Extensible OPC UA Client
Jan Schlachter, Alexander Franjic, Christoph Wolf, Marius Reddig, Christopher Besch, Marwin
Glaser •
12th Sep 2024
Extensible OPC UA Client
Working Title: Magnesia
Requirements
- Graphical OPC UA Client
- Extensible / Open Source
- Cross-Platform C++
Live Demo
Linux
macOS
Windows
GUI Overview
- Activities as Tabs
- AddActivity
- Settings
- DataViewer
- About
- DataViewer uses Panels
User Docs
Activity Development
// example.hpp //
namespace magnesia::activities::example {
class Example : public Activity {
public:
explicit Example(QWidget* parent = nullptr);
};
// how to create the example tab from the Add Activity
class ConfigWidget : public magnesia::ConfigWidget {
public:
explicit ConfigWidget(QWidget* parent = nullptr);
};
inline constexpr ActivityMetadata metadata{
.name = u"Example",
.create_config_widget = []() -> magnesia::ConfigWidget* {
return new ConfigWidget;
},
};
}
// example.cpp //
namespace magnesia::activities::example {
Example::Example(QWidget* parent) : Activity(parent) {
auto* layout = new QHBoxLayout;
layout->addWidget(new QLabel("Hello World!"));
setLayout(layout);
}
ConfigWidget::ConfigWidget(QWidget* parent)
: magnesia::ConfigWidget(parent) {
auto* layout = new QVBoxLayout;
auto* create_button = new QPushButton("Open Example");
connect(create_button, &QPushButton::clicked, this,
[] {
Application::instance().openActivity(new Example, "Example");
});
layout->addWidget(create_button);
setLayout(layout);
}
}
// register activity //
namespace magnesia::activities {
inline constexpr std::array all{
// --snip--
example::metadata,
// --snip--
};
}
Settings Activity
- Edit Settings
- Manage Certificates and Keys
SettingsManager
- Settings grouped in Domains
- Domains defined by (Activity) developer
Define new Settings
defineSettingDomain(
"general", { // domain name
QSharedPointer<magnesia::IntSetting> { // type of setting
new magnesia::IntSetting {
"opcua_poll_intervall", // internal name
"OPC UA Polling Interval", // human readable name
"in milliseconds", // description
500, 10, 30000}}, // default, min, max
QSharedPointer<magnesia::EnumSetting>{
new magnesia::EnumSetting{
"default_color", "Default Color", "The color to use everywhere.",
magnesia::EnumSettingValue{"green"},
{
magnesia::EnumSettingValue{"green"},
magnesia::EnumSettingValue{"blue"},
magnesia::EnumSettingValue{"red"},
}}}
});
Update Settings
Application::instance()
.getSettingsManager()
.setIntSetting({"opcua_poll_intervall", "general"}, 700);
Retrieve Settings
Application::instance()
.getSettingsManager()
.getIntSetting({"opcua_poll_intervall", "general"})
.value();
Reset Settings
Application::instance()
.getSettingsManager()
.resetSetting({"opcua_poll_intervall", "general"});
Setting Types
- Bool
- String
- Int
- Double
- Enum
- HistoricServerConnection
- Certificate
- KeySetting
- ApplicationCertificate
- Layout
StorageManager
- Declared in StorageManager
- Defined in SQLStorageManager
- Migrations
Store Data
StorageId cert_id = Application::instance()
.getStorageManager()
.storeCertificate(my_cert);
Retrieve Data
QSslCertificate cert = Application::instance()
.getStorageManager()
.getCertificate(cert_id).value();
Retrieve All
QList<std::pair<StorageId, QSslCertificate>> certs =
Application::instance().getStorageManager().getAllCertificates();
Notice Change
signals:
void certificateChanged(StorageId, StorageChange);
void keyChanged(StorageId, StorageChange);
void applicationCertificateChanged(StorageId, StorageChange);
