From 224739a7ec9c430972b7d7f760e605fda084f28f Mon Sep 17 00:00:00 2001
From: Artemis Tosini <me@artem.ist>
Date: Sun, 31 May 2020 02:48:45 +0000
Subject: [PATCH] Add load, remove unwraps, fix high CPU

---
 src/main.rs       | 21 +++++++++++------
 src/tile.rs       |  2 +-
 src/tiles/load.rs | 60 +++++++++++++++++++++++++++++++++++++++++++++++
 src/tiles/mod.rs  |  2 ++
 src/tiles/time.rs | 10 ++++----
 5 files changed, 81 insertions(+), 14 deletions(-)
 create mode 100644 src/tiles/load.rs

diff --git a/src/main.rs b/src/main.rs
index 8a817d9..ae29dc4 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -5,7 +5,6 @@ pub mod tiles;
 use dbus_tokio::connection::new_session_sync;
 use std::sync::Arc;
 use tile::Tile;
-use tokio;
 use tokio::sync::mpsc::channel;
 use uuid::Uuid;
 
@@ -22,17 +21,25 @@ async fn main() -> Result<(), Box<dyn std::error::Error>> {
 
     let (sender, receiver) = channel(1024);
 
-    let instance = Uuid::new_v4().to_string().into_boxed_str();
-    let tiles: Vec<Arc<dyn Tile>> = vec![Arc::new(tiles::Time::new(0, sender, instance))];
+    let tiles: Vec<Arc<dyn Tile>> = vec![
+        Arc::new(tiles::Load::new(
+            0,
+            sender.clone(),
+            Uuid::new_v4().to_string().into_boxed_str(),
+        )),
+        Arc::new(tiles::Time::new(
+            1,
+            sender,
+            Uuid::new_v4().to_string().into_boxed_str(),
+        )),
+    ];
 
     for tile in &tiles {
         tile.clone().spawn();
     }
 
     let num_tiles = tiles.len();
-    tokio::spawn(async move {
-        output::launch(num_tiles, receiver).await.unwrap();
-    });
+    output::launch(num_tiles, receiver).await?;
 
-    loop {}
+    Ok(())
 }
diff --git a/src/tile.rs b/src/tile.rs
index 18d2ad0..e604365 100644
--- a/src/tile.rs
+++ b/src/tile.rs
@@ -71,5 +71,5 @@ pub struct TileData {
 }
 
 pub trait Tile: Send {
-    fn spawn(self: Arc<Self>) -> JoinHandle<()>;
+    fn spawn(self: Arc<Self>) -> JoinHandle<Result<(), Box<dyn std::error::Error + Send + Sync>>>;
 }
diff --git a/src/tiles/load.rs b/src/tiles/load.rs
new file mode 100644
index 0000000..b972b60
--- /dev/null
+++ b/src/tiles/load.rs
@@ -0,0 +1,60 @@
+use crate::tile::{Block, Tile, TileData};
+use async_std::sync::RwLock;
+use std::fs::File;
+use std::io::Read;
+use std::sync::Arc;
+use std::time::Duration;
+use tokio::sync::mpsc::{error::SendError, Sender};
+use tokio::task::JoinHandle;
+use tokio::time::interval;
+
+pub struct Load {
+    sender_id: usize,
+    sender: RwLock<Sender<TileData>>,
+    instance: Box<str>,
+}
+
+impl Load {
+    pub fn new(sender_id: usize, sender: Sender<TileData>, instance: Box<str>) -> Load {
+        Load {
+            sender_id,
+            sender: RwLock::new(sender),
+            instance,
+        }
+    }
+
+    async fn send(&self, data: TileData) -> Result<(), SendError<TileData>> {
+        let mut sender = self.sender.write().await;
+        sender.send(data).await
+    }
+
+    async fn run(&self) -> Result<(), Box<dyn std::error::Error + Send + Sync>> {
+        let mut timer = interval(Duration::from_secs(5));
+        let mut raw = String::new();
+        loop {
+            timer.tick().await;
+            File::open("/proc/loadavg")?.read_to_string(&mut raw)?;
+            let (load, _rest) = raw.split_at(raw.find(' ').unwrap_or(0));
+            let block = Block {
+                full_text: load.into(),
+                instance: self.instance.clone(),
+                name: "load".into(),
+                ..Default::default()
+            };
+            let data = TileData {
+                block,
+                sender_id: self.sender_id,
+            };
+            self.send(data).await?;
+        }
+    }
+}
+
+impl Tile for Load {
+    fn spawn(self: Arc<Self>) -> JoinHandle<Result<(), Box<dyn std::error::Error + Send + Sync>>> {
+        tokio::spawn(async move {
+            let instance = self;
+            instance.run().await
+        })
+    }
+}
diff --git a/src/tiles/mod.rs b/src/tiles/mod.rs
index 1ae628f..acafe19 100644
--- a/src/tiles/mod.rs
+++ b/src/tiles/mod.rs
@@ -1,2 +1,4 @@
+pub mod load;
 pub mod time;
+pub use load::Load;
 pub use time::Time;
diff --git a/src/tiles/time.rs b/src/tiles/time.rs
index 53f9a4b..3d12a24 100644
--- a/src/tiles/time.rs
+++ b/src/tiles/time.rs
@@ -47,10 +47,10 @@ impl Time {
         self.send(data).await
     }
 
-    async fn run(&self) {
+    async fn run(&self) -> Result<(), Box<dyn std::error::Error + Send + Sync>> {
         let mut time = Local::now();
         loop {
-            self.send_time(time).await.unwrap();
+            self.send_time(time).await?;
             time = Local::now();
             let millis_part = time.naive_local().timestamp_subsec_millis() as u64;
             let delay_ms = 1000u64 - millis_part % 1000; // Don't crash if we hit a leap second
@@ -60,12 +60,10 @@ impl Time {
 }
 
 impl Tile for Time {
-    fn spawn(self: Arc<Self>) -> JoinHandle<()> {
+    fn spawn(self: Arc<Self>) -> JoinHandle<Result<(), Box<dyn std::error::Error + Send + Sync>>> {
         tokio::spawn(async move {
             let instance = self;
-            loop {
-                instance.run().await
-            }
+            instance.run().await
         })
     }
 }