commit a681c6da6b563cd0cf43ce04914267370615e107
Author: m.heisig <m.heisig@heisig-gmbh.de>
Date:   Sat Nov 8 13:56:28 2025 +0100

    Initial commit

diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..2157908
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1,219 @@
+# Byte-compiled / optimized / DLL files
+__pycache__/
+*.py[codz]
+*$py.class
+
+# C extensions
+*.so
+
+# Distribution / packaging
+.Python
+build/
+develop-eggs/
+dist/
+downloads/
+eggs/
+.eggs/
+lib/
+lib64/
+parts/
+sdist/
+var/
+wheels/
+share/python-wheels/
+*.egg-info/
+.installed.cfg
+*.egg
+MANIFEST
+
+# PyInstaller
+#   Usually these files are written by a python script from a template
+#   before PyInstaller builds the exe, so as to inject date/other infos into it.
+*.manifest
+*.spec
+
+# Installer logs
+pip-log.txt
+pip-delete-this-directory.txt
+
+# Unit test / coverage reports
+htmlcov/
+.tox/
+.nox/
+.coverage
+.coverage.*
+.cache
+nosetests.xml
+coverage.xml
+*.cover
+*.py.cover
+.hypothesis/
+.pytest_cache/
+cover/
+
+# Translations
+*.mo
+*.pot
+
+# Django stuff:
+*.log
+local_settings.py
+db.sqlite3
+db.sqlite3-journal
+
+# Flask stuff:
+instance/
+.webassets-cache
+
+# Scrapy stuff:
+.scrapy
+
+# Sphinx documentation
+docs/_build/
+
+# PyBuilder
+.pybuilder/
+target/
+
+# Jupyter Notebook
+.ipynb_checkpoints
+
+# IPython
+profile_default/
+ipython_config.py
+
+# pyenv
+#   For a library or package, you might want to ignore these files since the code is
+#   intended to run in multiple environments; otherwise, check them in:
+# .python-version
+
+# pipenv
+#   According to pypa/pipenv#598, it is recommended to include Pipfile.lock in version control.
+#   However, in case of collaboration, if having platform-specific dependencies or dependencies
+#   having no cross-platform support, pipenv may install dependencies that don't work, or not
+#   install all needed dependencies.
+# Pipfile.lock
+
+# UV
+#   Similar to Pipfile.lock, it is generally recommended to include uv.lock in version control.
+#   This is especially recommended for binary packages to ensure reproducibility, and is more
+#   commonly ignored for libraries.
+# uv.lock
+
+# poetry
+#   Similar to Pipfile.lock, it is generally recommended to include poetry.lock in version control.
+#   This is especially recommended for binary packages to ensure reproducibility, and is more
+#   commonly ignored for libraries.
+#   https://python-poetry.org/docs/basic-usage/#commit-your-poetrylock-file-to-version-control
+# poetry.lock
+# poetry.toml
+
+# pdm
+#   Similar to Pipfile.lock, it is generally recommended to include pdm.lock in version control.
+#   pdm recommends including project-wide configuration in pdm.toml, but excluding .pdm-python.
+#   https://pdm-project.org/en/latest/usage/project/#working-with-version-control
+# pdm.lock
+# pdm.toml
+.pdm-python
+.pdm-build/
+
+# pixi
+#   Similar to Pipfile.lock, it is generally recommended to include pixi.lock in version control.
+# pixi.lock
+#   Pixi creates a virtual environment in the .pixi directory, just like venv module creates one
+#   in the .venv directory. It is recommended not to include this directory in version control.
+.pixi
+
+# PEP 582; used by e.g. github.com/David-OConnor/pyflow and github.com/pdm-project/pdm
+__pypackages__/
+
+# Celery stuff
+celerybeat-schedule
+celerybeat.pid
+
+# Redis
+*.rdb
+*.aof
+*.pid
+
+# RabbitMQ
+mnesia/
+rabbitmq/
+rabbitmq-data/
+
+# ActiveMQ
+activemq-data/
+
+# SageMath parsed files
+*.sage.py
+
+# Environments
+.env
+.envrc
+.venv
+env/
+venv/
+ENV/
+env.bak/
+venv.bak/
+
+# Spyder project settings
+.spyderproject
+.spyproject
+
+# Rope project settings
+.ropeproject
+
+# mkdocs documentation
+/site
+
+# mypy
+.mypy_cache/
+.dmypy.json
+dmypy.json
+
+# Pyre type checker
+.pyre/
+
+# pytype static type analyzer
+.pytype/
+
+# Cython debug symbols
+cython_debug/
+
+# PyCharm
+#   JetBrains specific template is maintained in a separate JetBrains.gitignore that can
+#   be found at https://github.com/github/gitignore/blob/main/Global/JetBrains.gitignore
+#   and can be added to the global gitignore or merged into this file.  For a more nuclear
+#   option (not recommended) you can uncomment the following to ignore the entire idea folder.
