Qt Quick UI for the RESTful Address Book

Add UI and client side extension for the RESTful Address Book example

Fixes: QTBUG-105199
Change-Id: I01c5e2ac44838f01ccbb73d5b6e1d1e578c67618
Reviewed-by: Qt CI Bot <qt_ci_bot@qt-project.org>
Reviewed-by: Alex Blasche <alexander.blasche@qt.io>
(cherry picked from commit 91e567ba53bf8c7be9aff8feb00e46f978937290)
Reviewed-by: Mårten Nordheim <marten.nordheim@qt.io>

12 files changed, 715 insertions, 0 deletions

diff --git a/examples/demos/addressbook/CMakeLists.txt b/examples/demos/addressbook/CMakeLists.txt
new file mode 100644
index 000000000..7572f4dc8
--- /dev/null
+++ b/examples/demos/addressbook/CMakeLists.txt
@@ -0,0 +1,58 @@
+# Copyright (C) 2022 The Qt Company Ltd.
+# SPDX-License-Identifier: LicenseRef-Qt-Commercial OR BSD-3-Clause
+
+cmake_minimum_required(VERSION 3.16)
+project(addressbookclient LANGUAGES CXX)
+
+set(CMAKE_AUTOMOC ON)
+
+if(NOT DEFINED INSTALL_EXAMPLESDIR)
+    set(INSTALL_EXAMPLESDIR "examples")
+endif()
+
+set(INSTALL_EXAMPLEDIR "${INSTALL_EXAMPLESDIR}/demos/${PROJECT_NAME}")
+
+find_package(Qt6 REQUIRED COMPONENTS Core Gui Qml Quick)
+
+qt_add_executable(addressbookclient
+    addressbookmodel.h addressbookmodel.cpp
+    restaccessmanager.h restaccessmanager.cpp
+    main.cpp
+)
+
+set(qml_files
+    "qml/main.qml"
+)
+
+qt_add_resources(addressbookclient "qml"
+    PREFIX
+        "/"
+    FILES
+        ${qml_files}
+)
+
+set_target_properties(addressbookclient PROPERTIES
+    WIN32_EXECUTABLE TRUE
+    MACOSX_BUNDLE TRUE
+)
+
+qt_add_qml_module(addressbookclient
+    URI AddressBookModel
+    VERSION 1.0
+    QML_FILES
+        "qml/main.qml"
+    NO_RESOURCE_TARGET_PATH
+)
+
+target_link_libraries(addressbookclient PRIVATE
+    Qt::Core
+    Qt::Gui
+    Qt::Qml
+    Qt::Quick
+)
+
+install(TARGETS addressbookclient
+    RUNTIME DESTINATION "${INSTALL_EXAMPLEDIR}"
+    BUNDLE DESTINATION "${INSTALL_EXAMPLEDIR}"
+    LIBRARY DESTINATION "${INSTALL_EXAMPLEDIR}"
+)
diff --git a/examples/demos/addressbook/addressbookmodel.cpp b/examples/demos/addressbook/addressbookmodel.cpp
new file mode 100644
index 000000000..83422964f
--- /dev/null
+++ b/examples/demos/addressbook/addressbookmodel.cpp
@@ -0,0 +1,127 @@
+// Copyright (C) 2022 The Qt Company Ltd.
+// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR BSD-3-Clause
+
+#include "addressbookmodel.h"
+#include "contactentry.h"
+
+#include <QMutexLocker>
+
+AddressBookModel::AddressBookModel(QSharedPointer<RestAccessManager> manager, QObject *parent)
+    : QAbstractTableModel(parent), accessManager(std::move(manager))
+{
+    QObject::connect(accessManager.get(), &RestAccessManager::contactsChanged, this,
+                     &AddressBookModel::updateContacts);
+}
+
+AddressBookModel::~AddressBookModel() = default;
+
+int AddressBookModel::rowCount(const QModelIndex &parent) const
+{
+    if (parent.isValid())
+        return 0;
+
+    QMutexLocker lock(&contactsMtx);
+    return contacts.size();
+}
+
+int AddressBookModel::columnCount(const QModelIndex &parent) const
+{
+    if (parent.isValid())
+        return 0;
+
+    return ContactEntry::size();
+}
+
+QVariant AddressBookModel::headerData(int section, Qt::Orientation orientation, int role) const
+{
+    if (orientation == Qt::Orientation::Horizontal) {
+        switch (section) {
+        case 0:
+            return ""; // ID is not shown
+        case 1:
+            return "Name";
+        case 2:
+            return "Address";
+        }
+    }
+    return QVariant();
+}
+
+QVariant AddressBookModel::data(const QModelIndex &index, int role) const
+{
+    QMutexLocker lock(&contactsMtx);
+
+    if (index.row() < 0 || index.row() >= contacts.count())
+        return QVariant();
+
+    const ContactEntry &contact = contacts.at(index.row());
+    QVariant ret;
+
+    switch (role) {
+    case AddressBookRoles::IdRole:
+        ret = contact.id;
+        break;
+
+    case AddressBookRoles::NameRole:
+        ret = contact.name;
+        break;
+
+    case AddressBookRoles::AddressRole:
+        ret = contact.address;
+        break;
+    }
+    return ret;
+}
+
+QHash<int, QByteArray> AddressBookModel::roleNames() const
+{
+    QHash<int, QByteArray> roles;
+    roles[AddressBookRoles::IdRole] = "id";
+    roles[AddressBookRoles::NameRole] = "name";
+    roles[AddressBookRoles::AddressRole] = "address";
+    return roles;
+}
+
+Q_INVOKABLE void AddressBookModel::setAuthorizationHeader(const QString &key, const QString &value)
+{
+    accessManager->setAuthorizationHeader(key, value);
+}
+
+Q_INVOKABLE void AddressBookModel::addContact(const QString &name, const QString &contact)
+{
+    accessManager->addContact(ContactEntry{ 0, name, contact });
+}
+
+Q_INVOKABLE void AddressBookModel::updateContact(qint64 id, const QString &name,
+                                                 const QString &contact)
+{
+    accessManager->updateContact(ContactEntry{ id, name, contact });
+}
+
+Q_INVOKABLE void AddressBookModel::removeContact(const qint64 id)
+{
+    accessManager->deleteContact(id);
+}
+
+Q_INVOKABLE void AddressBookModel::refresh()
+{
+    this->updateContacts();
+}
+
+void AddressBookModel::updateContacts()
+{
+    auto toContactEntry = [](const auto &it) {
+        return ContactEntry{ it.first, it.second.name, it.second.address };
+    };
+    QList<ContactEntry> tmpContacts;
+    const RestAccessManager::ContactsMap contactsMap = accessManager->getContacts();
+    std::transform(contactsMap.constKeyValueBegin(), contactsMap.constKeyValueEnd(),
+                   std::back_inserter(contacts), toContactEntry);
+
+    this->beginInsertRows(this->index(-1, -1), 0, this->rowCount());
+    {
+        QMutexLocker lock(&contactsMtx);
+        contacts.swap(tmpContacts);
+    }
+    this->endInsertRows();
+}
diff --git a/examples/demos/addressbook/addressbookmodel.h b/examples/demos/addressbook/addressbookmodel.h
new file mode 100644
index 000000000..e7b8d6027
--- /dev/null
+++ b/examples/demos/addressbook/addressbookmodel.h
@@ -0,0 +1,50 @@
+// Copyright (C) 2022 The Qt Company Ltd.
+// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR BSD-3-Clause
+
+#ifndef ADDRESSBOOKMODEL_H
+#define ADDRESSBOOKMODEL_H
+
+#include "contactentry.h"
+#include "restaccessmanager.h"
+
+#include <QAbstractItemModel>
+#include <QMutex>
+#include <QSharedPointer>
+#include <QtQml/qqml.h>
+
+class AddressBookModel : public QAbstractTableModel
+{
+    Q_OBJECT
+    QML_ELEMENT
+public:
+    enum AddressBookRoles { IdRole = Qt::UserRole + 1, NameRole, AddressRole };
+    Q_ENUM(AddressBookRoles)
+
+    explicit AddressBookModel(QSharedPointer<RestAccessManager> manager, QObject *parent = nullptr);
+    ~AddressBookModel();
+
+    int rowCount(const QModelIndex &parent = QModelIndex()) const override;
+    int columnCount(const QModelIndex &parent = QModelIndex()) const override;
+    QVariant headerData(int section, Qt::Orientation orientation, int role) const override;
+    QVariant data(const QModelIndex &index, int role = Qt::DisplayRole) const override;
+    QHash<int, QByteArray> roleNames() const override;
+
+    Q_INVOKABLE void setAuthorizationHeader(const QString &key, const QString &value);
+    Q_INVOKABLE void addContact(const QString &name, const QString &contact);
+    Q_INVOKABLE void updateContact(qint64 id, const QString &name, const QString &contact);
+    Q_INVOKABLE void removeContact(qint64 id);
+    Q_INVOKABLE void refresh();
+
+signals:
+    void contactsChanged();
+
+private slots:
+    void updateContacts();
+
+private:
+    QSharedPointer<RestAccessManager> accessManager;
+    mutable QMutex contactsMtx;
+    QList<ContactEntry> contacts;
+};
+
+#endif // ADDRESSBOOKMODEL_H
diff --git a/examples/demos/addressbook/contactentry.h b/examples/demos/addressbook/contactentry.h
new file mode 100644
index 000000000..e70e629fa
--- /dev/null
+++ b/examples/demos/addressbook/contactentry.h
@@ -0,0 +1,29 @@
+// Copyright (C) 2022 The Qt Company Ltd.
+// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR BSD-3-Clause
+
+#ifndef TYPES_H
+#define TYPES_H
+
+#include <QJsonObject>
+#include <QString>
+
+struct ContactEntry
+{
+    qint64 id;
+    QString name;
+    QString address;
+
+    QJsonObject toJson() const
+    {
+        return QJsonObject{ { "id", id }, { "name", name }, { "address", address } };
+    }
+
+    static constexpr qsizetype size() { return 3; }
+
+    bool operator==(const ContactEntry &other) const
+    {
+        return name == other.name && address == other.address;
+    }
+};
+
+#endif // TYPES_H
diff --git a/examples/demos/addressbook/doc/images/addressbookclient.png b/examples/demos/addressbook/doc/images/addressbookclient.png
new file mode 100644
index 000000000..9ed284464
--- /dev/null
+++ b/examples/demos/addressbook/doc/images/addressbookclient.png
diff --git a/examples/demos/addressbook/doc/images/authorize.png b/examples/demos/addressbook/doc/images/authorize.png
new file mode 100644
index 000000000..16ad5e709
--- /dev/null
+++ b/examples/demos/addressbook/doc/images/authorize.png
diff --git a/examples/demos/addressbook/doc/images/newcontact.png b/examples/demos/addressbook/doc/images/newcontact.png
new file mode 100644
index 000000000..df351c371
--- /dev/null
+++ b/examples/demos/addressbook/doc/images/newcontact.png
diff --git a/examples/demos/addressbook/doc/src/addressbook-client-example.qdoc b/examples/demos/addressbook/doc/src/addressbook-client-example.qdoc
new file mode 100644
index 000000000..23bcfe37f
--- /dev/null
+++ b/examples/demos/addressbook/doc/src/addressbook-client-example.qdoc
@@ -0,0 +1,70 @@
+// Copyright (C) 2022 The Qt Company Ltd.
+// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR GFDL-1.3-no-invariants-only
+
+/*!
+\ingroup qtquickdemos
+\example demos/addressbook
+\title Qt Quick Demo - RESTful API client Address Book
+\brief Example of how to create a RESTful API client.
+\image addressbookclient.png
+
+This example shows how to create a basic QML application with address book
+functionality.
+The application uses RESTful communication with a given server to send
+requests and retrieve data.
+
+The application allows users to add new contacts by clicking the
+'Add Contact' button and then entering the data for the record and
+clicking the 'Add' button (see image below).
+\image newcontact.png
+
+The Address Book application gives you the ability to delete an entry,
+by clicking the 'Delete' button next to the entry, and update by updating
+the data in the table.
+
+In order to use the modification features, users must authorize themselves
+by providing a key and value, which will be used in communication
+with the RESTful API.
+\image authorize.png
+
+To run the client application, first run the
+\l {RESTful server Address Book Example} {Address Book server example}
+in the background or use an already running server that provides used API.
+Then run the client application, to run it host and port arguments must be provided,
+for example:
+\code
+./addressbookclient  --host http://127.0.0.1 --port 62122
+\endcode
+
+This example application uses QNetworkAccessManager
+which is wrapped in the \c RestAccessManager class.
+
+\snippet demos/addressbook/restaccessmanager.cpp Connect QNetworkAccessManager example
+The code snippet above shows how to connect QNetworkAccessManager to this wrapper.
+First, a connection to the server is established
+and the QNetworkAccessManager::setAutoDeleteReplies method is called to simplify
+the QNetworkReply deletion.
+Then QObject::connect is used to call the internal \c RestAccessManager::readContacts
+after the QNetworkReply is ready to be processed.
+
+\snippet demos/addressbook/restaccessmanager.cpp Update contacts signal example
+This method asynchronously processes each QNetworkReply
+for each request sent via QNetworkAccessManager.
