poc change notification

examples/ReactExample/components/todo-app.js

@@ -48,6 +48,10 @@ export default class TodoApp extends Component {
 
         // This is a Results object, which will live-update.
         this.todoLists = todoLists;
+        todoLists.addListener(function() {
+            console.log("changed");
+        });
+        console.log("registered listener");
 
         // Bind all the methods that we will be passing as props.
         this.renderScene = this.renderScene.bind(this);

src/RealmJS.xcodeproj/project.pbxproj

@@ -114,6 +114,7 @@
 		029048101C0428DF00ABDED4 /* rpc.hpp */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.h; path = rpc.hpp; sourceTree = "<group>"; };
 		029048351C042A3C00ABDED4 /* platform.hpp */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.h; path = platform.hpp; sourceTree = "<group>"; };
 		029048381C042A8F00ABDED4 /* platform.mm */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.objcpp; path = platform.mm; sourceTree = "<group>"; };
+		0290934A1CEFA9170009769E /* js_observable.hpp */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.h; path = js_observable.hpp; sourceTree = "<group>"; };
 		02A3C7A41BC4341500B1A7BE /* libc++.tbd */ = {isa = PBXFileReference; lastKnownFileType = "sourcecode.text-based-dylib-definition"; name = "libc++.tbd"; path = "usr/lib/libc++.tbd"; sourceTree = SDKROOT; };
 		02B58CBC1AE99CEC009B348C /* RealmJSTests.xctest */ = {isa = PBXFileReference; explicitFileType = wrapper.cfbundle; includeInIndex = 0; path = RealmJSTests.xctest; sourceTree = BUILT_PRODUCTS_DIR; };
 		02B58CCD1AE99D4D009B348C /* JavaScriptCore.framework */ = {isa = PBXFileReference; lastKnownFileType = wrapper.framework; name = JavaScriptCore.framework; path = System/Library/Frameworks/JavaScriptCore.framework; sourceTree = SDKROOT; };
@@ -264,6 +265,7 @@
 				F6874A441CAD2ACD00EEEE36 /* JSC */,
 				F62BF9001CAC72C40022BCDC /* Node */,
 				F62A35141C18E783004A917D /* Object Store */,
+				0290934A1CEFA9170009769E /* js_observable.hpp */,
 				F60102F71CBDA6D400EC01BA /* js_collection.hpp */,
 				029048041C0428DF00ABDED4 /* js_list.hpp */,
 				029048061C0428DF00ABDED4 /* js_realm_object.hpp */,

src/js_collection.hpp

@@ -19,6 +19,7 @@
 #pragma once
 
 #include "js_class.hpp"
+#include "js_observable.hpp"
 
 namespace realm {
 namespace js {
@@ -27,7 +28,7 @@ namespace js {
 class Collection {};
 
 template<typename T>
-struct CollectionClass : ClassDefinition<T, Collection> {
+struct CollectionClass : ClassDefinition<T, Collection, ObservableClass<T>> {
     std::string const name = "Collection";
 };
 

src/js_list.hpp

@@ -37,6 +37,7 @@ struct ListClass : ClassDefinition<T, realm::List, CollectionClass<T>> {
     using ContextType = typename T::Context;
     using ObjectType = typename T::Object;
     using ValueType = typename T::Value;
+    using FunctionType = typename T::Function;
     using Object = js::Object<T>;
     using Value = js::Value<T>;
     using ReturnValue = js::ReturnValue<T>;
@@ -59,6 +60,11 @@ struct ListClass : ClassDefinition<T, realm::List, CollectionClass<T>> {
     static void sorted(ContextType, ObjectType, size_t, const ValueType[], ReturnValue &);
     static void is_valid(ContextType, ObjectType, size_t, const ValueType [], ReturnValue &);
     
+    // observable
+    static void add_listener(ContextType, ObjectType, size_t, const ValueType[], ReturnValue &);
+    static void remove_listener(ContextType, ObjectType, size_t, const ValueType[], ReturnValue &);
+    static void remove_all_listeners(ContextType, ObjectType, size_t, const ValueType[], ReturnValue &);
+    
     std::string const name = "List";
 