+# .idea/
+
+# Abstra
+#   Abstra is an AI-powered process automation framework.
+#   Ignore directories containing user credentials, local state, and settings.
+#   Learn more at https://abstra.io/docs
+.abstra/
+
+# Visual Studio Code
+#   Visual Studio Code specific template is maintained in a separate VisualStudioCode.gitignore 
+#   that can be found at https://github.com/github/gitignore/blob/main/Global/VisualStudioCode.gitignore
+#   and can be added to the global gitignore or merged into this file. However, if you prefer, 
+#   you could uncomment the following to ignore the entire vscode folder
+.vscode/
+
+# Ruff stuff:
+.ruff_cache/
+
+# PyPI configuration file
+.pypirc
+
+# Marimo
+marimo/_static/
+marimo/_lsp/
+__marimo__/
+
+# Streamlit
+.streamlit/secrets.toml
+
+static/*
+certificates/*
\ No newline at end of file
diff --git a/globalConfigs.py b/globalConfigs.py
new file mode 100644
index 0000000..f098d7f
--- /dev/null
+++ b/globalConfigs.py
@@ -0,0 +1,28 @@
+from pathlib import Path
+import socket
+
+# Certificate settings
+CERT_BASE = Path(__file__).parent
+CERT = Path(CERT_BASE / f"certificates/peer-certificate.der")
+PRIVATE_KEY = Path(CERT_BASE / f"certificates/peer-private-key.pem")
+HOST_NAME = socket.gethostname()
+CLIENT_APP_URI = f"urn:{HOST_NAME}:client:hmi"
+
+# OPC UA settings
+OPC_UA_URL = "opc.tcp://192.168.42.1:4840"
+OPC_UA_USER = "hmi"
+OPC_UA_PW = "hmi"
+#OPC_UA_URL = "opc.tcp://192.168.56.101:4840"
+#OPC_UA_USER = "twincat"
+#OPC_UA_PW = "twincat"
+NAMESPACE = "urn:BeckhoffAutomation:Ua:PLC1"
+NS_IDX = 0
+
+CHECK_INTERVAL = 1.0  # seconds
+RECONNECT_INTERVAL = 5.0 # seconds
+
+# Publishing interval to the clients (rate limiting)
+PUBLISH_INTERVAL = 0.1 # 200 ms
+
+# Path to the nodes list
+NODE_IDS_FILE_PATH = Path(CERT_BASE / f"nodeList.txt")
\ No newline at end of file
diff --git a/globalData.py b/globalData.py
new file mode 100644
index 0000000..a9f686e
--- /dev/null
+++ b/globalData.py
@@ -0,0 +1,12 @@
+import asyncio
+from asyncua import Client
+from asyncua.common.subscription import Subscription
+
+opc_ua_client: Client
+clients = {} # {WebSocket: set(subscribed_tags)}
+node_storage = {}
+event_storage = {}
+queue = asyncio.Queue(maxsize=10000)
+event_queue = asyncio.Queue(maxsize=1000)
+subscription_handler: Subscription
+subscribed_nodes = set()
\ No newline at end of file
diff --git a/main.py b/main.py
new file mode 100644
index 0000000..5943979
--- /dev/null
+++ b/main.py
@@ -0,0 +1,115 @@
+from fastapi import FastAPI #, HTTPException
+from routers import websocket
+from fastapi.middleware.cors import CORSMiddleware
+#from starlette import status
+#from fastapi.staticfiles import StaticFiles
+#from models import SemiAutoControl, SemiAutoBatteryStatus
+
+import asyncio
+import msgpack
+
+#from globalData import node_storage, clients
+import globalData as gd
+import globalConfigs as gc
+from opcuaHandler import initOPCUAConnection, connection_watcher
+
+update_buffer = {}
+
+async def data_consumer(queue):
+    """Asynchronous consumer that stores the latest values."""
