Improve usability of wrapped tables

src/database/wrapped.rs

@@ -3,6 +3,7 @@ use crate::environment::Txn;
 use crate::wrapper::ByteWrapper;
 use anyhow::Context;
 use libmdbx::{TransactionKind, RW};
+use std::borrow::Borrow;
 
 pub struct WrappedTable<K, V> {
     pub raw: RawTable<[u8], [u8]>,
@@ -14,11 +15,11 @@ impl<K: ByteWrapper, V: ByteWrapper> WrappedTable<K, V> {
     pub fn get<'txn, TK: TransactionKind>(
         &self,
         txn: &Txn<'txn, TK>,
-        k: impl AsRef<K::Item>,
+        k: impl Borrow<K::Item>,
     ) -> anyhow::Result<Option<V::Item>> {
         let k_bytes = self
             .k_wrapper
-            .dump_to_db_bytes(k.as_ref())
+            .dump_to_db_bytes(k.borrow())
             .context("whilst converting key to bytes")?;
 
         self.raw
@@ -30,16 +31,16 @@ impl<K: ByteWrapper, V: ByteWrapper> WrappedTable<K, V> {
     pub fn put<'txn>(
         &self,
         txn: &Txn<'txn, RW>,
-        k: impl AsRef<K::Item>,
+        k: impl Borrow<K::Item>,
-        v: impl AsRef<V::Item>,
+        v: impl Borrow<V::Item>,
     ) -> anyhow::Result<()> {
         let k_bytes = self
             .k_wrapper
-            .dump_to_db_bytes(k.as_ref())
+            .dump_to_db_bytes(k.borrow())
             .context("whilst converting key to bytes")?;
         let v_bytes = self
             .v_wrapper
-            .dump_to_db_bytes(v.as_ref())
+            .dump_to_db_bytes(v.borrow())
             .context("whilst converting value to bytes")?;
 
         self.raw.put(txn, k_bytes, v_bytes)?;
@@ -50,11 +51,11 @@ impl<K: ByteWrapper, V: ByteWrapper> WrappedTable<K, V> {
     pub fn delete<'txn>(
         &self,
         txn: &Txn<'txn, RW>,
-        k: impl AsRef<K::Item>,
+        k: impl Borrow<K::Item>,
     ) -> anyhow::Result<bool> {
         let k_bytes = self
             .k_wrapper
-            .dump_to_db_bytes(k.as_ref())
+            .dump_to_db_bytes(k.borrow())
             .context("whilst converting key to bytes")?;
 
         self.raw.delete(txn, k_bytes)

src/wrapper.rs

@@ -17,6 +17,14 @@ pub struct SerdeBareWrapper<T> {
     phantom: PhantomData<T>,
 }
 
+impl<T> Default for SerdeBareWrapper<T> {
+    fn default() -> Self {
+        SerdeBareWrapper {
+            phantom: Default::default(),
+        }
+    }
+}
+
 impl<T: Serialize + DeserializeOwned> ByteWrapper for SerdeBareWrapper<T> {
     type Item = T;
 
@@ -58,6 +66,40 @@ impl<T: ByteWrapper> ByteWrapper for CompressorWrapper<T> {
     }
 }
 
+impl<T> CompressorWrapper<T> {
+    pub fn new_with(inner: T) -> anyhow::Result<Self> {
+        let compressor = Compressor::new(13)?;
+        let decompressor = Decompressor::new()?;
+
+        Ok(CompressorWrapper {
+            inner,
+            compressor: Mutex::new(compressor),
+            decompressor: Mutex::new(decompressor),
+        })
+    }
+
+    pub fn new() -> anyhow::Result<Self>
+    where
+        T: Default,
+    {
+        let inner: T = Default::default();
+
+        Self::new_with(inner)
+    }
+}
+
+impl ByteWrapper for String {
+    type Item = String;
+
+    fn load_from_db_bytes(&self, bytes: &[u8]) -> anyhow::Result<Self::Item> {
+        Ok(std::str::from_utf8(bytes)?.to_string())
+    }
+
+    fn dump_to_db_bytes(&self, item: &Self::Item) -> anyhow::Result<Vec<u8>> {
+        Ok(item.as_bytes().to_vec())
+    }
+}
+
 impl<T: ByteWrapper> ByteWrapper for Arc<T> {
     type Item = T::Item;