Implement clone_repo and start handling synchronization requests

crates/crdb/src/crdb.rs

@@ -6,7 +6,7 @@ mod sync;
 mod test;
 
 use anyhow::{anyhow, Result};
-use collections::{btree_map, BTreeMap, HashMap};
+use collections::{btree_map, BTreeMap, Bound, HashMap};
 use dense_id::DenseId;
 use futures::{future::BoxFuture, FutureExt};
 use messages::{MessageEnvelope, Operation, RequestEnvelope};
@@ -51,12 +51,12 @@ type RevisionId = SmallVec<[OperationId; 2]>;
 pub struct ReplicaId(u32);
 
 #[derive(Copy, Clone, Debug, Default, PartialEq, Eq, PartialOrd, Ord, Serialize, Deserialize)]
-struct OperationCount(usize);
+pub struct OperationCount(usize);
 
 #[derive(Copy, Clone, Debug, Default, PartialEq, Eq, PartialOrd, Ord, Serialize, Deserialize)]
 pub struct OperationId {
-    replica_id: ReplicaId,
-    operation_count: OperationCount,
+    pub replica_id: ReplicaId,
+    pub operation_count: OperationCount,
 }
 
 impl OperationId {
@@ -204,7 +204,7 @@ impl<N: ClientNetwork> Clone for Client<N> {
         Self {
             db: self.db.clone(),
             network: self.network.clone(),
-            repo_rooms: Default::default(),
+            repo_rooms: self.repo_rooms.clone(),
         }
     }
 }
@@ -235,7 +235,29 @@ impl<N: ClientNetwork> Client<N> {
     }
 
     pub fn clone_repo(&self, name: impl Into<Arc<str>>) -> impl Future<Output = Result<Repo>> {
-        async move { todo!() }
+        let this = self.clone();
+        let name = name.into();
+        async move {
+            let response = this.request(messages::CloneRepo { name }).await?;
+            let repo_id = response.repo_id;
+            let room = RepoRoom::new(
+                this.clone(),
+                repo_id,
+                this.network.room(response.credentials),
+            );
+            room.handle_messages(Self::handle_remote_operation);
+            this.repo_rooms.lock().insert(repo_id, room);
+            this.db
+                .snapshot
+                .lock()
+                .repos
+                .insert(repo_id, Default::default());
+
+            Ok(Repo {
+                id: repo_id,
+                db: this.db.clone(),
+            })
+        }
     }
 
     pub fn publish_repo(
@@ -262,7 +284,18 @@ impl<N: ClientNetwork> Client<N> {
         }
     }
 
-    fn handle_remote_operation(self, repo_id: RepoId, operation: Operation) {}
+    fn handle_remote_operation(self, repo_id: RepoId, operation: Operation) {
+        let update = self
+            .db
+            .snapshot
+            .lock()
+            .repos
+            .update(&repo_id, |repo| repo.apply_operation(operation));
+        assert!(
+            update.is_some(),
+            "received an operation for an unknown repo"
+        );
+    }
 
     fn request<R: Request>(&self, request: R) -> BoxFuture<Result<R::Response>> {
         let envelope: RequestEnvelope = request.into();
@@ -285,6 +318,7 @@ struct Server<N> {
         >,
     >,
     repo_ids_by_name: Arc<Mutex<BTreeMap<Arc<str>, RepoId>>>,
+    next_replica_ids_by_repo_id: Arc<Mutex<BTreeMap<RepoId, ReplicaId>>>,
 }
 
 impl<N: ServerNetwork> Clone for Server<N> {
@@ -292,8 +326,9 @@ impl<N: ServerNetwork> Clone for Server<N> {
         Self {
             db: self.db.clone(),
             network: self.network.clone(),
-            repo_ids_by_name: Default::default(),
-            request_handlers: Default::default(),
+            repo_ids_by_name: self.repo_ids_by_name.clone(),
+            request_handlers: self.request_handlers.clone(),
+            next_replica_ids_by_repo_id: self.next_replica_ids_by_repo_id.clone(),
         }
     }
 }
@@ -304,11 +339,14 @@ impl<N: ServerNetwork> Server<N> {
         let this = Self {
             db: Db::new(),
             network: network.clone(),
-            repo_ids_by_name: Default::default(),
             request_handlers: Default::default(),
+            repo_ids_by_name: Default::default(),
+            next_replica_ids_by_repo_id: Default::default(),
         };
 
