Websocket Server for WinCC OA

Connect programs (e.g. Python Program) to WinCC OA through a Websocket Manager. Communication is JSON based, it’s simple to use with Python, see the Jupyter Notebook example Jupyter Notebook and the examples below. dpGet, dpSet, dpConnect, dpQueryConnect, dpGetPeriod, ... more functions may come...

Server Setup

oa4j is needed: https://rocworks.at/oa4j
Copy WCCOAjava.exe to <project>\bin directory
Copy WCCOAjava.dll to <project>\bin directory
Install java runtime: https://java.com/de/download/
Add C:\Program Files\Java\jre1.8.0_161\bin\server to PATH environment variable

Build Websocket Server

You need Maven and Java.

make.bat

copy wss\wss.jar to <project>\bin directory
copy wss\keystore.jks to <project>
copy lib directory to your <project>\lib directory
Add the following lines to your config file. Copy the paths ffrom the classpath.txt file. This file is created during the build.

[java]
classPath = "bin;bin/wss-1.0-SNAPSHOT.jar;lib/winccoa-java-1.0-SNAPSHOT.jar;lib/graphql-java-12.0.jar;lib/antlr4-runtime-4.7.2.jar;lib/slf4j-api-1.7.25.jar;lib/java-dataloader-2.1.1.jar;lib/reactive-streams-1.0.2.jar;lib/gson-2.8.2.jar;lib/websocket-server-9.4.8.v20171121.jar;lib/websocket-common-9.4.8.v20171121.jar;lib/websocket-api-9.4.8.v20171121.jar;lib/jetty-util-9.4.8.v20171121.jar;lib/jetty-io-9.4.8.v20171121.jar;lib/websocket-client-9.4.8.v20171121.jar;lib/jetty-client-9.4.8.v20171121.jar;lib/jetty-xml-9.4.8.v20171121.jar;lib/websocket-servlet-9.4.8.v20171121.jar;lib/javax.servlet-api-3.1.0.jar;lib/jetty-servlet-9.4.8.v20171121.jar;lib/jetty-security-9.4.8.v20171121.jar;lib/jetty-server-9.4.8.v20171121.jar;lib/jetty-http-9.4.8.v20171121.jar;lib/rxjava-1.3.5.jar"

Add a WCCOAjava manager to your project: -num 1 -cp bin/wss.jar -c wss/Server

Python Examples

see pyhton-client-example.py & python-client-plot.py!

Open Connection

import json
import ssl
from websocket import create_connection
url='wss://rocworks.no-ip.org:80/winccoa?username=demo&password=demo'
ws = create_connection(url, sslopt={"cert_reqs": ssl.CERT_NONE})

dpGetPeriod

cmd={'DpGetPeriod': {
 'Id': 1,
 'Dps':['ExampleDP_Trend1.'],
 'T1': '2018-02-07T18:10:00.000', 
 'T2': '2018-02-07T23:59:59.999',
 'Count': 0, # Optional (Default=0)
 'Ts': 0 # Optional (0...no ts in result, 1...ts as ms since epoch, 2...ts as ISO8601, 3/4...ts/values in separate arrays (ms/iso))
 }}
ws.send(json.dumps(cmd))
res=json.loads(ws.recv())
#print(res)
if "System1:ExampleDP_Trend1.:_offline.._value" in res["DpGetPeriodResult"]["Values"]:
 values=res["DpGetPeriodResult"]["Values"]["System1:ExampleDP_Trend1.:_offline.._value"]
 print(values)
else:
 print("no data found")
 
{
    "DpGetPeriodResult": {
        "Error": 0,
        "Id": 1,
        "Values": {
            "System1:ExampleDP_Trend1.:_offline.._value": [
                6.0,
                6.0,
                6.0
            ]
        }
    }
}

Plot result of dpGetPeriod

%matplotlib inline 
import matplotlib.pyplot as plt
plt.plot(values)
plt.ylabel('ExampleDP_Trend1.')
plt.show()

dpGet

cmd={'DpGet': {'Id': 2, 'Dps':['ExampleDP_Trend1.', 'ExampleDP_Trend2.']}}
ws.send(json.dumps(cmd))
res=json.loads(ws.recv())
print(json.dumps(res, indent=4, sort_keys=True))
{
    "DpGetResult": {
        "Error": 0,
        "Id": 2,
        "Values": {
            "System1:ExampleDP_Trend1.:_original.._value": 6.0,
            "System1:ExampleDP_Trend2.:_original.._value": 6.0
        }
    }
}

dpSet

from random import randint
cmd={'DpSet': {'Id': 3, 'Wait': True, 
 'Values':[{'Dp':'ExampleDP_Trend1.','Value': randint(0, 9)}, 
 {'Dp':'ExampleDP_Trend2.','Value': randint(0, 9)}]}}
ws.send(json.dumps(cmd))
res=json.loads(ws.recv())
print(json.dumps(res, indent=4, sort_keys=True))
{
    "Response": {
        "Code": 0,
        "Id": 3,
        "Message": ""
    }
}

dpConnect

from threading import Thread

def read():
    while True:
        res=json.loads(ws.recv())
        print(res)
Thread(target=read).start()
    
cmd={"DpConnect": {"Id": 4, "Dps": ["ExampleDP_Trend1."]}}
ws.send(json.dumps(cmd))

{
    "DpConnectResult": {
        "Error": 0,
        "Id": 4,
        "Values": {
            "System1:ExampleDP_Trend1.:_online.._value": 6.0
        }
    }
}

dpQueryConnect

cmd={'DpQueryConnect': {'Id': 5, 'Query':"SELECT '_online.._value' FROM 'ExampleDP_*.'", 'Answer': True}}
ws.send(json.dumps(cmd))
'''
{
    "DpQueryConnectResult": {
        "Error": 0,
        "Id": 5,
        "Header": [
            "",
            ":_online.._value"
        ],
        "Values": [
            [
                "System1:ExampleDP_Trend1.",
                6.0
            ]
        ]
    }
}
'''

vogler75/oa4j-wss