refactor: split read_cache

sdgb-cli/src/utils/helpers/mod.rs

@@ -24,6 +24,27 @@ use bincode::{BorrowDecode, Encode, borrow_decode_from_slice};
 
 use crate::{EARLY_QUIT, cache};
 
+pub fn read_cache<D>(
+    definition: TableDefinition<'_, u32, Vec<u8>>,
+) -> Result<Vec<D>, Box<dyn snafu::Error>>
+where
+    D: for<'d> BorrowDecode<'d, ()>,
+{
+    let txn = cache::read_txn()?;
+    let table = cache::open_table_ro(&txn, definition)?;
+
+    let config =
+        bincode::config::Configuration::<bincode::config::LittleEndian>::default().with_no_limit();
+
+    Ok(table
+        .iter()?
+        .flatten()
+        .map(|d| borrow_decode_from_slice(&d.1.value(), config))
+        .flatten()
+        .map(|(value, _)| value)
+        .collect::<Vec<D>>())
+}
+
 pub fn dump_cache<D>(
     output_path: impl AsRef<Path>,
     definition: TableDefinition<'_, u32, Vec<u8>>,
@@ -40,23 +61,10 @@ where
     #[cfg(file_lock_ready)]
     file.try_lock()?;
 
-    let txn = cache::read_txn()?;
+    let data = read_cache::<D>(definition)?;
-    let table = cache::open_table_ro(&txn, definition)?;
-
-    let config =
-        bincode::config::Configuration::<bincode::config::LittleEndian>::default().with_no_limit();
-
-    let user_ids = table
-        .iter()?
-        .flatten()
-        .map(|d| borrow_decode_from_slice(&d.1.value(), config))
-        .flatten()
-        .map(|(value, _)| value)
-        .collect::<Vec<D>>();
-
     let writer = BufWriter::new(file);
-    serde_json::to_writer(writer, &user_ids)?;
+    serde_json::to_writer(writer, &data)?;
-    info!("dumped {} user id", user_ids.len());
+    info!("dumped {} user id", data.len());
 
     Ok(())
 }