From 0c4ae6fd0b5e84114af7f6a1290a18659df0b458 Mon Sep 17 00:00:00 2001
From: Andrew Morris <voltrevo@gmail.com>
Date: Thu, 2 Nov 2023 22:50:57 +1100
Subject: [PATCH] Implement StorageReader for Storage

---
 storage/src/memory_backend.rs  |  4 ++++
 storage/src/sled_backend.rs    |  4 ++++
 storage/src/storage.rs         | 13 +++++++++++++
 storage/src/storage_backend.rs |  4 +++-
 storage/src/storage_io.rs      |  1 -
 5 files changed, 24 insertions(+), 2 deletions(-)

diff --git a/storage/src/memory_backend.rs b/storage/src/memory_backend.rs
index cba1ab9..fd648fc 100644
--- a/storage/src/memory_backend.rs
+++ b/storage/src/memory_backend.rs
@@ -25,6 +25,10 @@ impl StorageBackend for MemoryBackend {
   type Tx<'a> = MemoryTx<'a>;
   type TxMut<'a> = MemoryTxMut<'a>;
 
+  fn read_bytes<T>(&self, ptr: StoragePtr<T>) -> Result<Option<Vec<u8>>, GenericError> {
+    Ok(self.data.get(&ptr.data).cloned())
+  }
+
   fn transaction<F, T>(&self, self_weak: Weak<RefCell<Self>>, f: F) -> Result<T, Box<dyn Error>>
   where
     F: Fn(&mut Self::Tx<'_>) -> Result<T, GenericError>,
diff --git a/storage/src/sled_backend.rs b/storage/src/sled_backend.rs
index a53500d..8f04d1e 100644
--- a/storage/src/sled_backend.rs
+++ b/storage/src/sled_backend.rs
@@ -37,6 +37,10 @@ impl StorageBackend for SledBackend {
   type Tx<'a> = SledTx<'a>;
   type TxMut<'a> = SledTxMut<'a>;
 
+  fn read_bytes<T>(&self, ptr: StoragePtr<T>) -> Result<Option<Vec<u8>>, GenericError> {
+    Ok(self.db.get(ptr.to_bytes())?.map(|value| value.to_vec()))
+  }
+
   fn transaction<F, T>(&self, self_weak: Weak<RefCell<Self>>, f: F) -> Result<T, Box<dyn Error>>
   where
     F: Fn(&mut Self::Tx<'_>) -> Result<T, GenericError>,
diff --git a/storage/src/storage.rs b/storage/src/storage.rs
index 7bd7e08..53023b1 100644
--- a/storage/src/storage.rs
+++ b/storage/src/storage.rs
@@ -118,3 +118,16 @@ impl<SB: StorageBackend> Storage<SB> {
     })
   }
 }
+
+impl<SB: StorageBackend> StorageReader<SB> for Storage<SB> {
+  fn read_bytes<T>(
+    &self,
+    ptr: crate::StoragePtr<T>,
+  ) -> Result<Option<Vec<u8>>, crate::GenericError> {
+    self.sb.borrow().read_bytes(ptr)
+  }
+
+  fn get_backend(&self) -> std::rc::Weak<RefCell<SB>> {
+    Rc::downgrade(&self.sb)
+  }
+}
diff --git a/storage/src/storage_backend.rs b/storage/src/storage_backend.rs
index 15bfca5..4a6a051 100644
--- a/storage/src/storage_backend.rs
+++ b/storage/src/storage_backend.rs
@@ -2,7 +2,7 @@ use std::{cell::RefCell, error::Error, rc::Weak};
 
 use crate::{
   storage_io::{StorageReader, StorageTxMut},
-  GenericError,
+  GenericError, StoragePtr,
 };
 
 pub trait StorageBackend: Sized {
@@ -10,6 +10,8 @@ pub trait StorageBackend: Sized {
   type Tx<'a>: StorageReader<Self>;
   type TxMut<'a>: StorageTxMut<Self>;
 
+  fn read_bytes<T>(&self, ptr: StoragePtr<T>) -> Result<Option<Vec<u8>>, GenericError>;
+
   fn transaction<F, T>(&self, self_weak: Weak<RefCell<Self>>, f: F) -> Result<T, Box<dyn Error>>
   where
     F: Fn(&mut Self::Tx<'_>) -> Result<T, GenericError>;
diff --git a/storage/src/storage_io.rs b/storage/src/storage_io.rs
index caef8d7..69439a4 100644
--- a/storage/src/storage_io.rs
+++ b/storage/src/storage_io.rs
@@ -10,7 +10,6 @@ use crate::{
 
 pub trait StorageReader<SB: StorageBackend>: Sized {
   fn read_bytes<T>(&self, ptr: StoragePtr<T>) -> Result<Option<Vec<u8>>, GenericError>;
-
   fn get_backend(&self) -> Weak<RefCell<SB>>;
 
   fn get_auto_ptr<SE: StorageEntity<SB>>(