         this.handle_requests(Self::handle_publish_repo);
+        this.handle_requests(Self::handle_clone_repo);
+        this.handle_requests(Self::handle_sync_repo);
         let request_handlers = this.request_handlers.clone();
 
         network.handle_requests(move |user, request_bytes| {
@@ -364,6 +402,9 @@ impl<N: ServerNetwork> Server<N> {
                 entry.insert(request.id);
             }
         }
+        self.next_replica_ids_by_repo_id
+            .lock()
+            .insert(request.id, ReplicaId(1));
 
         let name = RoomName(request.id.to_string().into());
         self.network.create_room(&name).await?;
@@ -373,6 +414,76 @@ impl<N: ServerNetwork> Server<N> {
             credentials: RoomCredentials { name, token },
         })
     }
+
+    async fn handle_clone_repo(
+        self,
+        user: User,
+        request: messages::CloneRepo,
+    ) -> Result<messages::CloneRepoResponse> {
+        let repo_id = *self
+            .repo_ids_by_name
+            .lock()
+            .get(&request.name)
+            .ok_or_else(|| anyhow!("repo not found"))?;
+        let name = RoomName(repo_id.to_string().into());
+        let token = self.network.grant_room_access(&name, user.login.as_ref());
+        let replica_id = {
+            let mut next_replica_ids = self.next_replica_ids_by_repo_id.lock();
+            let next_replica_id = next_replica_ids.get_mut(&repo_id).unwrap();
+            let replica_id = *next_replica_id;
+            next_replica_id.0 += 1;
+            replica_id
+        };
+        Ok(messages::CloneRepoResponse {
+            repo_id,
+            replica_id,
+            credentials: RoomCredentials { name, token },
+        })
+    }
+
+    async fn handle_sync_repo(
+        self,
+        _user: User,
+        request: messages::SyncRepo,
+    ) -> Result<messages::SyncRepoResponse> {
+        let repo = self
+            .db
+            .snapshot
+            .lock()
+            .repos
+            .get(&request.id)
+            .ok_or_else(|| anyhow!("repo not found"))?
+            .clone();
+        let mut response = messages::SyncRepoResponse {
+            operations: Default::default(),
+        };
+        for (replica_id, end_op_count) in repo.max_operation_ids.iter() {
+            let end_op = OperationId {
+                replica_id: *replica_id,
+                operation_count: *end_op_count,
+            };
+            if let Some(start_op_count) = request.max_operation_ids.get(&replica_id) {
+                let start_op = OperationId {
+                    replica_id: *replica_id,
+                    operation_count: *start_op_count,
+                };
+                response.operations.extend(
+                    repo.operations
+                        .range((Bound::Excluded(&start_op), Bound::Included(&end_op)))
+                        .map(|(_, op)| op.clone()),
+                );
+            } else {
+                let start_op = OperationId::new(*replica_id);
+                response.operations.extend(
+                    repo.operations
+                        .range((Bound::Included(&start_op), Bound::Included(&end_op)))
+                        .map(|(_, op)| op.clone()),
+                );
+            }
+        }
+
+        Ok(response)
+    }
 }
 
 #[derive(Clone)]
@@ -432,6 +543,12 @@ impl Repo {
             .update(&self.id, |repo| {
                 let (operation, result) = f(repo);
                 repo.operations.insert(operation.id(), operation.clone());
+                let replica_id = operation.id().replica_id;
+                let count = operation.id().operation_count;
+                if repo.max_operation_ids.get(&replica_id).copied() < Some(count) {
+                    repo.max_operation_ids.insert(replica_id, count);
+                }
+
                 if let Some(operation_created) = self.db.local_operation_created.as_ref() {
                     operation_created(self.id, operation);
                 }
@@ -1058,6 +1175,7 @@ struct RepoSnapshot {
     branches: TreeMap<OperationId, BranchSnapshot>,
     operations: TreeMap<OperationId, Operation>,
     revisions: TreeMap<RevisionId, Revision>,
+    max_operation_ids: TreeMap<ReplicaId, OperationCount>,
 }
 
 impl RepoSnapshot {
@@ -1087,6 +1205,10 @@ impl RepoSnapshot {
         });
         (operation, branch_id)
     }
+
+    fn apply_operation(&mut self, operation: Operation) {
+        todo!()
+    }
 }
 