+    while True:
+        nodeid, val = await queue.get()
+        gd.node_storage[nodeid] = val
+        update_buffer[nodeid] = val
+        queue.task_done()
+
+async def event_consumer(queue):
+    while True:
+        node_id, event_data = await queue.get()
+        print("Got new event", event_data)
+        if node_id in gd.event_storage:
+            event_data.Message = gd.event_storage[node_id].Message
+            gd.event_storage[node_id].update(event_data)
+        else:
+            gd.event_storage[node_id] = event_data
+
+        print(gd.event_storage)
+        
+        for ws in list(gd.clients):
+            print("Sending event:", {"e": {node_id: event_data}})
+            await ws.send_bytes(msgpack.packb({"e": {node_id: event_data}}))
+        queue.task_done()
+
+async def broadcast_deltas(changes: dict):
+    payload = msgpack.packb({"u": changes})
+    for ws, subscribed_tags in list(gd.clients.items()):
+        relevant = {tag: val for tag, val in changes.items() if tag in subscribed_tags}
+        if relevant:
+            await ws.send_bytes(msgpack.packb({"u": relevant}))
+
+async def broadcast_loop():
+    global update_buffer
+    while True:
+        await asyncio.sleep(gc.PUBLISH_INTERVAL)
+
+        if not update_buffer:
+            continue
+
+        changes = dict(update_buffer)
+        update_buffer.clear()
+
+        for ws, subscribed_tags in list(gd.clients.items()):
+            relevant = {tag: val for tag, val in changes.items() if tag in subscribed_tags}
+            if relevant:
+                await ws.send_bytes(msgpack.packb({"u": relevant}))
+
+
+async def lifespan(app: FastAPI):
+    """
+    FastAPI lifespan context — creates the client and starts the watcher.loading="warning"
+    """
+    await initOPCUAConnection()
+
+    # Launch the background watcher task for the opc ua connection
+    watcher_task = asyncio.create_task(connection_watcher())
+
+    # Lunch data consumer task for node value changed events
+    consumer_task = asyncio.create_task(data_consumer(gd.queue))
+    event_consumer_task = asyncio.create_task(event_consumer(gd.event_queue))
+    broadcast_task = asyncio.create_task(broadcast_loop())
+    
+
+    yield  # Application runs while this yields
+
+    # Cleanup on shutdown
+    watcher_task.cancel()
+    broadcast_task.cancel()
+    consumer_task.cancel()
+    event_consumer_task.cancel()
+    try:
+        await watcher_task
+        await consumer_task
+        await broadcast_task
+        await event_consumer_task
+    except asyncio.CancelledError:
+        pass
+
+
+app = FastAPI(lifespan=lifespan)
+origins = [
+        "http://localhost:3000",
+        "http://127.0.0.1:3000",
+        # Fügen Sie hier weitere erforderlich Ursprünge hinzu
+    ]
+app.add_middleware(
+        CORSMiddleware,
+        allow_origins=origins,
+        allow_credentials=True,
+        allow_methods=["*"], # Erlaubt alle HTTP-Methoden (GET, POST, etc.)
+        allow_headers=["*"], # Erlaubt alle Header
+    )
+app.include_router(websocket.router)
+#app.include_router(semiAuto.router)
+
+# Serve the built frontend
+#app.mount("/assets", StaticFiles(directory="static/assets"), name="assets")
diff --git a/models.py b/models.py
new file mode 100644
index 0000000..508f755
--- /dev/null
+++ b/models.py
@@ -0,0 +1,14 @@
+from pydantic import BaseModel
+from asyncua import ua
+from typing import Any
+
+class SemiAutoControl(BaseModel):
+    string: int
+    module: int
+    unit: int
+    enable: bool
+
+class WriteNodeCommand(BaseModel):
+    nodeId: str
+    nodeValue: Any
+    nodeType: ua.VariantType
diff --git a/nodeList.txt b/nodeList.txt
new file mode 100644
index 0000000..50e4798
--- /dev/null
+++ b/nodeList.txt
@@ -0,0 +1,235 @@
+# Semi auto mode control string 1
+ns=4;s=GVL_SCADA.stSemiAutoBatteryEnable[0].stSemiAutoModul1.xSemiAutoEnableUnit1
+ns=4;s=GVL_SCADA.stSemiAutoBatteryEnable[0].stSemiAutoModul1.xSemiAutoEnableUnit2
+ns=4;s=GVL_SCADA.stSemiAutoBatteryEnable[0].stSemiAutoModul1.xSemiAutoEnableUnit3
+ns=4;s=GVL_SCADA.stSemiAutoBatteryEnable[0].stSemiAutoModul1.xSemiAutoEnableUnit4
+ns=4;s=GVL_SCADA.stSemiAutoBatteryEnable[0].stSemiAutoModul2.xSemiAutoEnableUnit1
+ns=4;s=GVL_SCADA.stSemiAutoBatteryEnable[0].stSemiAutoModul2.xSemiAutoEnableUnit2
+ns=4;s=GVL_SCADA.stSemiAutoBatteryEnable[0].stSemiAutoModul2.xSemiAutoEnableUnit3
+ns=4;s=GVL_SCADA.stSemiAutoBatteryEnable[0].stSemiAutoModul2.xSemiAutoEnableUnit4
+ns=4;s=GVL_SCADA.stSemiAutoBatteryEnable[0].stSemiAutoModul3.xSemiAutoEnableUnit1
+ns=4;s=GVL_SCADA.stSemiAutoBatteryEnable[0].stSemiAutoModul3.xSemiAutoEnableUnit2
+ns=4;s=GVL_SCADA.stSemiAutoBatteryEnable[0].stSemiAutoModul3.xSemiAutoEnableUnit3
+ns=4;s=GVL_SCADA.stSemiAutoBatteryEnable[0].stSemiAutoModul3.xSemiAutoEnableUnit4
+
+# Semi auto mode control string 2
+ns=4;s=GVL_SCADA.stSemiAutoBatteryEnable[1].stSemiAutoModul1.xSemiAutoEnableUnit1
+ns=4;s=GVL_SCADA.stSemiAutoBatteryEnable[1].stSemiAutoModul1.xSemiAutoEnableUnit2
