rework main signature + impl builder for optimizer

src/file.rs

@@ -195,7 +195,7 @@ pub struct Directory {
 impl Directory {
     pub fn from_path(path: &str) -> Result<Self, Box<dyn std::error::Error>> {
         if !std::path::Path::new(path).is_dir() {
-            return Err(format!("Directory path: {} must be a directory", path).into());
+            return Err(format!("directory path: {} must be a directory", path).into());
         }
 
         let mut nb_files = 0;

src/main.rs

@@ -1,3 +1,5 @@
+use std::process::exit;
+
 use clap::Parser;
 use env_logger::Env;
 
@@ -22,17 +24,29 @@ struct Args {
 }
 
 #[tokio::main]
-async fn main() -> Result<(), Box<dyn std::error::Error>> {
+async fn main() {
     env_logger::Builder::from_env(Env::default().default_filter_or("info")).init();
 
     let args = Args::parse();
-    let directory = Directory::from_path(&args.src)?;
+    let directory = match Directory::from_path(&args.src) {
+        Ok(d) => d,
+        Err(e) => {
+            log::error!(
+                "unable to load directory from path: {}, details: {}",
+                args.src,
+                e
+            );
+            exit(1);
+        }
+    };
 
-    let optimizer = ImgOptimizer::new(&args.dest, args.workers);
+    let optimizer = ImgOptimizer::builder(&args.dest, args.workers)
+        .with_progress()
+        .build();
     let file_group =
         directory.get_file_group(Some(FileImgMimetype::Jpeg), Some(FileSizeRange::Tiny));
 
-    let result = optimizer.optimize(&file_group).await?;
+    let result = optimizer.optimize(&file_group).await;
     let (optimized, percent, size) = result.stats();
 
     log::info!(
@@ -41,6 +55,4 @@ async fn main() -> Result<(), Box<dyn std::error::Error>> {
         percent,
         size
     );
-
-    Ok(())
 }

src/optimizer.rs

@@ -133,17 +133,49 @@ pub struct ImgOptimizer {
     queue: Arc<Queue<File>>,
     cancel_token: CancellationToken,
     tracker: TaskTracker,
+    progress: Arc<ProgressBar>,
 }
 
-impl ImgOptimizer {
+pub struct ImgOptimizerBuilder(ImgOptimizer);
+
+impl ImgOptimizerBuilder {
     pub fn new(dest_dir: &str, nb_workers: usize) -> Self {
-        ImgOptimizer {
+        ImgOptimizerBuilder(ImgOptimizer {
             dest_dir: dest_dir.to_string(),
             nb_workers,
             queue: Arc::new(Queue::new()),
             cancel_token: CancellationToken::new(),
             tracker: TaskTracker::new(),
+            progress: Arc::new(ProgressBar::hidden()),
+        })
+    }
+
+    pub fn with_progress(mut self) -> Self {
+        let pb = Arc::new(ProgressBar::new(0));
+
+        let tmpl_res =
+            ProgressStyle::default_bar().template("{msg} [{bar:40}] {pos}/{len} ({eta})");
+
+        if let Err(e) = tmpl_res {
+            log::error!("unable to set the progress bar, {}", e);
+            return self;
         }
+
+        let style = tmpl_res.unwrap().progress_chars("##-");
+        pb.set_style(style);
+
+        self.0.progress = pb;
+        self
+    }
+
+    pub fn build(self) -> ImgOptimizer {
+        self.0
+    }
+}
+
+impl ImgOptimizer {
+    pub fn builder(dest_dir: &str, nb_workers: usize) -> ImgOptimizerBuilder {
+        ImgOptimizerBuilder::new(dest_dir, nb_workers)
     }
 
     pub async fn stop(&self) {
@@ -151,10 +183,7 @@ impl ImgOptimizer {
         self.cancel_token.cancel();
     }
 
-    pub async fn optimize(
+    pub async fn optimize(&self, file_group: &FileGroup) -> OptimizerResult {
-        &self,
-        file_group: &FileGroup,
-    ) -> Result<OptimizerResult, Box<dyn std::error::Error>> {
         let start = std::time::Instant::now();
 
         let results = Arc::new(RwLock::new(FileGroup::new()));
@@ -164,19 +193,13 @@ impl ImgOptimizer {
             self.queue.enqueue(file).await;
         }
 
-        let pb = Arc::new(ProgressBar::new(file_group.len() as u64));
+        self.progress.set_message("optimizing...");
-        pb.set_style(
-            ProgressStyle::default_bar()
-                .template("{msg} [{bar:40}] {pos}/{len} ({eta})")?
-                .progress_chars("##-"),
-        );
-        pb.set_message("optimizing...");
 
         for _ in 0..self.nb_workers {
             let queue = Arc::clone(&self.queue);
             let results = Arc::clone(&results);
             let optimized = Arc::clone(&optimized);
-            let pb = Arc::clone(&pb);
+            let pb = Arc::clone(&self.progress);
 
             let cancel_token = self.cancel_token.clone();
             let dest_dir = self.dest_dir.clone();
@@ -211,9 +234,8 @@ impl ImgOptimizer {
             });
         }
 
-        // TODO(rmanach): move it on main not here
+        // TODO(rmanach): move it on main not here (overwrite progress bar message)
         tokio::spawn({
-            let pb = Arc::clone(&pb);
             let optimizer = self.clone();
             async move {
                 if let Err(e) = tokio::signal::ctrl_c().await {
@@ -222,23 +244,26 @@ impl ImgOptimizer {
 
                 log::warn!("interrupt signal received");
                 optimizer.stop().await;
-                pb.finish_with_message("optimization interrupted");
+                optimizer
+                    .progress
+                    .finish_with_message("optimization interrupted");
             }
         });
 
         self.tracker.close();
         self.tracker.wait().await;
 
-        pb.finish_with_message("optimization complete");
+        self.progress.finish_with_message("optimization complete");
+
         log::info!(
             "optimization finished in {:.2}s",
             start.elapsed().as_secs_f64()
         );
 
-        Ok(OptimizerResult {
+        OptimizerResult {
             orig: file_group.clone(),
             opti: results.read().await.clone(),
             optimized: optimized.load(Ordering::Relaxed),
-        })
+        }
     }
 }