feat: implement production cas v1

infrastructure/src/cas.rs

@@ -1 +1,5 @@
-//! CAS 存储实现占位
+//! CAS 仓储适配器。
+
+pub mod filesystem;
+
+pub use filesystem::FileSystemCasRepository;

infrastructure/src/cas/filesystem.rs

@@ -1,152 +1,134 @@
-//! CAS 文件系统实现
+//! 文件系统 CAS 仓储适配层。
 //!
-//! 基于文件系统的内容寻址存储实现
+//! 这里不实现 CAS 核心算法，只将 `bat-cas-engine` 适配到
+//! `bat-core::repositories::CasRepository`。
 
 use async_trait::async_trait;
+use bat_cas_engine::hash::Hash;
+use bat_cas_engine::repository as engine_repository;
 use bat_core::repositories::cas_repository::{CasRepository, ObjectId};
-use blake3::Hasher;
 use std::path::PathBuf;
-use tokio::fs;
-use tokio::io::AsyncWriteExt;
+use tokio::sync::OnceCell;
 
-/// 文件系统 CAS Repository
-///
-/// 使用文件系统存储对象，目录结构：
-/// ```text
-/// cas_root/
-/// ├── objects/
-/// │   ├── ab/
-/// │   │   ├── cd/
-/// │   │   │   └── abcd1234...
-/// └── refs.db (SQLite)
-/// ```
+/// 文件系统 CAS Repository 适配器。
 pub struct FileSystemCasRepository {
-    /// CAS 根目录
     root: PathBuf,
+    inner: OnceCell<engine_repository::FileSystemCasRepository>,
 }
 
 impl FileSystemCasRepository {
-    /// 创建新的文件系统 CAS Repository
-    ///
-    /// # 参数
-    ///
-    /// - `root`: CAS 根目录
-    ///
-    /// # 示例
-    ///
-    /// ```rust,ignore
-    /// let repo = FileSystemCasRepository::new("/path/to/cas");
-    /// ```
+    /// 创建新的文件系统 CAS Repository 适配器。
     pub fn new(root: impl Into<PathBuf>) -> Self {
         Self {
             root: root.into(),
+            inner: OnceCell::new(),
         }
     }
 
-    /// 计算对象 Hash
-    fn compute_hash(data: &[u8]) -> ObjectId {
-        let mut hasher = Hasher::new();
-        hasher.update(data);
-        hasher.finalize().to_hex().to_string()
-    }
-
-    /// 获取对象路径
-    fn object_path(&self, id: &ObjectId) -> PathBuf {
-        let prefix1 = &id[0..2];
-        let prefix2 = &id[2..4];
-        self.root
-            .join("objects")
-            .join(prefix1)
-            .join(prefix2)
-            .join(id)
-    }
-
-    /// 初始化存储
+    /// 初始化底层 CAS 引擎。
     pub async fn init(&self) -> bat_core::Result<()> {
-        fs::create_dir_all(self.root.join("objects"))
+        self.engine().await.map(|_| ())
+    }
+
+    async fn engine(&self) -> bat_core::Result<&engine_repository::FileSystemCasRepository> {
+        self.inner
+            .get_or_try_init(|| async {
+                engine_repository::FileSystemCasRepository::new(&self.root)
+                    .await
+                    .map_err(Self::map_error)
+            })
             .await
-            .map_err(bat_core::Error::Io)?;
-        Ok(())
+    }
+
+    fn parse_object_id(id: &ObjectId) -> bat_core::Result<Hash> {
+        id.parse::<Hash>()
+            .map_err(|error| bat_core::Error::InvalidArgument(error.to_string()))
+    }
+
+    fn map_error(error: bat_cas_engine::CasError) -> bat_core::Error {
+        match error {
+            bat_cas_engine::CasError::Io(error) => bat_core::Error::Io(error),
+            bat_cas_engine::CasError::ObjectNotFound(id) => bat_core::Error::NotFound(id),
+            bat_cas_engine::CasError::HashMismatch { expected, actual } => {
+                bat_core::Error::InvalidArgument(format!(
+                    "Hash mismatch: expected {}, got {}",
+                    expected, actual
+                ))
+            }
+            bat_cas_engine::CasError::InvalidHash(hash) => {
+                bat_core::Error::InvalidArgument(format!("Invalid hash: {}", hash))
+            }
+            bat_cas_engine::CasError::ReferenceUnderflow(hash) => bat_core::Error::InvalidArgument(
+                format!("Reference count is already zero: {}", hash),
+            ),
+            bat_cas_engine::CasError::Database(message) => {
+                bat_core::Error::Other(anyhow::anyhow!("CAS metadata error: {}", message))
+            }
+            bat_cas_engine::CasError::Other(error) => bat_core::Error::Other(error),
+        }
     }
 }
 