+When the response is an array, that practically means that RestAccessManage
+got a new list of the contacts, so it has to update it.
+When the response is different, it means that the corresponding request
+has changed the list of contacts and it needs to be retrieved from the server.
+
+\snippet demos/addressbook/restaccessmanager.cpp GET contacts example
+To send a \c GET request, the QNetworkAccessManager::get method is used
+with the prepared QNetworkRequest.
+QNetworkRequest::setHeader is used to ensure correct encoding of the content.
+
+\snippet demos/addressbook/restaccessmanager.cpp POST contacts example
+To send the \c POST request, a similar approach can be used.
+In addition, to set the authorization header
+QNetworkRequest::setRawHeader was used.
+
+
+\sa {RESTful server Address Book Example}
+*/
diff --git a/examples/demos/addressbook/main.cpp b/examples/demos/addressbook/main.cpp
new file mode 100644
index 000000000..f419e5b36
--- /dev/null
+++ b/examples/demos/addressbook/main.cpp
@@ -0,0 +1,38 @@
+// Copyright (C) 2022 The Qt Company Ltd.
+// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR BSD-3-Clause
+
+#include "addressbookmodel.h"
+#include "restaccessmanager.h"
+
+#include <QCommandLineParser>
+#include <QGuiApplication>
+#include <QQmlApplicationEngine>
+#include <QQmlContext>
+
+int main(int argc, char *argv[])
+{
+    QGuiApplication app(argc, argv);
+
+    QCommandLineParser parser;
+    parser.addOptions({
+            { "host", QCoreApplication::translate("main", "Hostname of the server."), "host" },
+            { "port", QCoreApplication::translate("main", "Port of the server."), "port" },
+    });
+    parser.addHelpOption();
+    parser.process(app);
+
+    if (parser.value("host").isEmpty() || parser.value("port").isEmpty())
+        parser.showHelp(-1);
+
+    QQmlApplicationEngine engine;
+    auto manager = QSharedPointer<RestAccessManager>::create(parser.value("host"),
+                                                             parser.value("port").toInt());
+    AddressBookModel model(manager);
+    engine.setInitialProperties({ { "addressBookModel", QVariant::fromValue(&model) } });
+
+    engine.load(QUrl("qrc:/qml/main.qml"));
+    if (engine.rootObjects().isEmpty())
+        return -1;
+
+    return QGuiApplication::exec();
+}
diff --git a/examples/demos/addressbook/qml/main.qml b/examples/demos/addressbook/qml/main.qml
new file mode 100644
index 000000000..2505cd40b
--- /dev/null
+++ b/examples/demos/addressbook/qml/main.qml
@@ -0,0 +1,173 @@
+// Copyright (C) 2022 The Qt Company Ltd.
+// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR BSD-3-Clause
+import QtQuick
+import QtQuick.Controls
+import QtQuick.Layouts
+import QtQuick.Window
+import Qt.labs.qmlmodels
+
+import AddressBookModel
+
+ApplicationWindow {
+    id: root
+    width: 850
+    height: 350
+    visible: true
+    title: qsTr("Address Book")
+    required property AddressBookModel addressBookModel
+
+    Button {
+        id: newContactButton
+        text: qsTr("Add new contact")
+        onClicked: newContactPopup.open()
+    }
+    Popup {
+        id: newContactPopup
+        padding: 10
+        anchors.centerIn: parent
+        modal: true
+        focus: true
+
+        closePolicy: Popup.CloseOnEscape | Popup.CloseOnPressOutsideParent
+
+        GridLayout {
+            columns: 2
+            TextField {
+                id: newNameField
+                placeholderText: qsTr("Enter name")
+                padding: 10
+            }
+            TextField {
+                id: newAddressField
+                placeholderText: qsTr("Enter address")
+                padding: 10
+            }
+            Button {
+                text: qsTr("Cancel")
+                onClicked: {
+                    newContactPopup.close();
+                }
+            }
+            Button {
+                text: qsTr("Add")
+                onClicked: {
+                    addressBookModel.addContact(newNameField.displayText,
+                        newAddressField.displayText);
+                    newContactPopup.close();
+                }
+            }
+        }
+    }
+
+    Button {
+        id: authorizeButton
+        text: qsTr("Authorize")
+        onClicked: authorizePopup.open()
+        anchors {
+            top: newContactButton.bottom
+            left: newContactButton.left
+        }
+    }
+    Popup {