     MethodMap<T> const methods = {
@@ -71,6 +77,9 @@ struct ListClass : ClassDefinition<T, realm::List, CollectionClass<T>> {
         {"filtered", wrap<filtered>},
         {"sorted", wrap<sorted>},
         {"isValid", wrap<is_valid>},
+        {"addListener", wrap<add_listener>},
+        {"removeListener", wrap<remove_listener>},
+        {"removeAllListeners", wrap<remove_all_listeners>},
     };
 
     PropertyMap<T> const properties = {
@@ -231,5 +240,40 @@ void ListClass<T>::is_valid(ContextType ctx, ObjectType this_object, size_t argc
     return_value.set(get_internal<T, ListClass<T>>(this_object)->is_valid());
 }
     
+template<typename T>
+void ListClass<T>::add_listener(ContextType ctx, ObjectType this_object, size_t argc, const ValueType arguments[], ReturnValue &return_value) {
+    validate_argument_count(argc, 1);
+    
+    auto list = get_internal<T, ListClass<T>>(this_object);
+    auto callback = Value::validated_to_function(ctx, arguments[0]);
+    Protected<FunctionType> protected_callback(ctx, callback);
+    Protected<ObjectType> protected_this(ctx, this_object);
+    Protected<typename T::GlobalContext> protected_ctx(Context<T>::get_global_context(ctx));
+
+    list->add_notification_callback([=](CollectionChangeSet change_set, std::exception_ptr exception) {
+        ValueType arguments[2];
+        arguments[0] = protected_this;
+        arguments[1] = Value::from_undefined(protected_ctx);
+        Function<T>::call(protected_ctx, protected_callback, protected_this, 2, arguments);
+    }, (size_t)(ValueType)callback);
+}
+    
+template<typename T>
+void ListClass<T>::remove_listener(ContextType ctx, ObjectType this_object, size_t argc, const ValueType arguments[], ReturnValue &return_value) {
+    validate_argument_count(argc, 1);
+    
+    auto list = get_internal<T, ListClass<T>>(this_object);
+    auto callback = Value::validated_to_function(ctx, arguments[0]);
+    list->remove_notification_callback((size_t)(ValueType)callback);
+}
+    
+template<typename T>
+void ListClass<T>::remove_all_listeners(ContextType ctx, ObjectType this_object, size_t argc, const ValueType arguments[], ReturnValue &return_value) {
+    validate_argument_count(argc, 0);
+
+    auto list = get_internal<T, ListClass<T>>(this_object);
+    list->remove_all_notification_callbacks();
+}
+
 } // js
 } // realm

src/js_observable.hpp

@@ -0,0 +1,35 @@
+////////////////////////////////////////////////////////////////////////////
+//
+// Copyright 2016 Realm Inc.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+////////////////////////////////////////////////////////////////////////////
+
+#pragma once
+
+#include "js_class.hpp"
+
+namespace realm {
+namespace js {
+
+// Empty class that merely serves as useful type for now.
+class Observable {};
+
+template<typename T>
+struct ObservableClass : ClassDefinition<T, Observable> {
+    std::string const name = "Observable";
+};
+    
+} // js
+} // realm

src/js_realm.hpp

@@ -28,6 +28,7 @@
 #include "js_list.hpp"
 #include "js_results.hpp"
 #include "js_schema.hpp"
+#include "js_observable.hpp"
 
 #include "shared_realm.hpp"
 #include "binding_context.hpp"
@@ -124,7 +125,7 @@ void set_default_path(std::string path);
 void delete_all_realms();
 
 template<typename T>
-class RealmClass : public ClassDefinition<T, SharedRealm> {
+class RealmClass : public ClassDefinition<T, SharedRealm, ObservableClass<T>> {
     using GlobalContextType = typename T::GlobalContext;
     using ContextType = typename T::Context;
     using FunctionType = typename T::Function;

src/js_results.hpp

@@ -34,6 +34,7 @@ struct ResultsClass : ClassDefinition<T, realm::Results, CollectionClass<T>> {
     using ContextType = typename T::Context;
     using ObjectType = typename T::Object;
     using ValueType = typename T::Value;
+    using FunctionType = typename T::Function;
     using Object = js::Object<T>;
     using Value = js::Value<T>;
     using ReturnValue = js::ReturnValue<T>;
@@ -57,6 +58,11 @@ struct ResultsClass : ClassDefinition<T, realm::Results, CollectionClass<T>> {
     static void sorted(ContextType, ObjectType, size_t, const ValueType[], ReturnValue &);
     static void is_valid(ContextType, ObjectType, size_t, const ValueType [], ReturnValue &);
 
