chore: add License for storage_engine (#412)

Signed-off-by: Gaius <gaius.qi@gmail.com>

Cargo.lock

@@ -903,7 +903,7 @@ dependencies = [
 
 [[package]]
 name = "dragonfly-client"
-version = "0.1.34"
+version = "0.1.35"
 dependencies = [
  "anyhow",
  "bytes",
@@ -962,7 +962,7 @@ dependencies = [
 
 [[package]]
 name = "dragonfly-client-backend"
-version = "0.1.34"
+version = "0.1.35"
 dependencies = [
  "dragonfly-client-core",
  "futures",
@@ -980,7 +980,7 @@ dependencies = [
 
 [[package]]
 name = "dragonfly-client-config"
-version = "0.1.34"
+version = "0.1.35"
 dependencies = [
  "dragonfly-client-core",
  "home",
@@ -999,7 +999,7 @@ dependencies = [
 
 [[package]]
 name = "dragonfly-client-core"
-version = "0.1.34"
+version = "0.1.35"
 dependencies = [
  "libloading",
  "reqwest",
@@ -1010,7 +1010,7 @@ dependencies = [
 
 [[package]]
 name = "dragonfly-client-init"
-version = "0.1.34"
+version = "0.1.35"
 dependencies = [
  "anyhow",
  "clap",
@@ -1026,7 +1026,7 @@ dependencies = [
 
 [[package]]
 name = "dragonfly-client-storage"
-version = "0.1.34"
+version = "0.1.35"
 dependencies = [
  "base16ct",
  "chrono",
@@ -1049,7 +1049,7 @@ dependencies = [
 
 [[package]]
 name = "dragonfly-client-util"
-version = "0.1.34"
+version = "0.1.35"
 dependencies = [
  "dragonfly-api",
  "dragonfly-client-core",
@@ -1495,7 +1495,7 @@ dependencies = [
 
 [[package]]
 name = "hdfs"
-version = "0.1.34"
+version = "0.1.35"
 dependencies = [
  "dragonfly-client-backend",
  "dragonfly-client-core",

dragonfly-client-storage/src/lib.rs

@@ -26,7 +26,6 @@ use tokio::io::AsyncRead;
 
 pub mod content;
 pub mod metadata;
-
 pub mod storage_engine;
 
 // DEFAULT_WAIT_FOR_PIECE_FINISHED_INTERVAL is the default interval for waiting for the piece to be finished.

dragonfly-client-storage/src/metadata.rs

@@ -58,8 +58,9 @@ pub struct Task {
     pub finished_at: Option<NaiveDateTime>,
 }
 
+// Task implements the task database object.
 impl DatabaseObject for Task {
-    /// NAMESPACE is the namespace of [Task] objects.
+    // NAMESPACE is the namespace of [Task] objects.
     const NAMESPACE: &'static str = "task";
 }
 
@@ -146,8 +147,9 @@ pub struct Piece {
     pub finished_at: Option<NaiveDateTime>,
 }
 
+// Piece implements the piece database object.
 impl DatabaseObject for Piece {
-    /// NAMESPACE is the namespace of [Piece] objects.
+    // NAMESPACE is the namespace of [Piece] objects.
     const NAMESPACE: &'static str = "piece";
 }
 

