1,6 @@
 use ratatui::style::Color;
 use serde::{Deserialize, Serialize};
+use serde_inline_default::serde_inline_default;
 
 const COLORS_OPTIONS: [Color; 7] =
   [Color::Green, Color::Yellow, Color::Red, Color::Blue, Color::Magenta, Color::Cyan, Color::Reset];
@@ -10,10 +11,23 @@ pub enum ViewType {
   Gauge,
 }
 
+#[serde_inline_default]
 #[derive(Debug, Serialize, Deserialize)]
 pub struct Config {
+  #[serde_inline_default(ViewType::Sparkline)]
   pub view_type: ViewType,
+
+  #[serde_inline_default(COLORS_OPTIONS[0])]
   pub color: Color,
+
+  #[serde_inline_default(1000)]
+  pub interval: u32,
+}
+
+impl Default for Config {
+  fn default() -> Self {
+    serde_json::from_str("{}").unwrap()
+  }
 }
 
 impl Config {
@@ -72,10 +86,16 @@ impl Config {
     };
     self.save();
   }
-}
 
-impl Default for Config {
-  fn default() -> Self {
-    Self { color: COLORS_OPTIONS[0], view_type: ViewType::Sparkline }
+  pub fn dec_interval(&mut self) {
+    let step = 250;
+    self.interval = ((self.interval.saturating_sub(step) + step - 1) / step * step).max(step);
+    self.save();
+  }
+
+  pub fn inc_interval(&mut self) {
+    let step = 250;
+    self.interval = (self.interval.saturating_add(step) / step * step).min(10_000);
+    self.save();
   }
 }

src/config.rs

@@ -5,7 +5,7 @@ mod metrics;
 mod sources;
 
 use app::App;
-use clap::{Parser, Subcommand};
+use clap::{parser::ValueSource, CommandFactory, Parser, Subcommand};
 use metrics::Sampler;
 use std::error::Error;
 
@@ -33,20 +33,19 @@ struct Cli {
 
   /// Update interval in milliseconds
   #[arg(short, long, default_value_t = 1000)]
-  interval: u64,
+  interval: u32,
 }
 
 fn main() -> Result<(), Box<dyn Error>> {
   let args = Cli::parse();
-  let msec = args.interval.max(100);
 
   match &args.command {
     Some(Commands::Pipe { samples }) => {
       let mut sampler = Sampler::new()?;
       let mut counter = 0u32;
 
       loop {
-        let doc = sampler.get_metrics(msec)?;
+        let doc = sampler.get_metrics(args.interval.max(100))?;
         let doc = serde_json::to_string(&doc)?;
         println!("{}", doc);
 
@@ -59,6 +58,13 @@ fn main() -> Result<(), Box<dyn Error>> {
     Some(Commands::Debug) => debug::print_debug()?,
     _ => {
       let mut app = App::new()?;
+
+      let matches = Cli::command().get_matches();
+      let msec = match matches.value_source("interval") {
+        Some(ValueSource::CommandLine) => Some(args.interval),
+        _ => None,
+      };
+
       app.run_loop(msec)?;
     }
   }

src/main.rs

@@ -216,13 +216,13 @@ impl Sampler {
     Ok(val)
   }
 
-  pub fn get_metrics(&mut self, duration: u64) -> WithError<Metrics> {
+  pub fn get_metrics(&mut self, duration: u32) -> WithError<Metrics> {
     let measures: usize = 4;
     let mut results: Vec<Metrics> = Vec::with_capacity(measures);
 
     // do several samples to smooth metrics
     // see: https://github.com/vladkens/macmon/issues/10
-    for (sample, dt) in self.ior.get_samples(duration, measures) {
+    for (sample, dt) in self.ior.get_samples(duration as u64, measures) {
       let mut ecpu_usages = Vec::new();
       let mut pcpu_usages = Vec::new();
       let mut rs = Metrics::default();