android debugger looper fixes

lib/browser/rpc.js

@@ -212,6 +212,8 @@ function makeRequest(url, data) {
     return JSON.parse(responseText);
 }
 
+let pollTimeoutId;
+
 //returns an object from rpc serialized json value
 function deserialize_json_value(value) {
     let result = {};
@@ -230,17 +232,19 @@ function deserialize_json_value(value) {
 }
 
 function sendRequest(command, data, host = sessionHost) {
-    if (!host) {
-        throw new Error('Must first create RPC session with a valid host');
-    }
+    clearTimeout(pollTimeoutId);
+    try {
+        if (!host) {
+            throw new Error('Must first create RPC session with a valid host');
+        }
 
-    data = Object.assign({}, data, sessionId ? {sessionId} : null);
+        data = Object.assign({}, data, sessionId ? {sessionId} : null);
 
-    let url = 'http://' + host + '/' + command;
-    let response = makeRequest(url, data);
+        let url = 'http://' + host + '/' + command;
+        let response = makeRequest(url, data);
 
-    if (!response || response.error) {
-        let error = response && response.error;
+        if (!response || response.error) {
+            let error = response && response.error;
 
         // Remove the type prefix from the error message (e.g. "Error: ").
         if (error && error.replace) {
@@ -261,22 +265,25 @@ function sendRequest(command, data, host = sessionHost) {
 
         throw new Error(error || `Invalid response for "${command}"`);
     }
-
-    let callback = response.callback;
-    if (callback != null) {
-        let result;
-        let error;
-        try {
-            let realmId = data.realmId;
-            let thisObject = deserialize(realmId, response.this);
-            let args = deserialize(realmId, response.arguments);
-            result = registeredCallbacks[callback].apply(thisObject, args);
-            result = serialize(realmId, result);
-        } catch (e) {
-            error = e.message || ('' + e);
+        let callback = response.callback;
+        if (callback != null) {
+            let result;
+            let error;
+            try {
+                let realmId = data.realmId;
+                let thisObject = deserialize(realmId, response.this);
+                let args = deserialize(realmId, response.arguments);
+                result = registeredCallbacks[callback].apply(thisObject, args);
+                result = serialize(realmId, result);
+            } catch (e) {
+                error = e.message || ('' + e);
+            }
+            return sendRequest('callback_result', {callback, result, error});
         }
-        return sendRequest('callback_result', {callback, result, error});
-    }
 
-    return response.result;
+        return response.result;
+    }
+    finally {
+        pollTimeoutId = setTimeout(() => sendRequest('callbacks_poll'), 50);
+    }
 }

react-native/android/src/main/java/io/realm/react/RealmReactModule.java

@@ -2,6 +2,9 @@ package io.realm.react;
 
 import android.content.res.AssetManager;
 import android.os.Build;
+import android.os.Handler;
+import android.os.HandlerThread;
+import android.os.Looper;
 import android.util.Log;
 
 import com.facebook.react.bridge.ReactApplicationContext;
@@ -19,6 +22,9 @@ import java.util.Enumeration;
 import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
+import java.util.concurrent.ExecutionException;
+import java.util.concurrent.FutureTask;
+import java.util.concurrent.RunnableFuture;
 
 import fi.iki.elonen.NanoHTTPD;
 
@@ -37,6 +43,9 @@ class RealmReactModule extends ReactContextBaseJavaModule {
         SoLoader.loadLibrary("realmreact");
     }
 
+    private Handler worker;
+    private HandlerThread workerThread;
+
     public RealmReactModule(ReactApplicationContext reactContext) {
         super(reactContext);
 
@@ -121,7 +130,9 @@ class RealmReactModule extends ReactContextBaseJavaModule {
 
     private void startWebServer() {
         setupChromeDebugModeRealmJsContext();
-        webServer = new AndroidWebServer(DEFAULT_PORT);
+        startWorker();
+
+        webServer = new AndroidWebServer(DEFAULT_PORT, getReactApplicationContext());
         try {
             webServer.start();
             Log.i("Realm", "Starting the debugging WebServer, Host: " + webServer.getHostname() + " Port: " + webServer.getListeningPort());
@@ -130,20 +141,44 @@ class RealmReactModule extends ReactContextBaseJavaModule {
         }
     }
 
+    private void startWorker() {
+        workerThread = new HandlerThread("MyHandlerThread");
+        workerThread.start();
+        worker = new Handler(workerThread.getLooper());
+        worker.postDelayed(new Runnable() {
+            @Override
+            public void run() {
+                boolean stop = tryRunTask();
+                if (!stop) {
+                    worker.postDelayed(this, 10);
+                }
+            }
+        }, 10);
+    }
+
     private void stopWebServer() {
         if (webServer != null) {
              Log.i("Realm", "Stopping the webserver");
              webServer.stop();
         }
+
+        if (workerThread != null) {
+            workerThread.quit();
+            workerThread = null;
+        }
     }
 
     class AndroidWebServer extends NanoHTTPD {
-        public AndroidWebServer(int port) {
+        private ReactApplicationContext reactApplicationContext;
+
+        public AndroidWebServer(int port, ReactApplicationContext reactApplicationContext) {
             super(port);
+            this.reactApplicationContext = reactApplicationContext;
         }
 
-        public AndroidWebServer(String hostname, int port) {
+        public AndroidWebServer(String hostname, int port, ReactApplicationContext reactApplicationContext) {
             super(hostname, port);
+            this.reactApplicationContext = reactApplicationContext;
         }
 
         @Override
@@ -164,7 +199,7 @@ class RealmReactModule extends ReactContextBaseJavaModule {
                 return response;
             }  
             final String jsonResponse = processChromeDebugCommand(cmdUri, json);
-
+           
             Response response = newFixedLengthResponse(jsonResponse);
             response.addHeader("Access-Control-Allow-Origin", "http://localhost:8081");
             return response;
@@ -185,4 +220,7 @@ class RealmReactModule extends ReactContextBaseJavaModule {
 