dragonfly-client-storage/src/storage_engine/mod.rs

@@ -1,3 +1,19 @@
+/*
+ *     Copyright 2024 The Dragonfly Authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
 use dragonfly_client_core::{
     error::{ErrorType, OrErr},
     Result,
@@ -41,12 +57,16 @@ impl<T: for<'db> StorageEngine<'db>> StorageEngineOwned for T {}
 pub trait Operations {
     /// get gets the object by key.
     fn get<O: DatabaseObject>(&self, key: &[u8]) -> Result<Option<O>>;
+
     /// put puts the object by key.
     fn put<O: DatabaseObject>(&self, key: &[u8], value: &O) -> Result<()>;
+
     /// delete deletes the object by key.
     fn delete<O: DatabaseObject>(&self, key: &[u8]) -> Result<()>;
+
     /// iter iterates all objects.
     fn iter<O: DatabaseObject>(&self) -> Result<impl Iterator<Item = Result<(Box<[u8]>, O)>>>;
+
     /// prefix_iter iterates all objects with prefix.
     fn prefix_iter<O: DatabaseObject>(
         &self,
@@ -58,8 +78,10 @@ pub trait Operations {
 pub trait Transaction: Operations {
     /// get_for_update gets the object for update.
     fn get_for_update<O: DatabaseObject>(&self, key: &[u8]) -> Result<Option<O>>;
+
     /// commit commits the transaction.
     fn commit(self) -> Result<()>;
+
     /// rollback rolls back the transaction.
     fn rollback(&self) -> Result<()>;
 }

dragonfly-client-storage/src/storage_engine/rocksdb.rs

@@ -1,27 +1,45 @@
-use std::{ops::Deref, path::Path};
+/*
+ *     Copyright 2024 The Dragonfly Authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
 
+use crate::storage_engine::{DatabaseObject, Operations, StorageEngine, Transaction};
 use dragonfly_client_core::{
     error::{ErrorType, OrErr},
     Error, Result,
 };
-
+use std::{ops::Deref, path::Path};
 use tracing::info;
 
-use crate::storage_engine::{DatabaseObject, Operations, StorageEngine, Transaction};
-
 /// RocksdbStorageEngine is a storage engine based on rocksdb.
 pub struct RocksdbStorageEngine {
+    // inner is the inner rocksdb transaction db.
     inner: rocksdb::TransactionDB,
 }
 
+// RocksdbStorageEngine implements deref of the storage engine.
 impl Deref for RocksdbStorageEngine {
+    // Target is the inner rocksdb transaction db.
     type Target = rocksdb::TransactionDB;
 
+    // deref returns the inner rocksdb transaction db.
     fn deref(&self) -> &Self::Target {
         &self.inner
     }
 }
 
+// RocksdbStorageEngine implements the storage engine of the rocksdb.
 impl RocksdbStorageEngine {
     /// DEFAULT_DIR_NAME is the default directory name to store metadata.
     const DEFAULT_DIR_NAME: &'static str = "metadata";
@@ -75,7 +93,9 @@ impl RocksdbStorageEngine {
     }
 }
 
+// RocksdbStorageEngine implements the storage engine operations.
 impl Operations for RocksdbStorageEngine {
+    // get gets the object by key.
     fn get<O: DatabaseObject>(&self, key: &[u8]) -> Result<Option<O>> {
         let cf = cf_handle::<O>(self)?;
         let value = self.get_cf(cf, key).or_err(ErrorType::StorageError)?;
@@ -85,6 +105,7 @@ impl Operations for RocksdbStorageEngine {
         }
     }
 
+    // put puts the object by key.
     fn put<O: DatabaseObject>(&self, key: &[u8], value: &O) -> Result<()> {
         let cf = cf_handle::<O>(self)?;
         let serialized = value.serialized()?;
@@ -93,12 +114,14 @@ impl Operations for RocksdbStorageEngine {
         Ok(())
     }
 
+    // delete deletes the object by key.
     fn delete<O: DatabaseObject>(&self, key: &[u8]) -> Result<()> {
         let cf = cf_handle::<O>(self)?;
         self.delete_cf(cf, key).or_err(ErrorType::StorageError)?;
         Ok(())
     }
 
+    // iter iterates all objects.
     fn iter<O: DatabaseObject>(&self) -> Result<impl Iterator<Item = Result<(Box<[u8]>, O)>>> {
         let cf = cf_handle::<O>(self)?;
         let iter = self.iterator_cf(cf, rocksdb::IteratorMode::Start);
@@ -108,6 +131,7 @@ impl Operations for RocksdbStorageEngine {
         }))
     }
 