+ns=4;s=GVL_SCADA.stSemiAutoBatteryEnable[1].stSemiAutoModul1.xSemiAutoEnableUnit3
+ns=4;s=GVL_SCADA.stSemiAutoBatteryEnable[1].stSemiAutoModul1.xSemiAutoEnableUnit4
+ns=4;s=GVL_SCADA.stSemiAutoBatteryEnable[1].stSemiAutoModul2.xSemiAutoEnableUnit1
+ns=4;s=GVL_SCADA.stSemiAutoBatteryEnable[1].stSemiAutoModul2.xSemiAutoEnableUnit2
+ns=4;s=GVL_SCADA.stSemiAutoBatteryEnable[1].stSemiAutoModul2.xSemiAutoEnableUnit3
+ns=4;s=GVL_SCADA.stSemiAutoBatteryEnable[1].stSemiAutoModul2.xSemiAutoEnableUnit4
+ns=4;s=GVL_SCADA.stSemiAutoBatteryEnable[1].stSemiAutoModul3.xSemiAutoEnableUnit1
+ns=4;s=GVL_SCADA.stSemiAutoBatteryEnable[1].stSemiAutoModul3.xSemiAutoEnableUnit2
+ns=4;s=GVL_SCADA.stSemiAutoBatteryEnable[1].stSemiAutoModul3.xSemiAutoEnableUnit3
+ns=4;s=GVL_SCADA.stSemiAutoBatteryEnable[1].stSemiAutoModul3.xSemiAutoEnableUnit4
+
+# Auto control mode
+ns=4;s=GVL_SCADA.eCurrentControlMode
+ns=4;s=GVL_SCADA.xCanChangeControlMode
+
+# String 2 - Modul 2 - Unit 1
+# Spannungsmessung
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit1.stE31.rValue
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit1.stE31.sUnit
+
+# Druck segment
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit1.stP11.rValue
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit1.stP11.sUnit
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit1.stP21.rValue
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit1.stP21.sUnit
+
+# Druck tank
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit1.stP12.rValue
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit1.stP12.sUnit
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit1.stP22.rValue
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit1.stP22.sUnit
+
+# Temperatur
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit1.stT11.rValue
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit1.stT11.sUnit
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit1.stT21.rValue
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit1.stT21.sUnit
+
+# Ventile
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit1.stNS12.stOpenButton.eFeedback
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit1.stNS12.stOpenButton.xRelease
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit1.stNS12.stCloseButton.eFeedback
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit1.stNS12.stCloseButton.xRelease
+
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit1.stNS22.stOpenButton.eFeedback
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit1.stNS22.stOpenButton.xRelease
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit1.stNS22.stCloseButton.eFeedback
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit1.stNS22.stCloseButton.xRelease
+
+# Pumpen
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit1.stNS11.stSetpoint.rValue
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit1.stNS11.stProcessValue.rValue
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit1.stNS11.stProcessValue.sUnit
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit1.stNS11.stStartButton.eFeedback
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit1.stNS11.stStartButton.xRelease
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit1.stNS11.stStopButton.eFeedback
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit1.stNS11.stStopButton.xRelease
+
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit1.stNS21.stSetpoint.rValue
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit1.stNS21.stProcessValue.rValue
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit1.stNS21.stProcessValue.sUnit
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit1.stNS21.stStartButton.eFeedback
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit1.stNS21.stStartButton.xRelease
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit1.stNS21.stStopButton.eFeedback
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit1.stNS21.stStopButton.xRelease
+
+# String 2 - Modul 2 - Unit 2
+# Spannungsmessung
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit2.stE31.rValue
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit2.stE31.sUnit
+
+# Druck segment
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit2.stP11.rValue
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit2.stP11.sUnit
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit2.stP21.rValue
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit2.stP21.sUnit
+
+# Druck tank
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit2.stP12.rValue
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit2.stP12.sUnit
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit2.stP22.rValue
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit2.stP22.sUnit
+
+# Temperatur
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit2.stT11.rValue
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit2.stT11.sUnit
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit2.stT21.rValue