+        id: authorizePopup
+        padding: 10
+        anchors.centerIn: parent
+        modal: true
+        focus: true
+
+        closePolicy: Popup.CloseOnEscape | Popup.CloseOnPressOutsideParent
+
+        GridLayout {
+            columns: 2
+            TextField {
+                id: apiKeyField
+                text: "api_key"
+                padding: 10
+                readOnly: true
+            }
+            TextField {
+                id: apiKeyValueField
+                placeholderText: qsTr("Enter API key value")
+                padding: 10
+            }
+            Button {
+                text: qsTr("Cancel")
+                onClicked: {
+                    authorizePopup.close();
+                }
+            }
+            Button {
+                text: qsTr("Set")
+                onClicked: {
+                    addressBookModel.setAuthorizationHeader(apiKeyField.displayText,
+                        apiKeyValueField.displayText);
+                    authorizePopup.close();
+                }
+            }
+        }
+    }
+
+    HorizontalHeaderView {
+        id: horizontalHeader
+        model: addressBookModel
+        syncView: tableView
+        anchors {
+            top: newContactButton.top
+            left: newContactButton.right
+        }
+    }
+
+    TableView {
+        id: tableView
+        model: addressBookModel
+        anchors {
+            top: horizontalHeader.bottom
+            left: horizontalHeader.left
+        }
+        width: 700
+        height: 350
+        columnSpacing: 1
+        rowSpacing: 1
+        clip: true
+        property var columnWidthsFactor: [0.15, 0.35, 0.5]
+        columnWidthProvider: function (column) {
+            return tableView.model ? tableView.width * columnWidthsFactor[column] : 0;
+        }
+        rowHeightProvider: function (row) {
+            return 50;
+        }
+
+        delegate: DelegateChooser {
+            DelegateChoice {
+                column: 0
+                delegate: Rectangle {
+                    Button {
+                        id: deleteButton
+                        text: qsTr("Delete")
+                        onClicked: addressBookModel.removeContact(id)
+                    }
+                }
+            }
+            DelegateChoice {
+                column: 1
+                delegate: Rectangle {
+                    TextInput {
+                        text: name
+                        padding: 10
+                        onEditingFinished: addressBookModel.updateContact(id, displayText, address)
+                    }
+                }
+            }
+            DelegateChoice {
+                column: 2
+                delegate: Rectangle {
+                    TextInput {
+                        text: address
+                        padding: 10
+                        onEditingFinished: addressBookModel.updateContact(id, name, displayText)
+                    }
+                }
+            }
+        }
+    }
+}
diff --git a/examples/demos/addressbook/restaccessmanager.cpp b/examples/demos/addressbook/restaccessmanager.cpp
new file mode 100644
index 000000000..7b746a085
--- /dev/null
+++ b/examples/demos/addressbook/restaccessmanager.cpp
@@ -0,0 +1,114 @@
+// Copyright (C) 2022 The Qt Company Ltd.
+// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR BSD-3-Clause
+
+#include "restaccessmanager.h"
+
+#include <QJsonArray>
+#include <QJsonDocument>
+#include <QNetworkReply>
+
+static std::optional<QJsonArray> byteArrayToJsonArray(const QByteArray &arr)
+{
+    QJsonParseError err;
+    const auto json = QJsonDocument::fromJson(arr, &err);
+    if (err.error || !json.isArray())
+        return std::nullopt;
+    return json.array();
+}
+
+RestAccessManager::RestAccessManager(const QString &host, quint16 port) : host(host), port(port)
+{
+    //! [Connect QNetworkAccessManager example]
+    manager.connectToHost(host, port);
+    manager.setAutoDeleteReplies(true);
+    QObject::connect(&manager, &QNetworkAccessManager::finished, this,
+                     &RestAccessManager::readContacts);
+    //! [Connect QNetworkAccessManager example]
+    this->updateContacts();
+}
+
+RestAccessManager::~RestAccessManager() = default;
+
+void RestAccessManager::setAuthorizationHeader(const QString &key, const QString &value)
+{
+    authHeader = AuthHeader{ key, value };
+}
+