+    // prefix_iter iterates all objects with prefix.
     fn prefix_iter<O: DatabaseObject>(
         &self,
         prefix: &[u8],
@@ -121,9 +145,12 @@ impl Operations for RocksdbStorageEngine {
     }
 }
 
+// RocksdbStorageEngine implements the transaction of the storage engine.
 impl<'db> StorageEngine<'db> for RocksdbStorageEngine {
+    // Txn is the transaction type.
     type Txn = RocksdbTransaction<'db>;
 
+    // start_transaction starts a transaction.
     fn start_transaction(&'db self) -> RocksdbTransaction<'db> {
         let txn = self.transaction();
         RocksdbTransaction { txn, db: self }
@@ -132,11 +159,16 @@ impl<'db> StorageEngine<'db> for RocksdbStorageEngine {
 
 /// RocksdbTransaction wraps a rocksdb transaction.
 pub struct RocksdbTransaction<'db> {
+    // txn is the inner rocksdb transaction.
     txn: rocksdb::Transaction<'db, rocksdb::TransactionDB>,
+
+    // db is the rocksdb storage engine.
     db: &'db rocksdb::TransactionDB,
 }
 
+// RocksdbTransaction implements the transaction operations.
 impl Operations for RocksdbTransaction<'_> {
+    // get gets the object by key.
     fn get<O: DatabaseObject>(&self, key: &[u8]) -> Result<Option<O>> {
         let cf = cf_handle::<O>(self.db)?;
         let value = self.txn.get_cf(cf, key).or_err(ErrorType::StorageError)?;
@@ -146,6 +178,7 @@ impl Operations for RocksdbTransaction<'_> {
         }
     }
 
+    // put puts the object by key.
     fn put<O: DatabaseObject>(&self, key: &[u8], value: &O) -> Result<()> {
         let cf = cf_handle::<O>(self.db)?;
         let serialized = value.serialized()?;
@@ -155,6 +188,7 @@ impl Operations for RocksdbTransaction<'_> {
         Ok(())
     }
 
+    // delete deletes the object by key.
     fn delete<O: DatabaseObject>(&self, key: &[u8]) -> Result<()> {
         let cf = cf_handle::<O>(self.db)?;
         self.txn
@@ -163,6 +197,7 @@ impl Operations for RocksdbTransaction<'_> {
         Ok(())
     }
 
+    // iter iterates all objects.
     fn iter<O: DatabaseObject>(&self) -> Result<impl Iterator<Item = Result<(Box<[u8]>, O)>>> {
         let cf = cf_handle::<O>(self.db)?;
         let iter = self.txn.iterator_cf(cf, rocksdb::IteratorMode::Start);
@@ -172,6 +207,7 @@ impl Operations for RocksdbTransaction<'_> {
         }))
     }
 
+    // prefix_iter iterates all objects with prefix.
     fn prefix_iter<O: DatabaseObject>(
         &self,
         prefix: &[u8],
@@ -185,7 +221,9 @@ impl Operations for RocksdbTransaction<'_> {
     }
 }
 
+// RocksdbTransaction implements the transaction operations.
 impl Transaction for RocksdbTransaction<'_> {
+    // get_for_update gets the object for update.
     fn get_for_update<O: DatabaseObject>(&self, key: &[u8]) -> Result<Option<O>> {
         let cf = cf_handle::<O>(self.db)?;
         let value = self
@@ -198,11 +236,13 @@ impl Transaction for RocksdbTransaction<'_> {
         }
     }
 
+    // commit commits the transaction.
     fn commit(self) -> Result<()> {
         self.txn.commit().or_err(ErrorType::StorageError)?;
         Ok(())
     }
 
+    // rollback rolls back the transaction.
     fn rollback(&self) -> Result<()> {
         self.txn.rollback().or_err(ErrorType::StorageError)?;
         Ok(())