+    // observable
+    static void add_listener(ContextType, ObjectType, size_t, const ValueType[], ReturnValue &);
+    static void remove_listener(ContextType, ObjectType, size_t, const ValueType[], ReturnValue &);
+    static void remove_all_listeners(ContextType, ObjectType, size_t, const ValueType[], ReturnValue &);
+    
     std::string const name = "Results";
 
     MethodMap<T> const methods = {
@@ -64,6 +70,9 @@ struct ResultsClass : ClassDefinition<T, realm::Results, CollectionClass<T>> {
         {"filtered", wrap<filtered>},
         {"sorted", wrap<sorted>},
         {"isValid", wrap<is_valid>},
+        {"addListener", wrap<add_listener>},
+        {"removeListener", wrap<remove_listener>},
+        {"removeAllListeners", wrap<remove_all_listeners>},
     };
     
     PropertyMap<T> const properties = {
@@ -240,5 +249,40 @@ void ResultsClass<T>::is_valid(ContextType ctx, ObjectType this_object, size_t a
     return_value.set(get_internal<T, ResultsClass<T>>(this_object)->is_valid());
 }
     
+template<typename T>
+void ResultsClass<T>::add_listener(ContextType ctx, ObjectType this_object, size_t argc, const ValueType arguments[], ReturnValue &return_value) {
+    validate_argument_count(argc, 1);
+    
+    auto list = get_internal<T, ResultsClass<T>>(this_object);
+    auto callback = Value::validated_to_function(ctx, arguments[0]);
+    Protected<FunctionType> protected_callback(ctx, callback);
+    Protected<ObjectType> protected_this(ctx, this_object);
+    Protected<typename T::GlobalContext> protected_ctx(Context<T>::get_global_context(ctx));
+    
+    list->add_notification_callback([=](CollectionChangeSet change_set, std::exception_ptr exception) {
+        ValueType arguments[2];
+        arguments[0] = protected_this;
+        arguments[1] = Value::from_undefined(protected_ctx);
+        Function<T>::call(protected_ctx, protected_callback, protected_this, 2, arguments);
+    }, (size_t)(ValueType)callback);
+}
+
+template<typename T>
+void ResultsClass<T>::remove_listener(ContextType ctx, ObjectType this_object, size_t argc, const ValueType arguments[], ReturnValue &return_value) {
+    validate_argument_count(argc, 1);
+    
+    auto results = get_internal<T, ResultsClass<T>>(this_object);
+    auto callback = Value::validated_to_function(ctx, arguments[0]);
+    results->remove_notification_callback((size_t)(ValueType)callback);
+}
+
+template<typename T>
+void ResultsClass<T>::remove_all_listeners(ContextType ctx, ObjectType this_object, size_t argc, const ValueType arguments[], ReturnValue &return_value) {
+    validate_argument_count(argc, 0);
+    
+    auto results = get_internal<T, ResultsClass<T>>(this_object);
+    results->remove_all_notification_callbacks();
+}
+    
 } // js
 } // realm

src/object-store/src/impl/collection_notifier.cpp

@@ -165,22 +165,19 @@ CollectionNotifier::~CollectionNotifier()
     unregister();
 }
 
-size_t CollectionNotifier::add_callback(CollectionChangeCallback callback)
+size_t CollectionNotifier::add_callback(CollectionChangeCallback callback, size_t token)
 {
     m_realm->verify_thread();
 
-    auto next_token = [=] {
-        size_t token = 0;
+    std::lock_guard<std::mutex> lock(m_callback_mutex);
+    if (token == 0) {
         for (auto& callback : m_callbacks) {
             if (token <= callback.token) {
                 token = callback.token + 1;
             }
         }
-        return token;
-    };
+    }
 