     // this receives one command from Chrome debug then return the processing we should post back
     private native String processChromeDebugCommand(String cmd, String args);
+
+    // this receives one command from Chrome debug then return the processing we should post back
+    private native boolean tryRunTask();
 }

src/android/io_realm_react_RealmReactModule.cpp

@@ -77,6 +77,13 @@ JNIEXPORT jstring JNICALL Java_io_realm_react_RealmReactModule_processChromeDebu
     return env->NewStringUTF(response.dump().c_str());
 }
 
+JNIEXPORT jboolean JNICALL Java_io_realm_react_RealmReactModule_tryRunTask
+(JNIEnv *env, jclass)
+{
+  jboolean result = s_rpc_server->try_run_task();
+  return result;
+}
+
 JNIEXPORT jboolean JNICALL Java_io_realm_react_RealmReactModule_isContextInjected
     (JNIEnv *env, jclass)
 {

src/android/io_realm_react_RealmReactModule.h

@@ -29,6 +29,13 @@ JNIEXPORT jlong JNICALL Java_io_realm_react_RealmReactModule_setupChromeDebugMod
 JNIEXPORT jstring JNICALL Java_io_realm_react_RealmReactModule_processChromeDebugCommand
   (JNIEnv *, jclass, jstring, jstring);
 
+/*
+ * Class:     io_realm_react_RealmReactModule
+ * Method:    tryRunTask
+ */
+JNIEXPORT jboolean JNICALL Java_io_realm_react_RealmReactModule_tryRunTask
+(JNIEnv *, jclass);
+
 /*
  * Class:     io_realm_react_RealmReactModule
  * Method:    isContextInjected

src/js_realm.hpp

@@ -738,6 +738,7 @@ void RealmClass<T>::wait_for_download_completion(ContextType ctx, ObjectType thi
 
                 ValueType callback_arguments[1];
                 callback_arguments[0] = object;
+                
                 Function<T>::callback(protected_ctx, protected_callback, protected_this, 1, callback_arguments);
             }
 

src/rpc.cpp

@@ -28,6 +28,7 @@
 #include "object_accessor.hpp"
 #include "shared_realm.hpp"
 #include "results.hpp"
+#include <android/looper.h>
 
 using namespace realm;
 using namespace realm::rpc;
@@ -83,12 +84,14 @@ RPCServer*& get_rpc_server(JSGlobalContextRef ctx) {
 }
 
 RPCWorker::RPCWorker() {
-    m_thread = std::thread([this]() {
+    //m_thread = std::thread([this]() {
+        //m_looper = ALooper_prepare(ALOOPER_PREPARE_ALLOW_NON_CALLBACKS);
+
         // TODO: Create ALooper/CFRunLoop to support async calls.
-        while (!m_stop) {
-            try_run_task();
-        }
-    });
+        //while (!m_stop) {
+            //try_run_task();
+        //}
+    //});
 }
 
 RPCWorker::~RPCWorker() {
@@ -107,23 +110,30 @@ json RPCWorker::pop_task_result() {
     return future.get();
 }
 
-void RPCWorker::try_run_task() {
+bool RPCWorker::try_run_task() {
+    if (m_stop) {
+        return true;
+    }
+
     // Use a 10 millisecond timeout to keep this thread unblocked.
     auto task = m_tasks.try_pop_back(10);
     if (!task) {
-        return;
+        return false;
     }
 
     (*task)();
 
     // Since this can be called recursively, it must be pushed to the front of the queue *after* running the task.
     m_futures.push_front(task->get_future());
+
+    return m_stop;
 }
 
 void RPCWorker::stop() {
     if (!m_stop) {
         m_stop = true;
         m_thread.join();
+        //m_looper = nullptr;
     }
 }
 
@@ -288,6 +298,10 @@ RPCServer::RPCServer() {
 
         return json::object();
     };
+
+    m_requests["/callbacks_poll"] = [this](const json dict) {
+        return json::object();
+    };
 }
 
 RPCServer::~RPCServer() {
@@ -340,6 +354,7 @@ void RPCServer::run_callback(JSContextRef ctx, JSObjectRef function, JSObjectRef
     }
 
     return_value.set(server->deserialize_json_value(results["result"]));
+
 }
 
 json RPCServer::perform_request(std::string name, const json &args) {
@@ -388,6 +403,10 @@ json RPCServer::perform_request(std::string name, const json &args) {
     }
 }
 
+bool RPCServer::try_run_task() {
+    return m_worker.try_run_task();
+}
+
 RPCObjectID RPCServer::store_object(JSObjectRef object) {
     static RPCObjectID s_next_id = 1;
 

src/rpc.hpp

@@ -26,6 +26,7 @@
 #include "json.hpp"
 #include "jsc_types.hpp"
 #include "jsc_protected.hpp"
+#include <android/looper.h>
 
 namespace realm {
 
@@ -45,11 +46,12 @@ class RPCWorker {
 
     void add_task(std::function<json()>);
     json pop_task_result();
-    void try_run_task();
+    bool try_run_task();
     void stop();
 
   private:
     bool m_stop = false;
+    //ALooper* m_looper;
     std::thread m_thread;
     ConcurrentDeque<std::packaged_task<json()>> m_tasks;
     ConcurrentDeque<std::future<json>> m_futures;
@@ -60,6 +62,7 @@ class RPCServer {
     RPCServer();
     ~RPCServer();
     json perform_request(std::string name, const json &args);
+    bool try_run_task();
 
   private:
     JSGlobalContextRef m_context;