Enable WebSocket in OPC DA/AE/HDA Server with JSON return, FIRST TIME ever!
DCOM was developed more than 2 decades ago, which was the pillar of classic OPC. Nowadays people embrace for dynamical languages (JavaScript/Python etc) due to their simplicity and refuse to be trapped in DCOM configuration hell. Luckily with the popular adoption of WebSocket by most modern programming languages, it is possible to glue dynamical languages and legacy DCOM together.
This first time ever and ultimate solution, WebSocket4OPC, brings unparalleled experience to your desktop and mobile device. It utilizes WebSocket as network transportation layer with its full duplex feature. Comparing with DCOM's RPC protocol, WebSocket is much easy to use and more efficient. With the built-in WebSocket feature in Microsoft IIS, OPC data becomes accessible safely and securely through Internet. It is time for classic OPC to say GoodBye to DCOM!
.No DCOM when connecting to a classic OPC server
.No future DCOM vulnerability or hardening to worry
.Support dynamical languages (JavaScript/Python etc)
.Standard JSON data return
.No expensive corporate membership fee
.No OPC SDK needed
.Intuitive and easy-to-remember commands instead of long REST API URL
.Built-in account authentication by IIS
.Built-in secure connection by IIS
.Native mobile APP development feasible
.No tedious 1250-page OPC UA documents to consult
.No OPC UA certificate configuration
.No OPC UA firewall configuration
.No OPC DA->UA conversion needed
.Cross-platform in client gurantted(Linux/Mac/Windows)
.Edge or Gateway deployment ready without any expensive custom hardware
2. WebSocket feature for IIS need be enabled in the same server box
3. Microsoft VC++ Runtim for X64 required (download here and install it if needed)
Download all files from server folder to your desired one. Launch a command line with administrator privilege and enter to your download folder. Run command "install.bat userAccount userPassword" to complete installation. userAccount/userPassword need be replaced with your own Windows account/password and make sure that account has administrator privilege. This account is only used by IIS to configure a new app pool and not used by this solution or stored anywhere else. If you have previous installation, uninstall it first.
To verify, launch browser (Chrome/Safari/Edge) and enter URL "http://localhost/OPC/websocket.html"
If installed in a multiple server environment, a config file under program data folder is available to specify your desired server based on its prog ID
Run command "uninstall.bat" in command line with administrator privilege in your download folder.
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DA commands
1.1 Browse
"browse" - Show all child tags under top level of DA server
"browse:tagID" - Show all child tags under a parent tag of DA server
"browse:tagID -countsInPagenation -pageNumber" - Show a subset of children tags based on pagenation under a specific tag in DA server. For example, if there are total 10,000 children tags under a specific tag, command "browse: tagID -2000 -3" will only display a tag's 2000 children tags (4000th to 5999th) for 3rd page in DA server
JSON returns {"parentNodeID":[{"n": "tagName1", "i": "tagID1", "b": 1}, {"n": "tagName2", "i": "tagID2", "b": 0}, ...]}
(parentNodeID - parent node id or "" at top level, n - name, i - ID, b - branch)When command "browse: Random" is sent, response will be like
1.2 Read
"read: tagID1, tagID2, ..."- Read tag latest values from DA server
JSON returns {"DA":[{"i": "tagID1", "v": "20.308", "t": 1643759756112, "q": 192}, {"i": "tagID2", "v": "4", "t": 1643769859342, "q": 192}, ...]}
(i - ID, v - value, t - time stamp in milliseconds of epoch UTC, q - quality)When command "read: Random.Real4, Random.Int2" is sent, response will be like
1.3 Write
"write: tagID1 -value1; tagID2 -value2; ..."- Write tag values to DA server. It is strongly recommended NOT to use this command in a production environment when Internet access is available. Contact developer to have a version without this command for production use.
No JSON return but writing status (success/failure) will be reported as info. Use read command to verify writing's success
When command "write: Bucket Brigade.Int2 -34; Random.Int2 -12" is sent, response will be like
1.4 Subscribe
"subscribe: tagID1, tagID2, ..." - Add monitored tags to DA server and receive updates when new values are available
JSON returns {"DA":[{"i": "tagID1", "v": "20.308", "t": 1643759756112, "q": 192}, {"i": "tagID2", "v": "4", "t": 1643769859342, "q": 192}, ...]}
(i - ID, v - value, t - time stamp in milliseconds of epoch UTC, q - quality)When command "subscribe:Saw-toothed Waves.Int1,Saw-toothed Waves.Int2" is sent, response will be like
1.5 Unsubscribe
"unsubscribe" - Remove all monitored tags from DA server
"unsubscribe: tagID1, tagID2, ..." - Remove specific monitored tags from DA server
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HDA commands
2.1 Browse
"browseHDA" - Show all child tags under top level of HDA server
"browseHDA:tagID" - Show all child tags under a specific tag of HDA server
"browseHDA:tagID -countsInPagenation -pageNumber" - Show a subset of children tags based on pagenation for a specific tag in HDA server. For example, if there are total 10,000 children tags under a specific tag, command "browseHDA: tagID -2000 -3" will only display a tag's 2000 children tags (4000th to 5999th) for 3rd page in HDA server.