+RestAccessManager::ContactsMap RestAccessManager::getContacts() const
+{
+    QMutexLocker lock(&contactsMtx);
+    return contacts;
+}
+
+//! [POST contacts example]
+void RestAccessManager::addContact(const ContactEntry &entry)
+{
+    auto request = QNetworkRequest(QUrl(QString("%1:%2/v2/contact").arg(host).arg(port)));
+    request.setHeader(QNetworkRequest::KnownHeaders::ContentTypeHeader, "application/json");
+    if (authHeader) {
+        request.setRawHeader(authHeader->key.toLatin1(), authHeader->value.toLatin1());
+    }
+    manager.post(request, QJsonDocument(entry.toJson()).toJson(QJsonDocument::Compact));
+}
+//! [POST contacts example]
+
+void RestAccessManager::updateContact(const ContactEntry &entry)
+{
+    auto request =
+            QNetworkRequest(QUrl(QString("%1:%2/v2/contact/%3").arg(host).arg(port).arg(entry.id)));
+    request.setHeader(QNetworkRequest::KnownHeaders::ContentTypeHeader, "application/json");
+    if (authHeader) {
+        request.setRawHeader(authHeader->key.toLatin1(), authHeader->value.toLatin1());
+    }
+    manager.put(request, QJsonDocument(entry.toJson()).toJson(QJsonDocument::Compact));
+}
+
+void RestAccessManager::deleteContact(qint64 id)
+{
+    auto request =
+            QNetworkRequest(QUrl(QString("%1:%2/v2/contact/%3").arg(host).arg(port).arg(id)));
+    if (authHeader) {
+        request.setRawHeader(authHeader->key.toLatin1(), authHeader->value.toLatin1());
+    }
+    manager.deleteResource(request);
+}
+
+//! [Update contacts signal example]
+void RestAccessManager::readContacts(QNetworkReply *reply)
+{
+    if (reply->error()) {
+        return;
+    }
+    const std::optional<QJsonArray> array = byteArrayToJsonArray(reply->readAll());
+    if (array) {
+        ContactsMap tmpContacts;
+        for (const auto &jsonValue : *array) {
+            if (jsonValue.isObject()) {
+                const QJsonObject obj = jsonValue.toObject();
+                if (obj.contains("id") && obj.contains("name") && obj.contains("address")) {
+                    tmpContacts.insert(obj.value("id").toInt(),
+                                       ContactEntry{ obj.value("id").toInt(),
+                                                     obj.value("name").toString(),
+                                                     obj.value("address").toString() });
+                }
+            }
+        }
+        {
+            QMutexLocker lock(&contactsMtx);
+            contacts.swap(tmpContacts);
+        }
+        emit contactsChanged();
+    } else {
+        this->updateContacts();
+    }
+}
+//! [Update contacts signal example]
+
+//! [GET contacts example]
+void RestAccessManager::updateContacts()
+{
+    auto request = QNetworkRequest(QUrl(QString("%1:%2/v2/contact").arg(host).arg(port)));
+    request.setHeader(QNetworkRequest::KnownHeaders::ContentTypeHeader, "application/json");
+    manager.get(request);
+}
+//! [GET contacts example]
diff --git a/examples/demos/addressbook/restaccessmanager.h b/examples/demos/addressbook/restaccessmanager.h
new file mode 100644
index 000000000..19d417ede
--- /dev/null
+++ b/examples/demos/addressbook/restaccessmanager.h
@@ -0,0 +1,56 @@
+// Copyright (C) 2022 The Qt Company Ltd.
+// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR BSD-3-Clause
+
+#ifndef RESTACCESSMANAGER_H
+#define RESTACCESSMANAGER_H
+
+#include "contactentry.h"
+
+#include <QMap>
+#include <QMutex>
+#include <QNetworkAccessManager>
+#include <QObject>
+#include <QString>
+
+#include <optional>
+
+class RestAccessManager : public QObject
+{
+    Q_OBJECT
+    struct AuthHeader
+    {
+        QString key;
+        QString value;
+    };
+
+public:
+    using ContactsMap = QMap<qint64, ContactEntry>;
+
+    explicit RestAccessManager(const QString &host, quint16 port);
+    ~RestAccessManager();
+
+    void setAuthorizationHeader(const QString &key, const QString &value);
+    ContactsMap getContacts() const;
+
+    void addContact(const ContactEntry &entry);
+    void updateContact(const ContactEntry &entry);
+    void deleteContact(qint64 id);
+
+signals:
+    void contactsChanged();
+
+private slots:
+    void readContacts(QNetworkReply *reply);
+
+private:
+    void updateContacts();
+
+    const QString host;
+    const quint16 port;
+    std::optional<AuthHeader> authHeader;
+    QNetworkAccessManager manager;
+    mutable QMutex contactsMtx;
+    ContactsMap contacts;
+};
+
+#endif // RESTACCESSMANAGER_H