change: Rust APIの脱Tokioと、voicevox_core::{tokio→nonblocking} (#831)

Tokioに依存したプログラムは、async-stdやsmolで使うことはできない。一方、
現在のVOICEVOX CORE Rust APIのTokio依存部分は
`tokio::task::spawn_blocking`のみである。そのため
`tokio::task::spawn_blocking`を、同等の機能を持つblockingクレートのも
のに置き換えることでRust APIの"脱Tokio"を行う。

https://docs.rs/crate/blocking

またこの"脱Tokio"に伴い、Rust APIの`voicevox_core::tokio`を
`voicevox_core::nonblocking`にリネームする。

Python APIではpyo3-asyncioが現在Tokio版かasync-std版しかない状態なので、
Tokioに依存した状態のままにしてある。またtest_utilやdownloaderではこれま
で通りreqwestに依存する。

また将来`Synthesizer`や`OpenJtalk`なども`trait Async`をベースにした設計
にすることを考えているが、本PRではTODOコメントを残すのみにしてある。

#830 (comment)

Cargo.toml

@@ -12,6 +12,7 @@ async-fs = "2.1.2"
 async_zip = "=0.0.16"
 bindgen = "0.69.4"
 binstall-tar = "0.4.39"
+blocking = "1.6.1"
 bytes = "1.1.0"
 camino = "1.1.6"
 cargo_metadata = "0.18.1"
@@ -57,6 +58,7 @@ octocrab = { version = "0.19.0", default-features = false }
 once_cell = "1.19.0"
 ouroboros = "0.18.0"
 parse-display = "0.8.2"
+pollster = "0.3.0"
 pretty_assertions = "1.3.0"
 proc-macro2 = "1.0.69"
 pyo3 = "0.20.3"

crates/voicevox_core/Cargo.toml

@@ -18,6 +18,7 @@ link-onnxruntime = []
 anyhow.workspace = true
 async-fs.workspace = true
 async_zip = { workspace = true, features = ["deflate"] }
+blocking.workspace = true
 camino.workspace = true
 const_format.workspace = true
 derive-getters.workspace = true
@@ -27,7 +28,7 @@ duplicate.workspace = true
 easy-ext.workspace = true
 educe.workspace = true
 enum-map.workspace = true
-fs-err = { workspace = true, features = ["tokio"] }
+fs-err.workspace = true
 futures-io.workspace = true
 futures-lite.workspace = true
 futures-util = { workspace = true, features = ["io"] }
@@ -46,14 +47,14 @@ smallvec.workspace = true
 strum = { workspace = true, features = ["derive"] }
 tempfile.workspace = true
 thiserror.workspace = true
-tokio = { workspace = true, features = ["rt"] } # FIXME: feature-gateする
 tracing.workspace = true
 uuid = { workspace = true, features = ["v4", "serde"] }
 voicevox-ort = { workspace = true, features = ["download-binaries", "__init-for-voicevox"] }
 voicevox_core_macros = { path = "../voicevox_core_macros" }
 
 [dev-dependencies]
 heck.workspace = true
+pollster = { workspace = true, features = ["macro"] }
 pretty_assertions.workspace = true
 rstest.workspace = true
 rstest_reuse.workspace = true

crates/voicevox_core/src/__internal/doctest_fixtures.rs

@@ -10,23 +10,23 @@ pub async fn synthesizer_with_sample_voice_model(
         OsString,
     >,
     open_jtalk_dic_dir: impl AsRef<Utf8Path>,
-) -> anyhow::Result<crate::tokio::Synthesizer<crate::tokio::OpenJtalk>> {
-    let syntesizer = crate::tokio::Synthesizer::new(
+) -> anyhow::Result<crate::nonblocking::Synthesizer<crate::nonblocking::OpenJtalk>> {
+    let syntesizer = crate::nonblocking::Synthesizer::new(
         #[cfg(feature = "load-onnxruntime")]
-        crate::tokio::Onnxruntime::load_once()
+        crate::nonblocking::Onnxruntime::load_once()
             .filename(onnxruntime_dylib_path)
             .exec()
             .await?,
         #[cfg(feature = "link-onnxruntime")]
-        crate::tokio::Onnxruntime::init_once().await?,
-        crate::tokio::OpenJtalk::new(open_jtalk_dic_dir).await?,
+        crate::nonblocking::Onnxruntime::init_once().await?,
+        crate::nonblocking::OpenJtalk::new(open_jtalk_dic_dir).await?,
         &InitializeOptions {
             acceleration_mode: AccelerationMode::Cpu,
             ..Default::default()
         },
     )?;
 
