Refactor file store

README.md

@@ -42,7 +42,7 @@ The project is split up into several crates in the `/crates` directory:
 - [`wallet`](./crates/wallet): Contains the central high level `Wallet` type that is built from the low-level mechanisms provided by the other components
 - [`chain`](./crates/chain): Tools for storing and indexing chain data
 - [`persist`](./crates/persist): Types that define data persistence of a BDK wallet
-- [`file_store`](./crates/file_store): A (experimental) persistence backend for storing chain data in a single file.
+- [`file_store`](./crates/file_store): Persistence backend for storing chain data in a single file. Intended for testing and development purposes, not for production.
 - [`esplora`](./crates/esplora): Extends the [`esplora-client`] crate with methods to fetch chain data from an esplora HTTP server in the form that [`bdk_chain`] and `Wallet` can consume.
 - [`electrum`](./crates/electrum): Extends the [`electrum-client`] crate with methods to fetch chain data from an electrum server in the form that [`bdk_chain`] and `Wallet` can consume.
 

crates/file_store/src/entry_iter.rs

@@ -1,3 +1,4 @@
+use crate::StoreError;
 use bincode::Options;
 use std::{
     fs::File,
@@ -37,7 +38,7 @@ impl<T> Iterator for EntryIter<'_, T>
 where
     T: serde::de::DeserializeOwned,
 {
-    type Item = Result<T, IterError>;
+    type Item = Result<T, StoreError>;
 
     fn next(&mut self) -> Option<Self::Item> {
         if self.finished {
@@ -63,7 +64,7 @@ where
                         }
                     }
                     self.db_file.seek(io::SeekFrom::Start(pos_before_read))?;
-                    Err(IterError::Bincode(*e))
+                    Err(StoreError::Bincode(*e))
                 }
             }
         })()
@@ -80,29 +81,3 @@ impl<T> Drop for EntryIter<'_, T> {
         }
     }
 }
-
-/// Error type for [`EntryIter`].
-#[derive(Debug)]
-pub enum IterError {
-    /// Failure to read from the file.
-    Io(io::Error),
-    /// Failure to decode data from the file.
-    Bincode(bincode::ErrorKind),
-}
-
-impl core::fmt::Display for IterError {
-    fn fmt(&self, f: &mut core::fmt::Formatter<'_>) -> core::fmt::Result {
-        match self {
-            IterError::Io(e) => write!(f, "io error trying to read entry {}", e),
-            IterError::Bincode(e) => write!(f, "bincode error while reading entry {}", e),
-        }
-    }
-}
-
-impl From<io::Error> for IterError {
-    fn from(value: io::Error) -> Self {
-        IterError::Io(value)
-    }
-}
-
-impl std::error::Error for IterError {}

crates/file_store/src/lib.rs

@@ -13,14 +13,16 @@ pub(crate) fn bincode_options() -> impl bincode::Options {
 
 /// Error that occurs due to problems encountered with the file.
 #[derive(Debug)]
-pub enum FileError {
+pub enum StoreError {
     /// IO error, this may mean that the file is too short.
     Io(io::Error),
     /// Magic bytes do not match what is expected.
     InvalidMagicBytes { got: Vec<u8>, expected: Vec<u8> },
+    /// Failure to decode data from the file.
+    Bincode(bincode::ErrorKind),
 }
 
-impl core::fmt::Display for FileError {
+impl core::fmt::Display for StoreError {
     fn fmt(&self, f: &mut core::fmt::Formatter<'_>) -> core::fmt::Result {
         match self {
             Self::Io(e) => write!(f, "io error trying to read file: {}", e),
@@ -29,14 +31,15 @@ impl core::fmt::Display for FileError {
                 "file has invalid magic bytes: expected={:?} got={:?}",
                 expected, got,
             ),
+            Self::Bincode(e) => write!(f, "bincode error while reading entry {}", e),
         }
     }
 }
 
-impl From<io::Error> for FileError {
+impl From<io::Error> for StoreError {
     fn from(value: io::Error) -> Self {
         Self::Io(value)
     }
 }
 
-impl std::error::Error for FileError {}
+impl std::error::Error for StoreError {}