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit2.stT21.sUnit
+
+# Ventile
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit2.stNS12.stOpenButton.eFeedback
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit2.stNS12.stOpenButton.xRelease
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit2.stNS12.stCloseButton.eFeedback
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit2.stNS12.stCloseButton.xRelease
+
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit2.stNS22.stOpenButton.eFeedback
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit2.stNS22.stOpenButton.xRelease
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit2.stNS22.stCloseButton.eFeedback
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit2.stNS22.stCloseButton.xRelease
+
+# Pumpen
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit2.stNS11.stSetpoint.rValue
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit2.stNS11.stProcessValue.rValue
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit2.stNS11.stProcessValue.sUnit
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit2.stNS11.stStartButton.eFeedback
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit2.stNS11.stStartButton.xRelease
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit2.stNS11.stStopButton.eFeedback
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit2.stNS11.stStopButton.xRelease
+
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit2.stNS21.stSetpoint.rValue
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit2.stNS21.stProcessValue.rValue
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit2.stNS21.stProcessValue.sUnit
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit2.stNS21.stStartButton.eFeedback
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit2.stNS21.stStartButton.xRelease
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit2.stNS21.stStopButton.eFeedback
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit2.stNS21.stStopButton.xRelease
+
+# String 2 - Modul 2 - Unit 3
+# Spannungsmessung
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit3.stE31.rValue
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit3.stE31.sUnit
+
+# Druck segment
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit3.stP11.rValue
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit3.stP11.sUnit
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit3.stP21.rValue
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit3.stP21.sUnit
+
+# Druck tank
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit3.stP12.rValue
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit3.stP12.sUnit
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit3.stP22.rValue
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit3.stP22.sUnit
+
+# Temperatur
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit3.stT11.rValue
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit3.stT11.sUnit
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit3.stT21.rValue
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit3.stT21.sUnit
+
+# Ventile
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit3.stNS12.stOpenButton.eFeedback
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit3.stNS12.stOpenButton.xRelease
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit3.stNS12.stCloseButton.eFeedback
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit3.stNS12.stCloseButton.xRelease
+
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit3.stNS22.stOpenButton.eFeedback
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit3.stNS22.stOpenButton.xRelease
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit3.stNS22.stCloseButton.eFeedback
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit3.stNS22.stCloseButton.xRelease
+
+# Pumpen
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit3.stNS11.stSetpoint.rValue
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit3.stNS11.stProcessValue.rValue
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit3.stNS11.stProcessValue.sUnit
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit3.stNS11.stStartButton.eFeedback
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit3.stNS11.stStartButton.xRelease
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit3.stNS11.stStopButton.eFeedback
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit3.stNS11.stStopButton.xRelease
+
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit3.stNS21.stSetpoint.rValue
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit3.stNS21.stProcessValue.rValue
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit3.stNS21.stProcessValue.sUnit
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit3.stNS21.stStartButton.eFeedback
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit3.stNS21.stStartButton.xRelease
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit3.stNS21.stStopButton.eFeedback
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit3.stNS21.stStopButton.xRelease
+
