feat(socket): add SocketServer and Socket.write

src/core/reload.cpp

@@ -75,3 +75,13 @@ QObject* Reloadable::getChildByReloadId(QObject* parent, const QString& reloadId
 
 	return nullptr;
 }
+
+void PostReloadHook::postReloadTree(QObject* root) {
+	for (auto* child: root->children()) {
+		PostReloadHook::postReloadTree(child);
+	}
+
+	if (auto* self = dynamic_cast<PostReloadHook*>(root)) {
+		self->onPostReload();
+	}
+}

src/core/reload.hpp

@@ -111,3 +111,18 @@ private:
 
 	QList<QObject*> mChildren;
 };
+
+/// Hook that runs after the old widget tree is dropped during a reload.
+class PostReloadHook {
+public:
+	PostReloadHook() = default;
+	virtual ~PostReloadHook() = default;
+	PostReloadHook(PostReloadHook&&) = default;
+	PostReloadHook(const PostReloadHook&) = default;
+	PostReloadHook& operator=(PostReloadHook&&) = default;
+	PostReloadHook& operator=(const PostReloadHook&) = default;
+
+	virtual void onPostReload() = 0;
+
+	static void postReloadTree(QObject* root);
+};

src/core/rootwrapper.cpp

@@ -7,8 +7,10 @@
 #include <qobject.h>
 #include <qqmlcomponent.h>
 #include <qqmlengine.h>
+#include <qtimer.h>
 #include <qurl.h>
 
+#include "reload.hpp"
 #include "shell.hpp"
 #include "watcher.hpp"
 
@@ -48,14 +50,21 @@ void RootWrapper::reloadGraph(bool hard) {
 
 	component.completeCreate();
 
-	newRoot->onReload(hard ? nullptr : this->root);
+	auto* oldRoot = this->root;
+	this->root = newRoot;
 
-	if (this->root != nullptr) {
-		this->root->deleteLater();
-		this->root = nullptr;
+	this->root->onReload(hard ? nullptr : oldRoot);
+
+	if (oldRoot != nullptr) {
+		oldRoot->deleteLater();
+
+		QTimer::singleShot(0, [this, newRoot]() {
+			if (this->root == newRoot) PostReloadHook::postReloadTree(this->root);
+		});
+	} else {
+		PostReloadHook::postReloadTree(newRoot);
 	}
 
-	this->root = newRoot;
 	this->onConfigChanged();
 }
 

src/core/socket.cpp

@@ -1,19 +1,24 @@
 #include "socket.hpp"
 #include <utility>
 
+#include <qfile.h>
+#include <qlocalserver.h>
 #include <qlocalsocket.h>
+#include <qlogging.h>
 #include <qobject.h>
+#include <qqmlcomponent.h>
+#include <qqmlengine.h>
 #include <qtmetamacros.h>
 
 #include "datastream.hpp"
 
 void Socket::setSocket(QLocalSocket* socket) {
 	if (this->socket != nullptr) this->socket->deleteLater();
-
 	this->socket = socket;
-	socket->setParent(this);
 
 	if (socket != nullptr) {
+		socket->setParent(this);
+
 		// clang-format off
 		QObject::connect(this->socket, &QLocalSocket::connected, this, &Socket::onSocketConnected);
 		QObject::connect(this->socket, &QLocalSocket::disconnected, this, &Socket::onSocketDisconnected);
@@ -75,3 +80,120 @@ void Socket::connectPathSocket() {
 		this->socket->connectToServer(QIODevice::ReadWrite);
 	}
 }
+
+void Socket::write(const QString& data) {
+	if (this->socket != nullptr) {
+		this->socket->write(data.toUtf8());
+	}
+}
+
+SocketServer::~SocketServer() { this->disableServer(); }
+
+void SocketServer::onPostReload() {
+	this->postReload = true;
+	if (this->isActivatable()) this->enableServer();
+}
+
+bool SocketServer::isActive() const { return this->server != nullptr; }
+
+void SocketServer::setActive(bool active) {
+	this->activeTarget = active;
+	if (active == (this->server != nullptr)) return;
+
+	if (active) {
+		if (this->isActivatable()) this->enableServer();
+	} else this->disableServer();
+}
+
+QString SocketServer::path() const { return this->mPath; }
+
+void SocketServer::setPath(QString path) {
+	if (this->mPath == path) return;
+	this->mPath = std::move(path);
+	emit this->pathChanged();
+
+	if (this->isActivatable()) this->enableServer();
+}
+
+QQmlComponent* SocketServer::handler() const { return this->mHandler; }
+
+void SocketServer::setHandler(QQmlComponent* handler) {
+	if (this->mHandler != nullptr) this->mHandler->deleteLater();
+	this->mHandler = handler;
+
+	if (handler != nullptr) {
+		handler->setParent(this);
+	}
+}
+
+bool SocketServer::isActivatable() {
+	return this->server == nullptr && this->postReload && this->activeTarget && !this->mPath.isEmpty()
+	    && this->handler() != nullptr;
+}
+
+void SocketServer::enableServer() {
+	this->disableServer();
+
+	this->server = new QLocalServer(this);
+	QObject::connect(
+	    this->server,
+	    &QLocalServer::newConnection,
+	    this,
+	    &SocketServer::onNewConnection
+	);
+
+	if (!this->server->listen(this->mPath)) {
+		qWarning() << "could not start socket server at" << this->mPath;
+		this->disableServer();
+	}
+
+	this->activeTarget = false;
+	emit this->activeStatusChanged();
+}
+
+void SocketServer::disableServer() {
+	auto wasActive = this->server != nullptr;
+
+	if (this->server != nullptr) {
+		for (auto* socket: this->mSockets) {
+			socket->deleteLater();
+		}
+
+		this->mSockets.clear();
+		this->server->deleteLater();
+		this->server = nullptr;
+	}
+
+	if (this->mPath != nullptr) {
+		if (QFile::exists(this->mPath) && !QFile::remove(this->mPath)) {
+			qWarning() << "failed to delete socket file at" << this->mPath;
+		}
+	}
+
+	if (wasActive) emit this->activeStatusChanged();
+}
+
+void SocketServer::onNewConnection() {
+	if (auto* connection = this->server->nextPendingConnection()) {
+		auto* instanceObj = this->mHandler->create(QQmlEngine::contextForObject(this));
+		auto* instance = qobject_cast<Socket*>(instanceObj);
+
+		if (instance == nullptr) {
+			qWarning() << "SocketServer.handler does not create a Socket. Dropping connection.";
+			if (instanceObj != nullptr) instanceObj->deleteLater();
+			connection->deleteLater();
+			return;
+		}
+
+		this->mSockets.append(instance);
+		instance->setParent(this);
+
+		if (instance->isConnected()) {
+			qWarning() << "SocketServer.handler created a socket with an existing connection. Dropping "
+			              "new connection.";
+			connection->deleteLater();
+		} else {
+			instance->setSocket(connection);
+		}
+	}
+}