void layoutChanged(StorageId, LayoutGroup, Domain, StorageChange);
void historicServerConnectionChanged(StorageId, StorageChange);
void kvChanged(QString, Domain, StorageChange);
enum class StorageChange {
Created,
Modified,
Deleted,
};
- Cascade Deletion
- e.g. Certificate → ApplicationCertificate → HistoricServerConnection → HistoricServerConnectionSetting
Certificate Activity
- Create/View ApplicationCertificates
Create
View
DataViewer
Panel Development
// example.hpp //
namespace magnesia::activities::dataviewer::panels::example {
class ExamplePanel : public Panel {
public:
explicit ExamplePanel(DataViewer*, QWidget* = nullptr);
[[nodiscard]] const PanelMetadata& metadata() const noexcept override;
};
inline constexpr PanelMetadata metadata{
.id = u"example",
.name = u"Example",
.create = create_helper<ExamplePanel>,
};
}
// example.cpp //
namespace magnesia::activities::dataviewer::panels::example {
ExamplePanel::ExamplePanel(DataViewer* dataviewer, QWidget* parent)
: Panel(dataviewer, Panels::example, parent) {
auto* layout = new QHBoxLayout;
layout->addWidget(new QLabel("Hello World!"));
setLayout(layout);
}
const PanelMetadata& ExamplePanel::metadata() const noexcept {
return example::metadata;
};
}
// register panel //
namespace magnesia::activities::dataviewer::panels {
inline constexpr std::array all{
// --snip--
example::metadata,
};
enum class Panels : unsigned {
// --snip--
example = 0x1 << 5,
};
}
TreeView
AttributeView
NodeView
ReferenceView
LogView
Router
- Open Activity without knowing it
URL Handler
namespace magnesia::activities::settings {
class SettingsUrlHandler: public URLHandler {
public:
explicit SettingsUrlHandler(Settings* activity);
bool handleURL(const QUrl& url) override;
private:
Settings* m_activity{nullptr};
};
}
Open URL
Application::instance().getRouter().
route("settings:focus-domain?domain=general");
Extensibility
- Easy to develop/add new
- Activities
- Panels
- Settings
- State of the art CMake build system
Build and Dependencies
- C++20
- CMake
- Dependencies in all major Linux Distros (including Debian)
- gcc 12.2.0 / clang 14.0.6 or newer
- cmake 3.25.0 or newer
- Qt 6.4.2 or newer
- open62541pp 0.13.0 (via CMake's FETCHCONTENT)
- Nix Flake
CI
- Implemented in Shell Scripts
- Runs locally
- Independent of GitLab
Code Docs
Process / Tooling
- Full meetings weekly
- Where are we?
- What needs to happen?
- Actual work alone / in pairs
So much Git!
Pflichtenheft Phase
- 24 pages
- LaTeX
- Graphics with draw.io
- Git
- 59 Merge-Requests (MRs)
- In German
Design Phase
- 33 pages
- LaTeX
- Graphics in TikZ, draw.io, Inkscape, qt-creator
- Git
- 51 MRs
- Human approval process
- In English
Implementation / QA Phase
- 11k lines of code (+5k blank and comments)
- Neovim, VSCodium, CLion
- Git
- 101 MRs
- Human approval process
- CI
- In English
Presentation
- 22 slides
- Reveal.js
- Git (directly on main)
- In English
Challenges
- Different Levels of Skill
- C++ new for 4/6
- Qt new for 5/6
- OPC UA new for 6/6
- Solution: Review Process
Did we make it?
- 33/34 must-have criteria from Pflichtenheft
- OPC UA doesn't allow subscribing Node references
- 3/13 nice-to-have criteria
- Implemented according to Design:
- Storage/Settings
- Activity System
- Layout System
- ...
- Redesigned in implementation phase:
- OPC UA abstraction
Lessons Learned
- Git, C++, Qt, OPC UA
- Communication
- Splitting work with different skill levels
- Lift as You Climb
Magnesia PSE
Magnesia PSE
Extensible OPC UA Client Working Title: Magnesia