the state before switching to dynamic dispatch for stores

src/core/instance/mod.rs

@@ -130,7 +130,19 @@ impl<S: Store> Instance<S> {
     //fn from(value: T) -> Self {
     //}
 //}
+    pub fn migrate_to_store<New: Store>(&mut self, new_store: New) -> MizeResult<Instance<New>> {
+        let old_store = self.store;
 
+        for id in old_store.id_iter()? {
+            let data = self.store.get_value_data_full(self.id_from_string(id))?;
+
+            let id_of_new_store = new_store.new_id()?;
+            new_store.set(self.id_from_string(id_of_new_store), data.to_owned())?;
+        };
+
+        self.store = new_store as S;
+        Ok(Instance { store: new_store, subs: self.subs, peers: self.peers, id_pool: self.id_pool })
+    }
 }
 
 impl<S: Store> fmt::Debug for Instance<S> {

src/core/instance/store.rs

@@ -1,6 +1,12 @@
+
+use std::iter::Map;
+use std::option::Iter;
+
 use crate::error::MizeResult;
 use crate::item::{Item, ItemData};
 use crate::id::MizeId;
+use crate::memstore::MemStore;
+use crate::instance::Instance;
 
 pub trait Store {
     // should have the ability to be multi threaded, if the underlying implementation supports 
@@ -23,5 +29,7 @@ pub trait Store {
     fn get_value_raw(&self, id: MizeId) -> MizeResult<Vec<u8>>;
 
     fn get_value_data_full(&self, id: MizeId) -> MizeResult<ItemData>;
+
+    fn id_iter(&self) -> MizeResult<impl Iterator<Item=String> + '_>;
 }