+# String 2 - Modul 2 - Unit 4
+# Spannungsmessung
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit4.stE31.rValue
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit4.stE31.sUnit
+
+# Druck segment
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit4.stP11.rValue
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit4.stP11.sUnit
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit4.stP21.rValue
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit4.stP21.sUnit
+
+# Druck tank
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit4.stP12.rValue
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit4.stP12.sUnit
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit4.stP22.rValue
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit4.stP22.sUnit
+
+# Temperatur
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit4.stT11.rValue
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit4.stT11.sUnit
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit4.stT21.rValue
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit4.stT21.sUnit
+
+# Ventile
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit4.stNS12.stOpenButton.eFeedback
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit4.stNS12.stOpenButton.xRelease
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit4.stNS12.stCloseButton.eFeedback
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit4.stNS12.stCloseButton.xRelease
+
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit4.stNS22.stOpenButton.eFeedback
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit4.stNS22.stOpenButton.xRelease
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit4.stNS22.stCloseButton.eFeedback
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit4.stNS22.stCloseButton.xRelease
+
+# Pumpen
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit4.stNS11.stSetpoint.rValue
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit4.stNS11.stProcessValue.rValue
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit4.stNS11.stProcessValue.sUnit
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit4.stNS11.stStartButton.eFeedback
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit4.stNS11.stStartButton.xRelease
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit4.stNS11.stStopButton.eFeedback
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit4.stNS11.stStopButton.xRelease
+
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit4.stNS21.stSetpoint.rValue
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit4.stNS21.stProcessValue.rValue
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit4.stNS21.stProcessValue.sUnit
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit4.stNS21.stStartButton.eFeedback
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit4.stNS21.stStartButton.xRelease
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit4.stNS21.stStopButton.eFeedback
+ns=4;s=GVL_SCADA.stHMIInterface[1].stHMIInterfaceModule2.stHMIInterfaceUnit4.stNS21.stStopButton.xRelease
\ No newline at end of file
diff --git a/oldCode.py b/oldCode.py
new file mode 100644
index 0000000..0f4ae6d
--- /dev/null
+++ b/oldCode.py
@@ -0,0 +1,45 @@
+#from fastapi.responses import StreamingResponse, FileResponse
+
+# @app.get("/events")
+# async def sse_endpoint():
+#     """SSE endpoint to stream OPC UA updates"""
+#     return StreamingResponse(event_stream(), media_type="text/event-stream")
+
+# Serve index.html
+#@app.get("/")
+#async def serve_frontend():
+#    return FileResponse("static/index.html")
+
+# @app.get("/modes/semiAuto/{strng}")
+# async def semiAutoStringEventStream(strng):
+#     return StreamingResponse(strng_semi_auto_data_stream(), media_type="text/event-stream")
+
+# async def event_stream():
+#     # Send current value immediately if available
+#     if latest_value["value"] is not None:
+#         yield f"data: {json.dumps(latest_value)}\n\n"
+
+#     while True:
+#         await new_value_event.wait()  # wait for new value
+#         data = json.dumps(latest_value)
+#         yield f"data: {data}\n\n"
+#         new_value_event.clear()  # reset event and wait for next update
+
+# async def strng_semi_auto_data_stream():
+#     while True:
+#         await new_value_event.wait()
+#         data
+
+# @app.get("/getMode")
+# async def set_mode(request: Request):
+#     client = request.app.state.opcua_client
+#     nsidx = request.app.state.ns_idx
+#     #node = client.get_node(f"ns={nsidx};s=GVL_SCADA.eRequestedControlMode")
+#     #node = client.get_node(f"ns={nsidx};s=GVL_SCADA.eCurrentControlMode")
+#     try:
+#         node = client.get_node(f"ns={nsidx};s=GVL_SCADA.stHMIInterface[0].stHMIInterfaceModule3.stHMIInterfaceUnit1.stP11.rValue")
+#         value = await node.read_value()
+#         print(value)
+#         return {"node_id": "GVL_SCADA.eCurrentControlMode", "value": value}
+#     except:
+#         return {"node_id": "GVL_SCADA.eCurrentControlMode", "value": 0.0}