JSON returns {"parentNodeID":[{"n": "tagName1", "i": "tagID1", "b": 1}, {"n": "tagName2", "i": "tagID2", "b": 0}, ...]}
(parentNodeID - parent node id or "" at top level, n - name, i - ID, b - branch)When command "browseHDA: Random" is sent, response will be like
2.2 ReadRaw
"readRaw: tagID1, tagID2,..., tagIDx -startTimeStamp -endTimeStamp" - Read tags' history raw data based on start and end time stamps
JSON returns {"HDA":[{"tagID1":[{"v":"24201","t":1665632091123,"q":262336}, {"v":"19168","t":1665632092334,"q":262336},...]}, {"tagID2":[{"v":"24","t":1665632091445,"q":262336}, {"v":"168","t":1665632092667,"q":262336},...]}]}
(v - value, t - time stamp in milliseconds of epoch UTC, q - quality which need be parsed with OPC HDA and DA masks to have results like Raw/Interpolated and Good/Bad)When command "readRaw: Saw-toothed Waves.Int1,Saw-toothed Waves.Int2 -1672977528112 -1672977529338" is sent, response will be like
2.3 ReadAtTime
"readAtTime: tagID1, tagID2, ..., tagIDx -timeStamp1 -timsStamp2 -timeStampX" - Read tags' history data based on various time stamps
JSON returns {"HDA":[{"tagID1":[{"v":"24201","t":1665632091231,"q":262336}, {"v":"19168","t":1665632092354,"q":262336},...]}, {"tagID2":[{"v":"24","t":1665632091341,"q":262336}, {"v":"168","t":1665632092321,"q":262336},...]}]}
(v - value, t - time stamp in milliseconds of epoch UTC, q - quality which need be parsed with OPC HDA and DA masks to have results like Raw/Interpolated and Good/Bad)When command "readAtTime: Saw-toothed Waves.Int1,Saw-toothed Waves.Int2 -1672978265112 -1672978266338" is sent, response will be like
2.4 readModified
"readModified: tagID1, tagID2,..., tagIDx -startTimeStamp -endTimeStamp" - Read tags' modified history data based on start and end time stamps
JSON returns {"HDA":[{"tagID1":[{"v":"24201","t":1665632091231,"q":262336}, {"v":"19168","t":1665632092354,"q":262336},...]}, {"tagID2":[{"v":"24","t":1665632091341,"q":262336}, {"v":"168","t":1665632092321,"q":262336},...]}]}
(v - value, t - time stamp in milliseconds of epoch UTC, q - quality which need be parsed with OPC HDA and DA masks to have results like Raw/Interpolated and Good/Bad)2.5 ReadProcessed
"readProcessed: tagID1, tagID2,..., tagIDx -startTimeStamp -endTimeStamp -intervalInMilliseconds -aggregate" - Read tags' history processed data based on start and end time stamps at an interval for an aggregate feature
JSON returns {"HDA":[{"tagID1":[{"v":"24201","t":1665632091231,"q":262336}, {"v":"19168","t":1665632092354,"q":262336},...]}, {"tagID2":[{"v":"24","t":1665632091341,"q":262336}, {"v":"168","t":1665632092321,"q":262336},...]}]}
(v - value, t - time stamp in milliseconds of epoch UTC, q - quality which need be parsed with OPC HDA and DA masks to have results like Raw/Interpolated and Good/Bad)When command "readProcessed: random.Int1,random.Int4 -1705350325000 -1705350425000 -5000 -10" is sent, response will be like
2.6 InsertReplace
"insertReplace: tagID1 -value -timeStamp -quality;tagID2 -value -timeStamp -quality;..." - Insert or replace tags' history data and quality for specific time stamps in epoch milliseconds
No JSON returns except an operation status message
When command "insertReplace: Bucket Brigade.Int1 -234 -1710719956000 -192; Bucket Brigade.Int4 -567 -1710720852000 -192" is sent, response will be like
2.7 DeleteAtTime
"deleteAtTime: tagID1, tagID2,..., tagIDX -timeStamp1 -timeStamp2 ... -timeStampX" - Delete tags' history data based on various time stamps in epoch milliseconds
No JSON returns except an operation status message
When command "deleteAtTime: Write Error.Int1, Bucket Brigade.Int1 -1713118247000 -1713116556000" is sent, response will be like
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AE commands
3.1 Subscribe
"subscribeAE" - Receive notification on alarms and events
JSON returns {"AE":[{"s":"tagName1","m":"tagName1 Deviation is Low","c":"DEVIATION","sc":"LO","t":1643760803334,"q":192,"tp":4,"ec":2,"st":200,"a":1,"at":""}, {"s":"tagName2","m":"tagName2 Limit is Normal","c":"PVLEVEL","sc":"HIHI","t":1643760808112,"q":192,"tp":4,"ec":1,"st":500,"a":1,"at":""}]}
(s - source, m - message, c - condition, sc - sub condition, t - time stamp in milliseconds of epoch UTC, q - quality, tp - type, ec - category, st - severity, a - acknowledgement, at - actor)When command "subscribeAE" is sent, response will be like
3.2 Unsubscribe
"unsubscribeAE" - Remove notification on alarms and events
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Disconnect
"disconnect" - Close connection with server
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Help
"help" or "?" - Display all supported commands and usages
RecordIt-C32C9C56-5A8F-4BDE-B100-E520E731FCEC.mp4
OLEDB4OPC, the fastest way to transfer OPC data to database!