 #[async_trait]
 impl CasRepository for FileSystemCasRepository {
     async fn store(&self, data: &[u8]) -> bat_core::Result<ObjectId> {
-        let hash = Self::compute_hash(data);
-        let path = self.object_path(&hash);
-
-        // 如果对象已存在，直接返回
-        if path.exists() {
-            return Ok(hash);
-        }
-
-        // 创建父目录
-        if let Some(parent) = path.parent() {
-            fs::create_dir_all(parent)
-                .await
-                .map_err(bat_core::Error::Io)?;
-        }
-
-        // 写入对象
-        let mut file = fs::File::create(&path)
+        let hash = self
+            .engine()
+            .await?
+            .store(data)
             .await
-            .map_err(bat_core::Error::Io)?;
-        file.write_all(data)
-            .await
-            .map_err(bat_core::Error::Io)?;
-        file.sync_all()
-            .await
-            .map_err(bat_core::Error::Io)?;
-
-        Ok(hash)
+            .map_err(Self::map_error)?;
+        Ok(hash.to_string())
     }
 
     async fn get(&self, id: &ObjectId) -> bat_core::Result<Vec<u8>> {
-        let path = self.object_path(id);
-
-        if !path.exists() {
-            return Err(bat_core::Error::NotFound(format!("Object not found: {}", id)));
-        }
-
-        let data = fs::read(&path)
+        let hash = Self::parse_object_id(id)?;
+        self.engine()
+            .await?
+            .get(&hash)
             .await
-            .map_err(bat_core::Error::Io)?;
-
-        // 验证 Hash
-        let computed_hash = Self::compute_hash(&data);
-        if &computed_hash != id {
-            return Err(bat_core::Error::InvalidArgument(format!(
-                "Hash mismatch: expected {}, got {}",
-                id, computed_hash
-            )));
-        }
-
-        Ok(data)
+            .map_err(Self::map_error)
     }
 
     async fn exists(&self, id: &ObjectId) -> bool {
-        self.object_path(id).exists()
+        let Ok(hash) = Self::parse_object_id(id) else {
+            return false;
+        };
+        let Ok(engine) = self.engine().await else {
+            return false;
+        };
+        engine.exists(&hash).await
     }
 
-    async fn add_reference(&self, _id: &ObjectId) -> bat_core::Result<u64> {
-        // TODO: Phase 1 Week 3 - 实现引用计数
-        Ok(1)
+    async fn add_reference(&self, id: &ObjectId) -> bat_core::Result<u64> {
+        let hash = Self::parse_object_id(id)?;
+        self.engine()
+            .await?
+            .add_reference(&hash)
+            .await
+            .map_err(Self::map_error)
     }
 
-    async fn remove_reference(&self, _id: &ObjectId) -> bat_core::Result<u64> {
-        // TODO: Phase 1 Week 3 - 实现引用计数
-        Ok(0)
+    async fn remove_reference(&self, id: &ObjectId) -> bat_core::Result<u64> {
+        let hash = Self::parse_object_id(id)?;
+        self.engine()
+            .await?
+            .remove_reference(&hash)
+            .await
+            .map_err(Self::map_error)
     }
 
