Artwork by Ashley McNamara
Inspired by Renee French
Taken from https://gopherize.me by Mat Ryer

OPC/UA

A native Go implementation of the OPC/UA Binary Protocol.

We support the current and previous major Go release. See below for a list of Tested Platforms and Supported Features.

v0.5.x BREAKING CHANGES

• v0.5.0 released on 14 Aug 2023: all Client methods must have a context
• v0.5.1 released on 22 Aug 2023: the NewClient function returns an error

In v0.3.0 on 21 Jan 2022 release we added WithContext variants for all methods to avoid a breaking change. All existing methods without a context had a disclaimer that with v0.5.0 their signature would change to include the context and that the WithContext method would be removed.

We missed to update the NewClient function in v0.5.0 which was fixed in v0.5.1.

Please update your code and let us know if there are any issues!

Thank you!

Your GOPCUA Team

Quickstart

# install library
go get -u github.com/zheleziv/opcua

# get current date and time 'ns=0;i=2258'
go run examples/datetime/datetime.go -endpoint opc.tcp://localhost:4840

# read the server version
go run examples/read/read.go -endpoint opc.tcp://localhost:4840 -node 'ns=0;i=2261'

# get the current date time using different security and authentication modes
go run examples/crypto/*.go -endpoint opc.tcp://localhost:4840 -cert path/to/cert.pem -key path/to/key.pem -sec-policy Basic256 -sec-mode SignAndEncrypt

# checkout examples/ for more examples...

Sponsors

The gopcua project is sponsored by the following organizations by supporting the active committers to the project:

Users

We would also like to list organizations which use gopcua in production. Please open a PR to include your logo below.

Projects using gopcua

gopcua is not only utilized in production environments, but it also serves as a critical component in other larger projects. Here are some projects that rely on gopcua for their functionality:

• Telegraf: This plugin-driven server agent is used for collecting and sending metrics. It leverages gopcua to extract data from OPC-UA servers and insert it into InfluxDB. Telegraf supports both polling and subscribing methods for data acquisition.
• benthos-umh: This project is built upon the benthos stream-processing framework. It utilizes gopcua to extract data from OPC-UA servers and forwards the information to MQTT or Kafka brokers. benthos-umh currently supports polling for data collection.

Disclaimer

We are still actively working on this project and the APIs will change.

However, you can safely assume that we are aiming to make the APIs as stable as possible since the code is in use in several large scale production environments.

The Current State was moved to the Wiki.

Your Help is Appreciated

If you are looking for ways to contribute you can

• test the high-level client against real OPC/UA servers
• add functions to the client or tell us which functions you need for gopcua to be useful
• work on the security layer, server and other components
• and last but not least, file issues, review code and write/update documentation

Also, if the library is already useful please spread the word as a motivation.

Tested Platforms

gopcua is run in production by several companies and with different equipment. The table below is an incomplete list of where and how gopcua is used to provide some guidance on the level of testing.

We would be happy if you can add your equipment to the list. Just open a PR :)

Device	gopcua version	Environment	By
Siemens S7-1500	v0.1.x..latest	production	Northvolt
Beckhoff C6015-0010,C6030-0060 on OPC/UA server 4.3.x	v0.1.x..latest	production	Northvolt
Kepware 6.x	v0.1.x..latest	production	Northvolt
Kepware 6.x	v0.1.x, v0.2.x	production	Intelecy
Cogent DataHub 9.x	v0.1.x, v0.2.x	production	Intelecy
ABB Ability EdgeInsight 1.8.X	v0.1.x, v0.2.x	production	Intelecy
GE Digital Historian 2022 HDA Server	v0.3.x	production	Intelecy
B&R Automation PC 3100	v0.3.x	production	ACS
InfluxDB Telegraf plugin	v0.3.x	?	Community

Supported Features

The current focus is on the OPC UA Binary protocol over TCP. No other protocols are supported at this point.

Categories	Features	Supported	Notes
Encoding	OPC UA Binary	Yes
	OPC UA JSON		not planned
	OPC UA XML		not planned
Transport	UA-TCP UA-SC UA Binary	Yes
	OPC UA HTTPS		not planned
	SOAP-HTTP WS-SC UA Binary		not planned
	SOAP-HTTP WS-SC UA XML		not planned
	SOAP-HTTP WS-SC UA XML-UA Binary		not planned
Encryption	None	Yes
	Basic128Rsa15	Yes
	Basic256	Yes
	Basic256Sha256	Yes
Authentication	Anonymous	Yes
	User Name Password	Yes
	X509 Certificate	Yes

Services

Here is the current set of supported services. For low-level access use the client Send function directly.

Service Set	Service	Client	Notes
Discovery Service Set	FindServers	Yes
	FindServersOnNetwork	Yes
	GetEndpoints	Yes
	RegisterServer
	RegisterServer2
Secure Channel Service Set	OpenSecureChannel	Yes
	CloseSecureChannel	Yes
Session Service Set	CreateSession	Yes
	CloseSession	Yes
	ActivateSession	Yes
	Cancel
Node Management Service Set	AddNodes
	AddReferences
	DeleteNodes
	DeleteReferences
View Service Set	Browse	Yes
	BrowseNext	Yes
	TranslateBrowsePathsToNodeIds
	RegisterNodes	Yes
	UnregisterNodes	Yes
Query Service Set	QueryFirst
	QueryNext
Attribute Service Set	Read	Yes
	Write	Yes
	HistoryRead	Yes
	HistoryUpdate
Method Service Set	Call	Yes
MonitoredItems Service Set	CreateMonitoredItems	Yes
	DeleteMonitoredItems	Yes
	ModifyMonitoredItems	Yes
	SetMonitoringMode
	SetTriggering
Subscription Service Set	CreateSubscription	Yes
	ModifySubscription
	SetPublishingMode
	Publish	Yes
	Republish
	DeleteSubscriptions	Yes
	TransferSubscriptions

Authors

The Gopcua Team.

If you need to get in touch with us directly you may find us on Keybase.io but try to create an issue first.

License

MIT