-    let model = &crate::tokio::VoiceModel::from_path(voice_model_path).await?;
+    let model = &crate::nonblocking::VoiceModel::from_path(voice_model_path).await?;
     syntesizer.load_voice_model(model).await?;
 
     Ok(syntesizer)

crates/voicevox_core/src/asyncs.rs

@@ -11,8 +11,7 @@
 //! に[`SingleTasked`]を用意している。
 //!
 //! [ブロッキング版API]: crate::blocking
-//! [非同期版API]: crate::tokio
-//! [blocking]: https://docs.rs/crate/blocking
+//! [非同期版API]: crate::nonblocking
 
 use std::{
     io::{self, Read as _, Seek as _, SeekFrom},
@@ -71,8 +70,7 @@ impl Async for SingleTasked {
 ///
 /// [非同期版API]用。
 ///
-/// [blocking]: https://docs.rs/crate/blocking
-/// [非同期版API]: crate::tokio
+/// [非同期版API]: crate::nonblocking
 pub(crate) enum BlockingThreadPool {}
 
 impl Async for BlockingThreadPool {

crates/voicevox_core/src/devices.rs

@@ -52,9 +52,9 @@ fn test_gpu(
 /// しても`cuda`や`dml`は`true`を示しうる。
 ///
 /// ```
-/// # #[tokio::main]
+/// # #[pollster::main]
 /// # async fn main() -> anyhow::Result<()> {
-/// use voicevox_core::{tokio::Onnxruntime, SupportedDevices};
+/// use voicevox_core::{nonblocking::Onnxruntime, SupportedDevices};
 ///
 /// # voicevox_core::blocking::Onnxruntime::load_once()
 /// #     .filename(if cfg!(windows) {

crates/voicevox_core/src/engine/full_context_label.rs

@@ -425,7 +425,7 @@ mod tests {
     #[apply(label_cases)]
     #[tokio::test]
     async fn open_jtalk(text: &str, labels: &[&str], _accent_phrase: &[AccentPhrase]) {
-        let open_jtalk = crate::tokio::OpenJtalk::new(OPEN_JTALK_DIC_DIR)
+        let open_jtalk = crate::nonblocking::OpenJtalk::new(OPEN_JTALK_DIC_DIR)
             .await
             .unwrap();
         assert_eq!(&open_jtalk.extract_fullcontext(text).unwrap(), labels);
@@ -447,7 +447,7 @@ mod tests {
     #[apply(label_cases)]
     #[tokio::test]
     async fn extract_fullcontext(text: &str, _labels: &[&str], accent_phrase: &[AccentPhrase]) {
-        let open_jtalk = crate::tokio::OpenJtalk::new(OPEN_JTALK_DIC_DIR)
+        let open_jtalk = crate::nonblocking::OpenJtalk::new(OPEN_JTALK_DIC_DIR)
             .await
             .unwrap();
         assert_eq!(

crates/voicevox_core/src/engine/open_jtalk.rs

@@ -1,3 +1,16 @@
+// TODO: `VoiceModel`のように、次のような設計にする。
+//
+// ```
+// pub(crate) mod blocking {
+//     pub struct OpenJtalk(Inner<SingleTasked>);
+//     // …
+// }
+// pub(crate) mod nonblocking {
+//     pub struct OpenJtalk(Inner<BlockingThreadPool>);
+//     // …
+// }
+// ```
+
 use ::open_jtalk::Text2MecabError;
 
 #[derive(thiserror::Error, Debug)]
@@ -183,12 +196,19 @@ pub(crate) mod blocking {
     }
 }
 
-pub(crate) mod tokio {
+pub(crate) mod nonblocking {
     use camino::Utf8Path;
 
     use super::FullcontextExtractor;
 
     /// テキスト解析器としてのOpen JTalk。
+    ///
+    /// # Performance
+    ///
+    /// [blocking]クレートにより動いている。詳しくは[`nonblocking`モジュールのドキュメント]を参照。
+    ///
+    /// [blocking]: https://docs.rs/crate/blocking
+    /// [`nonblocking`モジュールのドキュメント]: crate::nonblocking
     #[derive(Clone)]
     pub struct OpenJtalk(super::blocking::OpenJtalk);
 