-    async fn get_reference_count(&self, _id: &ObjectId) -> bat_core::Result<u64> {
-        // TODO: Phase 1 Week 3 - 实现引用计数
-        Ok(1)
+    async fn get_reference_count(&self, id: &ObjectId) -> bat_core::Result<u64> {
+        let hash = Self::parse_object_id(id)?;
+        self.engine()
+            .await?
+            .get_reference_count(&hash)
+            .await
+            .map_err(Self::map_error)
     }
 
     async fn gc(&self) -> bat_core::Result<u64> {
-        // TODO: Phase 1 Week 3 - 实现垃圾回收
-        Ok(0)
+        self.engine().await?.gc().await.map_err(Self::map_error)
     }
 }
 
@@ -156,7 +138,7 @@ mod tests {
     use tempfile::TempDir;
 
     #[tokio::test]
-    async fn test_store_and_get() {
+    async fn store_get_and_reference_count() {
         let temp_dir = TempDir::new().unwrap();
         let repo = FileSystemCasRepository::new(temp_dir.path());
         repo.init().await.unwrap();
@@ -166,39 +148,56 @@ mod tests {
 
         let retrieved = repo.get(&id).await.unwrap();
         assert_eq!(data, retrieved.as_slice());
+        assert_eq!(repo.get_reference_count(&id).await.unwrap(), 1);
     }
 
     #[tokio::test]
-    async fn test_exists() {
+    async fn duplicate_store_increments_reference_count() {
         let temp_dir = TempDir::new().unwrap();
         let repo = FileSystemCasRepository::new(temp_dir.path());
         repo.init().await.unwrap();
 
-        let data = b"Test data";
-        let id = repo.store(data).await.unwrap();
-
-        assert!(repo.exists(&id).await);
-        assert!(!repo.exists(&"nonexistent".to_string()).await);
-    }
-
-    #[tokio::test]
-    async fn test_deduplication() {
-        let temp_dir = TempDir::new().unwrap();
-        let repo = FileSystemCasRepository::new(temp_dir.path());
-        repo.init().await.unwrap();
-
-        let data = b"Duplicate data";
-        let id1 = repo.store(data).await.unwrap();
-        let id2 = repo.store(data).await.unwrap();
+        let id1 = repo.store(b"Duplicate data").await.unwrap();
+        let id2 = repo.store(b"Duplicate data").await.unwrap();
 
         assert_eq!(id1, id2);
+        assert_eq!(repo.get_reference_count(&id1).await.unwrap(), 2);
     }
 
-    #[test]
-    fn test_compute_hash() {
-        let data = b"test";
-        let hash = FileSystemCasRepository::compute_hash(data);
-        assert!(!hash.is_empty());
-        assert_eq!(hash.len(), 64); // BLAKE3 produces 32 bytes = 64 hex chars
+    #[tokio::test]
+    async fn gc_removes_zero_reference_objects() {
+        let temp_dir = TempDir::new().unwrap();
+        let repo = FileSystemCasRepository::new(temp_dir.path());
+        repo.init().await.unwrap();
+
+        let id = repo.store(b"collect me").await.unwrap();
+        assert_eq!(repo.remove_reference(&id).await.unwrap(), 0);
+        assert_eq!(repo.gc().await.unwrap(), 1);
+
+        assert!(!repo.exists(&id).await);
+        assert!(matches!(
+            repo.get(&id).await,
+            Err(bat_core::Error::NotFound(_))
+        ));
+    }
+
+    #[tokio::test]
+    async fn invalid_object_id_is_rejected() {
+        let temp_dir = TempDir::new().unwrap();
+        let repo = FileSystemCasRepository::new(temp_dir.path());
+        repo.init().await.unwrap();
+
+        let error = repo.get(&"not-a-hash".to_string()).await.unwrap_err();
+        assert!(matches!(error, bat_core::Error::InvalidArgument(_)));
+    }
+
+    #[tokio::test]
+    async fn store_returns_blake3_hex_object_id() {
+        let temp_dir = TempDir::new().unwrap();
+        let repo = FileSystemCasRepository::new(temp_dir.path());
+
+        let hash = repo.store(b"test").await.unwrap();
+
+        assert_eq!(hash.len(), 64);
     }
 }

infrastructure/src/lib.rs

@@ -12,5 +12,7 @@
 
 pub mod cas;
 
+pub use cas::FileSystemCasRepository;
+
 /// Infrastructure 版本号
 pub const VERSION: &str = env!("CARGO_PKG_VERSION");