-    std::lock_guard<std::mutex> lock(m_callback_mutex);
-    auto token = next_token();
     m_callbacks.push_back({std::move(callback), token, false});
     if (m_callback_index == npos) { // Don't need to wake up if we're already sending notifications
         Realm::Internal::get_coordinator(*m_realm).send_commit_notifications();
@@ -216,6 +213,12 @@ void CollectionNotifier::remove_callback(size_t token)
     }
 }
 
+void CollectionNotifier::remove_all_callbacks()
+{
+    m_callbacks.clear();
+    m_have_callbacks = false;
+}
+
 void CollectionNotifier::unregister() noexcept
 {
     std::lock_guard<std::mutex> lock(m_realm_mutex);

src/object-store/src/impl/collection_notifier.hpp

@@ -109,11 +109,12 @@ public:
     // Add a callback to be called each time the collection changes
     // This can only be called from the target collection's thread
     // Returns a token which can be passed to remove_callback()
-    size_t add_callback(CollectionChangeCallback callback);
+    size_t add_callback(CollectionChangeCallback callback, size_t token = 0);
     // Remove a previously added token. The token is no longer valid after
     // calling this function and must not be used again. This function can be
     // called from any thread.
     void remove_callback(size_t token);
+    void remove_all_callbacks();
     
     // ------------------------------------------------------------------------
     // API for RealmCoordinator to manage running things and calling callbacks

src/object-store/src/list.cpp

@@ -184,12 +184,27 @@ size_t hash<realm::List>::operator()(realm::List const& list) const
 }
 }
 
-NotificationToken List::add_notification_callback(CollectionChangeCallback cb)
+size_t List::add_notification_callback(CollectionChangeCallback cb, size_t token)
 {
     verify_attached();
     if (!m_notifier) {
         m_notifier = std::make_shared<ListNotifier>(m_link_view, m_realm);
         RealmCoordinator::register_notifier(m_notifier);
     }
-    return {m_notifier, m_notifier->add_callback(std::move(cb))};
+    return m_notifier->add_callback(std::move(cb), token);
+}
+
+NotificationToken List::add_notification_callback(CollectionChangeCallback cb)
+{
+    return {m_notifier, add_notification_callback(cb, 0)};
+}
+
+void List::remove_notification_callback(size_t token)
+{
+    m_notifier->remove_callback(token);
+}
+
+void List::remove_all_notification_callbacks()
+{
+    m_notifier->remove_all_callbacks();
 }

src/object-store/src/list.hpp

@@ -74,6 +74,9 @@ public:
     bool operator==(List const& rgt) const noexcept;
 
     NotificationToken add_notification_callback(CollectionChangeCallback cb);
+    size_t add_notification_callback(CollectionChangeCallback cb, size_t token);
+    void remove_notification_callback(size_t token);
+    void remove_all_notification_callbacks();
     
     // These are implemented in object_accessor.hpp
     template <typename ValueType, typename ContextType>

src/object-store/src/results.cpp

@@ -497,6 +497,22 @@ NotificationToken Results::add_notification_callback(CollectionChangeCallback cb
     return {m_notifier, m_notifier->add_callback(std::move(cb))};
 }
 
+void Results::add_notification_callback(CollectionChangeCallback cb, size_t token)
+{
+    prepare_async();
+    m_notifier->add_callback(std::move(cb), token);
+}
+
+void Results::remove_notification_callback(size_t token)
+{
+    m_notifier->remove_callback(token);
+}
+
+void Results::remove_all_notification_callbacks()
+{
+    m_notifier->remove_all_callbacks();
+}
+
 bool Results::is_in_table_order() const
 {
     switch (m_mode) {

src/object-store/src/results.hpp

@@ -180,6 +180,9 @@ public:
     // and then rerun after each commit (if needed) and redelivered if it changed
     NotificationToken async(std::function<void (std::exception_ptr)> target);
     NotificationToken add_notification_callback(CollectionChangeCallback cb);
+    void add_notification_callback(CollectionChangeCallback cb, size_t token);
+    void remove_notification_callback(size_t token);
+    void remove_all_notification_callbacks();
     
     bool wants_background_updates() const { return m_wants_background_updates; }