crypto: Go through the user device keys in parallel

matrix_sdk_crypto/src/identities/manager.rs

@@ -23,7 +23,7 @@ use tracing::{trace, warn};
 use matrix_sdk_common::{
     api::r0::keys::get_keys::Response as KeysQueryResponse,
     encryption::DeviceKeys,
-    identifiers::{DeviceId, DeviceIdBox, UserId},
+    identifiers::{DeviceIdBox, UserId},
 };
 
 use crate::{
@@ -64,10 +64,6 @@ impl IdentityManager {
         &self.user_id
     }
 
-    fn device_id(&self) -> &DeviceId {
-        &self.device_id
-    }
-
     /// Receive a successful keys query response.
     ///
     /// Returns a list of devices newly discovered devices and devices that
@@ -82,7 +78,7 @@ impl IdentityManager {
         response: &KeysQueryResponse,
     ) -> OlmResult<(DeviceChanges, IdentityChanges)> {
         let changed_devices = self
-            .handle_devices_from_key_query(&response.device_keys)
+            .handle_devices_from_key_query(response.device_keys.clone())
             .await?;
         let changed_identities = self.handle_cross_singing_keys(response).await?;
 
@@ -140,27 +136,24 @@ impl IdentityManager {
         }
     }
 
-    /// Handle the device keys part of a key query response.
-    ///
-    /// # Arguments
-    ///
-    /// * `device_keys_map` - A map holding the device keys of the users for
-    /// which the key query was done.
-    ///
-    /// Returns a list of devices that changed. Changed here means either
-    /// they are new, one of their properties has changed or they got deleted.
-    async fn handle_devices_from_key_query(
-        &self,
-        device_keys_map: &BTreeMap<UserId, BTreeMap<DeviceIdBox, DeviceKeys>>,
+    async fn update_user_devices(
+        store: Store,
+        own_user_id: Arc<UserId>,
+        own_device_id: Arc<DeviceIdBox>,
+        user_id: UserId,
+        device_map: BTreeMap<DeviceIdBox, DeviceKeys>,
     ) -> StoreResult<DeviceChanges> {
         let mut changes = DeviceChanges::default();
 
-        for (user_id, device_map) in device_keys_map {
-            let tasks = device_map.iter().filter_map(|(device_id, device_keys)| {
+        let current_devices: HashSet<DeviceIdBox> = device_map.keys().cloned().collect();
+
+        let tasks = device_map
+            .into_iter()
+            .filter_map(|(device_id, device_keys)| {
                 // We don't need our own device in the device store.
-                if user_id == self.user_id() && &**device_id == self.device_id() {
+                if user_id == *own_user_id && device_id == *own_device_id {
                     None
-                } else if user_id != &device_keys.user_id || device_id != &device_keys.device_id {
+                } else if user_id != device_keys.user_id || device_id != device_keys.device_id {
                     warn!(
                         "Mismatch in device keys payload of device {}|{} from user {}|{}",
                         device_id, device_keys.device_id, user_id, device_keys.user_id
@@ -168,8 +161,8 @@ impl IdentityManager {
                     None
                 } else {
                     Some(tokio::spawn(Self::update_or_create_device(
-                        self.store.clone(),
-                        device_keys.clone(),
+                        store.clone(),
+                        device_keys,
                     )))
                 }
             });
@@ -184,8 +177,8 @@ impl IdentityManager {
             }
         }
 
-            let current_devices: HashSet<&DeviceIdBox> = device_map.keys().collect();
-            let stored_devices = self.store.get_readonly_devices(&user_id).await?;
+        let current_devices: HashSet<&DeviceIdBox> = current_devices.iter().collect();
+        let stored_devices = store.get_readonly_devices(&user_id).await?;
         let stored_devices_set: HashSet<&DeviceIdBox> = stored_devices.keys().collect();
 
         let deleted_devices_set = stored_devices_set.difference(&current_devices);
@@ -196,6 +189,42 @@ impl IdentityManager {
                 changes.deleted.push(device.clone());
             }
         }
+
+        Ok(changes)
+    }
+
+    /// Handle the device keys part of a key query response.
+    ///
+    /// # Arguments
+    ///
+    /// * `device_keys_map` - A map holding the device keys of the users for
+    /// which the key query was done.
+    ///
+    /// Returns a list of devices that changed. Changed here means either
+    /// they are new, one of their properties has changed or they got deleted.
+    async fn handle_devices_from_key_query(
+        &self,
+        device_keys_map: BTreeMap<UserId, BTreeMap<DeviceIdBox, DeviceKeys>>,
+    ) -> StoreResult<DeviceChanges> {
+        let mut changes = DeviceChanges::default();
+
+        let tasks = device_keys_map
+            .into_iter()
+            .map(|(user_id, device_keys_map)| {
+                tokio::spawn(Self::update_user_devices(
+                    self.store.clone(),
+                    self.user_id.clone(),
+                    self.device_id.clone(),
+                    user_id,
+                    device_keys_map,
+                ))
+            });
+
+        let results = join_all(tasks).await;
+
+        for result in results {
+            let change_fragment = result.expect("Panic while updating user devices")?;
+            changes.extend(change_fragment);
         }
 
         Ok(changes)

matrix_sdk_crypto/src/store/mod.rs

@@ -126,6 +126,15 @@ pub struct DeviceChanges {
     pub deleted: Vec<ReadOnlyDevice>,
 }
 
+impl DeviceChanges {
+    /// Merge the given `DeviceChanges` into this instance of `DeviceChanges`.
+    pub fn extend(&mut self, other: DeviceChanges) {
+        self.new.extend(other.new);
+        self.changed.extend(other.changed);
+        self.deleted.extend(other.deleted);
+    }
+}
+
 impl Store {
     pub fn new(
         user_id: Arc<UserId>,