@@ -206,7 +226,7 @@ pub(crate) mod tokio {
         /// この関数を呼び出した後にユーザー辞書を変更した場合は、再度この関数を呼ぶ必要がある。
         pub async fn use_user_dict(
             &self,
-            user_dict: &crate::tokio::UserDict,
+            user_dict: &crate::nonblocking::UserDict,
         ) -> crate::result::Result<()> {
             let inner = self.0 .0.clone();
             let words = user_dict.to_mecab_format();
@@ -325,7 +345,7 @@ mod tests {
         #[case] text: &str,
         #[case] expected: anyhow::Result<Vec<String>>,
     ) {
-        let open_jtalk = super::tokio::OpenJtalk::new(OPEN_JTALK_DIC_DIR)
+        let open_jtalk = super::nonblocking::OpenJtalk::new(OPEN_JTALK_DIC_DIR)
             .await
             .unwrap();
         let result = open_jtalk.extract_fullcontext(text);
@@ -339,7 +359,7 @@ mod tests {
         #[case] text: &str,
         #[case] expected: anyhow::Result<Vec<String>>,
     ) {
-        let open_jtalk = super::tokio::OpenJtalk::new(OPEN_JTALK_DIC_DIR)
+        let open_jtalk = super::nonblocking::OpenJtalk::new(OPEN_JTALK_DIC_DIR)
             .await
             .unwrap();
         for _ in 0..10 {

crates/voicevox_core/src/infer/runtimes/onnxruntime.rs

@@ -1,3 +1,16 @@
+// TODO: `VoiceModel`のように、次のような設計にする。
+//
+// ```
+// pub(crate) mod blocking {
+//     pub struct Onnxruntime(Inner<SingleTasked>);
+//     // …
+// }
+// pub(crate) mod nonblocking {
+//     pub struct Onnxruntime(Inner<BlockingThreadPool>);
+//     // …
+// }
+// ```
+
 use std::{fmt::Debug, vec};
 
 use anyhow::{anyhow, bail, ensure};
@@ -18,9 +31,6 @@ use super::super::{
     OutputScalarKind, OutputTensor, ParamInfo, PushInputTensor,
 };
 
-// TODO: `trait AsyncRuntime`みたいなものを作って抽象化しながら同期版と非同期版に別個の役割を
-// 持たせる
-// （なぜそうしたいかの理由の一つとしては<https://github.com/VOICEVOX/voicevox_core/issues/687>）
 impl InferenceRuntime for self::blocking::Onnxruntime {
     type Session = ort::Session;
     type RunContext<'a> = OnnxruntimeRunContext<'a>;
@@ -254,7 +264,7 @@ pub(crate) mod blocking {
     /// # Rust APIにおけるインスタンスの共有
     ///
     /// インスタンスは[voicevox-ort]側に作られる。Rustのクレートとしてこのライブラリを利用する場合、
-    /// Tokio版APIやvoicevox-ortを利用する他クレートともインスタンスが共有される。
+    /// 非同期版APIやvoicevox-ortを利用する他クレートともインスタンスが共有される。
     ///
     #[cfg_attr(feature = "load-onnxruntime", doc = "```")]
     #[cfg_attr(not(feature = "load-onnxruntime"), doc = "```compile_fail")]
@@ -268,7 +278,7 @@ pub(crate) mod blocking {
     /// #         .exec()?;
     /// # }
     /// let ort1 = voicevox_core::blocking::Onnxruntime::load_once().exec()?;
-    /// let ort2 = another_lib::tokio::Onnxruntime::get().expect("`ort1`と同一のはず");
+    /// let ort2 = another_lib::nonblocking::Onnxruntime::get().expect("`ort1`と同一のはず");
     /// assert_eq!(ptr_addr(ort1), ptr_addr(ort2));
     ///
     /// fn ptr_addr(obj: &impl Sized) -> usize {
@@ -430,7 +440,7 @@ pub(crate) mod blocking {
     }
 }
 
