Playlist example: save analysis to a file

.github/workflows/rust.yml

@@ -33,4 +33,4 @@ jobs:
     - name: Build benches
       run: cargo +nightly-2021-04-01 bench --verbose --features=bench --no-run
     - name: Build examples
-      run: cargo build --examples --verbose
+      run: cargo build --examples --verbose --features=serde

Cargo.lock

@@ -97,6 +97,7 @@ dependencies = [
  "ripemd160",
  "rustfft",
  "serde",
+ "serde_json",
  "strum",
  "strum_macros",
  "thiserror",
@@ -518,6 +519,12 @@ dependencies = [
  "either",
 ]
 
+[[package]]
+name = "itoa"
+version = "0.4.8"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b71991ff56294aa922b450139ee08b3bfc70982c6b2c7562771375cf73542dd4"
+
 [[package]]
 name = "jobserver"
 version = "0.1.24"
@@ -1037,6 +1044,12 @@ dependencies = [
  "transpose",
 ]
 
+[[package]]
+name = "ryu"
+version = "1.0.5"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "71d301d4193d031abdd79ff7e3dd721168a9572ef3fe51a1517aba235bd8f86e"
+
 [[package]]
 name = "scopeguard"
 version = "1.1.0"
@@ -1063,6 +1076,17 @@ dependencies = [
  "syn",
 ]
 
+[[package]]
+name = "serde_json"
+version = "1.0.68"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "0f690853975602e1bfe1ccbf50504d67174e3bcf340f23b5ea9992e0587a52d8"
+dependencies = [
+ "itoa",
+ "ryu",
+ "serde",
+]
+
 [[package]]
 name = "sha-1"
 version = "0.8.2"

Cargo.toml

@@ -49,3 +49,4 @@ serde = { version = "1.0", optional = true, features = ["derive"] }
 mime_guess = "2.0.3"
 glob = "0.3.0"
 anyhow = "1.0.45"
+serde_json = "1.0.59"

examples/playlist.rs

@@ -3,16 +3,19 @@ use bliss_audio::distance::{closest_to_first_song, dedup_playlist, euclidean_dis
 use bliss_audio::{library::analyze_paths_streaming, Song};
 use glob::glob;
 use mime_guess;
+use serde_json;
 use std::env;
 use std::fs;
-use std::path::Path;
+use std::io::BufReader;
+use std::path::{Path, PathBuf};
 
 /* Analyzes a folder recursively, and make a playlist out of the file
  * provided by the user. */
 // TODO still:
-// * Save the results somewhere to avoid analyzing stuff over and over
+// * Mention it in the README
 // * Make the output file configurable
 // * Allow to choose between outputing to stdout and a file
+#[cfg(feature = "serde")]
 fn main() -> Result<()> {
     let args: Vec<String> = env::args().skip(1).collect();
     if args.len() > 3 || args.len() < 2 {
@@ -27,7 +30,20 @@ fn main() -> Result<()> {
     let folder = &args[0];
     let file = fs::canonicalize(&args[1])?;
     let pattern = Path::new(folder).join("**").join("*");
-    let songs = glob(&pattern.to_string_lossy())?
+
+    let mut songs: Vec<Song> = Vec::new();
+    let analysis_file = fs::File::open("./songs.json");
+    if let Ok(f) = analysis_file {
+        let reader = BufReader::new(f);
+        songs = serde_json::from_reader(reader)?;
+    }
+
+    let analyzed_paths = songs
+        .iter()
+        .map(|s| s.path.to_owned())
+        .collect::<Vec<PathBuf>>();
+
+    let paths = glob(&pattern.to_string_lossy())?
         .map(|e| fs::canonicalize(e.unwrap()).unwrap())
         .filter(|e| match mime_guess::from_path(e).first() {
             Some(m) => m.type_() == "audio",
@@ -35,7 +51,14 @@ fn main() -> Result<()> {
         })
         .map(|x| x.to_string_lossy().to_string())
         .collect::<Vec<String>>();
-    let rx = analyze_paths_streaming(songs)?;
+
+    let rx = analyze_paths_streaming(
+        paths
+            .iter()
+            .filter(|p| !analyzed_paths.contains(&PathBuf::from(p)))
+            .map(|p| p.to_owned())
+            .collect(),
+    )?;
     let first_song = Song::new(file)?;
     let mut analyzed_songs = vec![first_song.to_owned()];
     for (path, result) in rx.iter() {
@@ -44,9 +67,16 @@ fn main() -> Result<()> {
             Err(e) => println!("error analyzing {}: {}", path, e),
         };
     }
-    closest_to_first_song(&first_song, &mut analyzed_songs, euclidean_distance);
-    dedup_playlist(&mut analyzed_songs, None);
-    let playlist = analyzed_songs
+    analyzed_songs.extend_from_slice(&songs);
+    let serialized = serde_json::to_string(&analyzed_songs).unwrap();
+    let mut songs_to_chose_from = analyzed_songs
+        .into_iter()
+        .filter(|x| x == &first_song || paths.contains(&x.path.to_string_lossy().to_string()))
+        .collect();
+    closest_to_first_song(&first_song, &mut songs_to_chose_from, euclidean_distance);
+    dedup_playlist(&mut songs_to_chose_from, None);
+    fs::write("./songs.json", serialized)?;
+    let playlist = songs_to_chose_from
         .iter()
         .map(|s| s.path.to_string_lossy().to_string())
         .collect::<Vec<String>>()
@@ -55,3 +85,8 @@ fn main() -> Result<()> {
     fs::write("./playlist.m3u", playlist)?;
     Ok(())
 }
+
+#[cfg(not(feature = "serde"))]
+fn main() {
+    println!("You need the serde feature enabled to run this file.");
+}

src/lib.rs

@@ -63,7 +63,7 @@
 //! ```
 #![cfg_attr(feature = "bench", feature(test))]
 #![warn(missing_docs)]
-#![warn(missing_doc_code_examples)]
+#![warn(rustdoc::missing_doc_code_examples)]
 mod chroma;
 pub mod distance;
 pub mod library;