 #[derive(Clone, Debug)]

crates/crdb/src/messages.rs

@@ -1,20 +1,25 @@
 use crate::{
     operations::{CreateBranch, CreateDocument, Edit},
-    OperationId, RepoId, Request, RevisionId, RoomCredentials,
+    OperationCount, OperationId, ReplicaId, RepoId, Request, RevisionId, RoomCredentials,
 };
+use collections::BTreeMap;
 use serde::{Deserialize, Serialize};
 use std::{any::Any, sync::Arc};
 
 #[derive(Clone, Debug, Serialize, Deserialize)]
 pub enum RequestEnvelope {
     PublishRepo(PublishRepo),
+    CloneRepo(CloneRepo),
+    SyncRepo(SyncRepo),
 }
 
 impl RequestEnvelope {
     pub fn unwrap(self) -> Box<dyn Any> {
-        Box::new(match self {
-            RequestEnvelope::PublishRepo(request) => request,
-        })
+        match self {
+            RequestEnvelope::PublishRepo(request) => Box::new(request),
+            RequestEnvelope::CloneRepo(request) => Box::new(request),
+            RequestEnvelope::SyncRepo(request) => Box::new(request),
+        }
     }
 }
 
@@ -45,6 +50,49 @@ pub struct PublishRepoResponse {
     pub credentials: RoomCredentials,
 }
 
+#[derive(Clone, Debug, Serialize, Deserialize)]
+pub struct CloneRepo {
+    pub name: Arc<str>,
+}
+
+impl Request for CloneRepo {
+    type Response = CloneRepoResponse;
+}
+
+impl Into<RequestEnvelope> for CloneRepo {
+    fn into(self) -> RequestEnvelope {
+        RequestEnvelope::CloneRepo(self)
+    }
+}
+
+#[derive(Clone, Serialize, Deserialize)]
+pub struct CloneRepoResponse {
+    pub repo_id: RepoId,
+    pub replica_id: ReplicaId,
+    pub credentials: RoomCredentials,
+}
+
+#[derive(Clone, Debug, Serialize, Deserialize)]
+pub struct SyncRepo {
+    pub id: RepoId,
+    pub max_operation_ids: BTreeMap<ReplicaId, OperationCount>,
+}
+
+impl Request for SyncRepo {
+    type Response = SyncRepoResponse;
+}
+
+impl Into<RequestEnvelope> for SyncRepo {
+    fn into(self) -> RequestEnvelope {
+        RequestEnvelope::SyncRepo(self)
+    }
+}
+
+#[derive(Clone, Serialize, Deserialize)]
+pub struct SyncRepoResponse {
+    pub operations: Vec<Operation>,
+}
+
 #[derive(Clone, Debug, Serialize, Deserialize)]
 pub enum MessageEnvelope {
     Operation(Operation),

crates/sum_tree/src/tree_map.rs

@@ -1,4 +1,8 @@
-use std::{cmp::Ordering, fmt::Debug};
+use std::{
+    cmp::Ordering,
+    fmt::Debug,
+    ops::{Bound, RangeBounds},
+};
 
 use crate::{Bias, Dimension, Edit, Item, KeyedItem, SeekTarget, SumTree, Summary};
 
@@ -93,6 +97,32 @@ impl<K: Clone + Debug + Default + Ord, V: Clone + Debug> TreeMap<K, V> {
         cursor.item().map(|item| (&item.key, &item.value))
     }
 
+    pub fn range<'a, R>(&self, range: R) -> impl Iterator<Item = (&K, &V)>
+    where
+        K: 'a,
+        R: RangeBounds<&'a K>,
+    {
+        let mut cursor = self.0.cursor::<MapKeyRef<'_, K>>();
+        match range.start_bound() {
+            Bound::Included(start) => {
+                let start = MapKeyRef(Some(*start));
+                cursor.seek(&start, Bias::Left, &());
+            }
+            Bound::Excluded(start) => {
+                let start = MapKeyRef(Some(*start));
+                cursor.seek(&start, Bias::Right, &());
+            }
+            Bound::Unbounded => cursor.next(&()),
+        }
+        cursor
+            .map(|entry| (&entry.key, &entry.value))
+            .take_while(move |(key, _)| match range.end_bound() {
+                Bound::Included(end) => key <= end,
+                Bound::Excluded(end) => key < end,
+                Bound::Unbounded => true,
+            })
+    }
+
     pub fn iter_from<'a>(&'a self, from: &'a K) -> impl Iterator<Item = (&K, &V)> + '_ {
         let mut cursor = self.0.cursor::<MapKeyRef<'_, K>>();
         let from_key = MapKeyRef(Some(from));