-pub(crate) mod tokio {
+pub(crate) mod nonblocking {
     use ref_cast::{ref_cast_custom, RefCastCustom};
 
     use crate::SupportedDevices;
@@ -448,15 +458,17 @@ pub(crate) mod tokio {
     #[cfg_attr(not(feature = "load-onnxruntime"), doc = "```compile_fail")]
     /// # use voicevox_core as another_lib;
     /// #
-    /// # #[tokio::main]
+    /// # #[pollster::main]
     /// # async fn main() -> anyhow::Result<()> {
     /// # if cfg!(windows) {
     /// #     // Windows\System32\onnxruntime.dllを回避
     /// #     voicevox_core::blocking::Onnxruntime::load_once()
     /// #         .filename(test_util::ONNXRUNTIME_DYLIB_PATH)
     /// #         .exec()?;
     /// # }
-    /// let ort1 = voicevox_core::tokio::Onnxruntime::load_once().exec().await?;
+    /// let ort1 = voicevox_core::nonblocking::Onnxruntime::load_once()
+    ///     .exec()
+    ///     .await?;
     /// let ort2 = another_lib::blocking::Onnxruntime::get().expect("`ort1`と同一のはず");
     /// assert_eq!(ptr_addr(ort1), ptr_addr(ort2));
     ///
@@ -467,7 +479,13 @@ pub(crate) mod tokio {
     /// # }
     /// ```
     ///
+    /// # Performance
+    ///
+    /// [blocking]クレートにより動いている。詳しくは[`nonblocking`モジュールのドキュメント]を参照。
+    ///
     /// [voicevox-ort]: https://github.com/VOICEVOX/ort
+    /// [blocking]: https://docs.rs/crate/blocking
+    /// [`nonblocking`モジュールのドキュメント]: crate::nonblocking
     #[derive(Debug, RefCastCustom)]
     #[repr(transparent)]
     pub struct Onnxruntime(pub(crate) super::blocking::Onnxruntime);
@@ -584,11 +602,11 @@ mod tests {
 
         assert_eq!(
             super::blocking::Onnxruntime::LIB_NAME,
-            super::tokio::Onnxruntime::LIB_NAME,
+            super::nonblocking::Onnxruntime::LIB_NAME,
         );
         assert_eq!(
             super::blocking::Onnxruntime::LIB_VERSION,
-            super::tokio::Onnxruntime::LIB_VERSION,
+            super::nonblocking::Onnxruntime::LIB_VERSION,
         );
     }
 

crates/voicevox_core/src/lib.rs

@@ -69,7 +69,7 @@ mod voice_model;
 
 pub mod __internal;
 pub mod blocking;
-pub mod tokio;
+pub mod nonblocking;
 
 #[cfg(test)]
 mod test_util;

crates/voicevox_core/src/nonblocking.rs

@@ -0,0 +1,25 @@
+//! 非同期版API。
+//!
+//! # Performance
+//!
+//! これらは[blocking]クレートにより動いている。特定の非同期ランタイムを必要とせず、[pollster]など
+//! でも動かすことができる。
+//!
+//! スレッドプールおよびエグゼキュータはblockingクレートに依存するすべてのプログラム間で共有される。
+//! スレッドプールのサイズは、blockingクレートの説明にある通り`$BLOCKING_MAX_THREADS`で調整すること
+//! ができる。
+//!
+//! [blocking]: https://docs.rs/crate/blocking
+//! [pollster]: https://docs.rs/crate/pollster
+
+pub use crate::{
+    engine::open_jtalk::nonblocking::OpenJtalk,
+    infer::runtimes::onnxruntime::nonblocking::Onnxruntime, synthesizer::nonblocking::Synthesizer,
+    user_dict::dict::nonblocking::UserDict, voice_model::nonblocking::VoiceModel,
+};
+
+pub mod onnxruntime {
+    #[cfg(feature = "load-onnxruntime")]
+    #[cfg_attr(docsrs, doc(cfg(feature = "load-onnxruntime")))]
+    pub use crate::infer::runtimes::onnxruntime::nonblocking::LoadOnce;
+}

crates/voicevox_core/src/status.rs

@@ -408,7 +408,7 @@ mod tests {
                 talk: enum_map!(_ => InferenceSessionOptions::new(0, DeviceSpec::Cpu)),
             },
         );
-        let model = &crate::tokio::VoiceModel::sample().await.unwrap();
+        let model = &crate::nonblocking::VoiceModel::sample().await.unwrap();
         let model_contents = &model.read_inference_models().await.unwrap();
         let result = status.insert_model(model.header(), model_contents);
         assert_debug_fmt_eq!(Ok(()), result);
@@ -424,7 +424,7 @@ mod tests {
                 talk: enum_map!(_ => InferenceSessionOptions::new(0, DeviceSpec::Cpu)),
             },
         );
-        let vvm = &crate::tokio::VoiceModel::sample().await.unwrap();
+        let vvm = &crate::nonblocking::VoiceModel::sample().await.unwrap();
         let model_header = vvm.header();
         let model_contents = &vvm.read_inference_models().await.unwrap();
         assert!(