\ No newline at end of file
diff --git a/opcuaHandler.py b/opcuaHandler.py
new file mode 100644
index 0000000..2fb3765
--- /dev/null
+++ b/opcuaHandler.py
@@ -0,0 +1,191 @@
+import os
+
+from asyncua import Client, ua, Node
+from asyncua.crypto.security_policies import SecurityPolicyBasic256Sha256
+from asyncua.crypto.cert_gen import setup_self_signed_certificate
+from cryptography.x509.oid import ExtendedKeyUsageOID
+
+import asyncio
+
+import globalConfigs as gc
+import globalData as gd
+
+
+new_value_event = asyncio.Event()  # signals when a new value arrives
+
+class SubHandler:
+    """
+    Subscription Handler. To receive events from server for a subscription
+    This class is just a sample class. Whatever class having these methods can be used
+    """
+
+    def __init__(self, queue, event_queue):
+        self.queue = queue
+        self.event_queue = event_queue
+
+    def datachange_notification(self, node: Node, val, data):
+        """
+        called for every datachange notification from server
+        """
+        self.queue.put_nowait((node.nodeid.to_string(), val))
+
+    def event_notification(self, event: ua.EventNotificationList):
+        """
+        called for every event notification from server
+        """
+        # print("=== Event empfangen ===")
+        # print("NodeId:", event.NodeId.Identifier)
+        # print("Severity:", event.Severity)
+        # print("Message:", event.Message.Text)
+        # print("ActiveState:", getattr(event, "ActiveState/Id"))
+        # print("ActiveStateTransTime:", getattr(event, "ActiveState/TransitionTime"))
+        # print("ConfirmedState:", getattr(event, "ConfirmedState/Id"))
+        # print("ConfirmedStateTransTime:", getattr(event, "ConfirmedState/TransitionTime"))
+        # print("Retain:", event.Retain)
+        # print("------------------------")
+
+        event_data = {
+            "Severity": event.Severity,
+            "Message": event.Message.Text,
+            "ActiveState": getattr(event, "ActiveState/Id"),
+            "ConfirmedState": getattr(event, "ConfirmedState/Id"),
+            "ActiveStateTransTime": getattr(event, "ActiveState/TransitionTime").isoformat(),
+            "ConfirmedStateTransTime": getattr(event, "ConfirmedState/TransitionTime").isoformat(),
+            "Retain": event.Retain
+        }
+        print("Got event")
+        self.event_queue.put_nowait((event.NodeId.Identifier, event_data))
+
+        
+
+    def status_change_notification(self, status: ua.StatusChangeNotification):
+        """
+        called for every status change notification from server
+        """
+        print("status_notification %s", status)
+
+# def load_node_ids():
+#     if not gc.NODE_IDS_FILE_PATH.exists():
+#         return []
+    
+#     with open(gc.NODE_IDS_FILE_PATH, "r", encoding="utf-8") as f:
+#             node_ids = [line.strip() for line in f if line.strip() and not line.startswith("#")]
+
+#     if not node_ids:
+#         raise ValueError(f"No node IDs found in {gc.NODE_IDS_FILE_PATH}")
+#     return node_ids
+
+# async def createSubscriptions():
+
+#     subscription = await gd.opc_ua_client.create_subscription(250, SubHandler(gd.queue))
+#     node_ids = load_node_ids()
+#     nodes = [gd.opc_ua_client.get_node(f"{nid}") for nid in node_ids]
+#     await subscription.subscribe_data_change(nodes)
+
+async def connection_watcher2():
+    await initOPCUAConnection()
+
+    connected = False
+
+    while not connected:
+        try:
+            # In the first round we can use the normal connect
+            await gd.opc_ua_client.connect()
+            connected = True
+        except Exception:
+            print(f"Reconnecting in {gc.RECONNECT_INTERVAL} seconds")
+            await asyncio.sleep(gc.RECONNECT_INTERVAL)
+        
+
+    # Create subscriptions
+    gd.subscription_handler = await gd.opc_ua_client.create_subscription(250, SubHandler(gd.queue, gd.event_queue))
+
+    # Create an event subscription
+    event_logger_node = gd.opc_ua_client.get_node("ns=8;s=eventlogger")
+    await gd.subscription_handler.subscribe_events(event_logger_node, evtypes=[ua.ObjectIds.BaseEventType, "ns=5;i=4000"])
+
+    # Periodically check for connection
+    state = 0
+    while True:
+        match (state):
+            case 0:
+                try:
+                    await gd.opc_ua_client.connect_sessionless()
+                    await gd.opc_ua_client.create_session()
+                except Exception:
+
+
+        await asyncio.sleep(gc.CHECK_INTERVAL)
+        try:
+            await gd.opc_ua_client.check_connection()
+        except ua.uaerrors._auto.BadConnectionClosed:
+            connected = False
+            print(f"Reconnecting in {gc.RECONNECT_INTERVAL} seconds")
+            await asyncio.sleep(gc.RECONNECT_INTERVAL)
+        
+
+
+async def connection_watcher():
+    """
+    Background task to keep checking OPC UA client connection.
+    Reconnects automatically if disconnected.