src/core/socket.hpp

@@ -1,10 +1,15 @@
 #pragma once
 
+#include <qlocalserver.h>
 #include <qlocalsocket.h>
 #include <qobject.h>
+#include <qqmlcomponent.h>
+#include <qqmlintegration.h>
+#include <qtclasshelpermacros.h>
 #include <qtmetamacros.h>
 
 #include "datastream.hpp"
+#include "reload.hpp"
 
 ///! Unix socket listener.
 class Socket: public DataStream {
@@ -24,6 +29,9 @@ class Socket: public DataStream {
 public:
 	explicit Socket(QObject* parent = nullptr): DataStream(parent) {}
 
+	/// Write data to the socket. Does nothing if not connected.
+	Q_INVOKABLE void write(const QString& data);
+
 	// takes ownership
 	void setSocket(QLocalSocket* socket);
 
@@ -56,3 +64,80 @@ private:
 	bool targetConnected = false;
 	QString mPath;
 };
+
+///! Unix socket server.
+/// #### Example
+/// ```qml
+/// SocketServer {
+///   active: true
+///   path: "/path/too/socket.sock"
+///   handler: Socket {
+///     onConnectedChanged: {
+///       console.log(connected ? "new connection!" : "connection dropped!")
+///     }
+///     parser: SplitParser {
+///       onRead: message => console.log(`read message from socket: ${message}`)
+///     }
+///   }
+/// }
+/// ```
+class SocketServer
+    : public QObject
+    , public PostReloadHook {
+	Q_OBJECT;
+	/// If the socket server is currently active. Defaults to false.
+	///
+	/// Setting this to false will destory all active connections and delete
+	/// the socket file on disk.
+	///
+	/// If path is empty setting this property will have no effect.
+	Q_PROPERTY(bool active READ isActive WRITE setActive NOTIFY activeStatusChanged);
+	/// The path to create the socket server at.
+	///
+	/// Setting this property while the server is active will have no effect.
+	Q_PROPERTY(QString path READ path WRITE setPath NOTIFY pathChanged);
+	/// Connection handler component. Must creeate a `Socket`.
+	///
+	/// The created socket should not set `connected` or `path` or the incoming
+	/// socket connection will be dropped (they will be set by the socket server.)
+	/// Setting `connected` to false on the created socket after connection will
+	/// close and delete it.
+	Q_PROPERTY(QQmlComponent* handler READ handler WRITE setHandler NOTIFY handlerChanged);
+	QML_ELEMENT;
+
+public:
+	explicit SocketServer(QObject* parent = nullptr): QObject(parent) {}
+	~SocketServer() override;
+	Q_DISABLE_COPY_MOVE(SocketServer);
+
+	void onPostReload() override;
+
+	[[nodiscard]] bool isActive() const;
+	void setActive(bool active);
+
+	[[nodiscard]] QString path() const;
+	void setPath(QString path);
+
+	[[nodiscard]] QQmlComponent* handler() const;
+	void setHandler(QQmlComponent* handler);
+
+signals:
+	void activeStatusChanged();
+	void pathChanged();
+	void handlerChanged();
+
+private slots:
+	void onNewConnection();
+
+private:
+	bool isActivatable();
+	void enableServer();
+	void disableServer();
+
+	QLocalServer* server = nullptr;
+	QQmlComponent* mHandler = nullptr;
+	QList<Socket*> mSockets;
+	bool activeTarget = false;
+	bool postReload = false;
+	QString mPath;
+};