ContactResolver: implement in-memory cache for positive results

kordophoned/src/daemon/contact_resolver/mod.rs

@@ -1,6 +1,8 @@
 pub mod eds;
 pub use eds::EDSContactResolverBackend;
 
+use std::collections::HashMap;
+
 pub trait ContactResolverBackend {
     type ContactID;
 
@@ -13,6 +15,8 @@ pub type AnyContactID = String;
 #[derive(Clone)]
 pub struct ContactResolver<T: ContactResolverBackend> {
     backend: T,
+    display_name_cache: HashMap<AnyContactID, String>,
+    contact_id_cache: HashMap<String, AnyContactID>,
 }
 
 impl<T: ContactResolverBackend> ContactResolver<T>
@@ -22,16 +26,34 @@ where
     T: Default,
 {
     pub fn new(backend: T) -> Self {
-        Self { backend }
+        Self { backend, display_name_cache: HashMap::new(), contact_id_cache: HashMap::new() }
     }
 
-    pub fn resolve_contact_id(&self, address: &str) -> Option<AnyContactID> {
+    pub fn resolve_contact_id(&mut self, address: &str) -> Option<AnyContactID> {
-        self.backend.resolve_contact_id(address).map(|id| id.into())
+        if let Some(id) = self.contact_id_cache.get(address) {
+            return Some(id.clone());
+        }
+
+        let id = self.backend.resolve_contact_id(address).map(|id| id.into());
+        if let Some(ref id) = id {
+            self.contact_id_cache.insert(address.to_string(), id.clone());
+        }
+
+        id
     }
 
-    pub fn get_contact_display_name(&self, contact_id: &AnyContactID) -> Option<String> {
+    pub fn get_contact_display_name(&mut self, contact_id: &AnyContactID) -> Option<String> {
+        if let Some(display_name) = self.display_name_cache.get(contact_id) {
+            return Some(display_name.clone());
+        }
+
         let backend_contact_id: T::ContactID = T::ContactID::from((*contact_id).clone());
-        self.backend.get_contact_display_name(&backend_contact_id)
+        let display_name = self.backend.get_contact_display_name(&backend_contact_id);
+        if let Some(ref display_name) = display_name {
+            self.display_name_cache.insert(contact_id.to_string(), display_name.clone());
+        }
+
+        display_name
     }
 }
 

kordophoned/src/daemon/mod.rs

@@ -507,7 +507,7 @@ impl Daemon {
 
         // Insert each conversation
         let num_conversations = db_conversations.len();
-        let contact_resolver = ContactResolver::new(EDSContactResolverBackend::default());
+        let mut contact_resolver = ContactResolver::new(EDSContactResolverBackend::default());
         for conversation in db_conversations {
             // Insert or update conversation and its participants
             database

kordophoned/src/dbus/agent.rs

@@ -173,7 +173,7 @@ impl DBusAgent {
             .map_err(|e| MethodErr::failed(&format!("Daemon error: {}", e)))
     }
     
-    fn resolve_participant_display_name(&self, participant: &Participant) -> String {
+    fn resolve_participant_display_name(&mut self, participant: &Participant) -> String {
         match participant {
             // Me (we should use a special string here...)
             Participant::Me => "(Me)".to_string(),