+    """
+    while True:
+        try:
+            gd.opc_ua_client = Client(url=gc.OPC_UA_URL)
+    
+            gd.opc_ua_client.application_uri = gc.CLIENT_APP_URI
+            await gd.opc_ua_client.set_security(
+                SecurityPolicyBasic256Sha256,
+                certificate=str(gc.CERT),
+                private_key=str(gc.PRIVATE_KEY)
+            )
+            gd.opc_ua_client.set_user(gc.OPC_UA_USER)
+            gd.opc_ua_client.set_password(gc.OPC_UA_PW)
+
+            async with gd.opc_ua_client:
+                print("Connected")
+                #print("Creating subscriptions")
+                #await createSubscriptions()
+                gd.subscription_handler = await gd.opc_ua_client.create_subscription(250, SubHandler(gd.queue, gd.event_queue))
+                event_logger_node = gd.opc_ua_client.get_node("ns=8;s=eventlogger")
+                await gd.subscription_handler.subscribe_events(event_logger_node, evtypes=[ua.ObjectIds.BaseEventType, "ns=5;i=4000"])
+                print("Registered events")
+                while True:
+                    await asyncio.sleep(gc.CHECK_INTERVAL)
+                    await gd.opc_ua_client.check_connection()  # Throws a exception if connection is lost
+        except ua.uaerrors._auto.BadConnectionClosed:
+            print("Lost connection")
+            print(f"Reconnecting in {gc.RECONNECT_INTERVAL} seconds")
+            await asyncio.sleep(gc.RECONNECT_INTERVAL)
+        except Exception as e:
+            print(e)
+            break
+            
+
+async def initOPCUAConnection():
+    if (not os.path.isfile(gc.CERT)) or (not os.path.isfile(gc.PRIVATE_KEY)):
+        await setup_self_signed_certificate(
+            gc.PRIVATE_KEY,
+            gc.CERT,
+            gc.CLIENT_APP_URI,
+            gc.HOST_NAME,
+            [ExtendedKeyUsageOID.CLIENT_AUTH],
+            {
+                "countryName": "DE",
+                "stateOrProvinceName": "NRW",
+                "localityName": "HMI backend",
+                "organizationName": "Heisig GmbH",
+            },
+        )
+
+    gd.opc_ua_client = Client(url=gc.OPC_UA_URL)
+    
+    gd.opc_ua_client.application_uri = gc.CLIENT_APP_URI
+    await gd.opc_ua_client.set_security(
+        SecurityPolicyBasic256Sha256,
+        certificate=str(gc.CERT),
+        private_key=str(gc.PRIVATE_KEY)
+    )
+    gd.opc_ua_client.set_user(gc.OPC_UA_USER)
+    gd.opc_ua_client.set_password(gc.OPC_UA_PW)
\ No newline at end of file
diff --git a/requirements.txt b/requirements.txt
new file mode 100644
index 0000000..e69de29
diff --git a/routers/__init__.py b/routers/__init__.py
new file mode 100644
index 0000000..e69de29
diff --git a/routers/websocket.py b/routers/websocket.py
new file mode 100644
index 0000000..4807e83
--- /dev/null
+++ b/routers/websocket.py
@@ -0,0 +1,62 @@
+from fastapi import WebSocket, APIRouter
+import msgpack
+import globalData as gd
+
+from asyncua import ua
+from models import WriteNodeCommand
+
+router = APIRouter()
+
+@router.websocket("/ws")
+async def websocket_endpoint(ws: WebSocket):
+    global clients
+    await ws.accept()
+    gd.clients[ws] = set()
+
+    try:
+        while True:
+            # empfange binäre Daten vom Client
+            raw = await ws.receive_bytes()
+            data = msgpack.unpackb(raw, raw=False)
+
+            # Subscription handling
+            if "subscribe" in data:
+                gd.clients[ws].update(data["subscribe"])
+                diff_set = gd.subscribed_nodes.symmetric_difference(data["subscribe"])
+                nodes = [gd.opc_ua_client.get_node(f"{nid}") for nid in diff_set]
+
+                #await gd.subscription_handler.subscribe_data_change(nodes)
+
+                initial_values = {
+                    nid: val
+                    for nid in gd.node_storage
+                    if (val := gd.node_storage.get(nid)) is not None
+                }
+
+                initial_events = {
+                    nid: val
+                    for nid in gd.event_storage
+                    if (val := gd.event_storage.get(nid)) is not None
+                }
+
+                #if initial_values:
+                await ws.send_bytes(msgpack.packb({"initial": {"values": initial_values, "events": initial_events}}))
+
+            elif "unsubscribe" in data:
+                gd.clients[ws].pop(data["unsubscribe"])
+
+            elif "command" in data:
+                await handle_command(data["command"])
+    except Exception:
+        if ws in gd.clients:
+            del gd.clients[ws]
+
+async def handle_command(cmd):
+    #print(f"Received command: {cmd}")
+    try:
+        wnc = WriteNodeCommand.model_validate(cmd)
+        node = gd.opc_ua_client.get_node(cmd["nodeId"])
+        dv = ua.DataValue(ua.Variant(wnc.nodeValue, wnc.nodeType))
+        await node.write_value(dv)
+    except Exception as e:
+        print(e)
\ No newline at end of file