Configuration Properties for OPC-UA Protocol Adapter

OPC-UA configurations are stored in the opcua block, and there are four different types:

The following fields are common among all four block types: transport_addr, data_map, log_level, log_name, trace_level and options.

`transport_addr`

The transport_addr field determines the location of the OPC-UA endpoint the block will communicate with. Its prefix can be any of the following:


Possible prefixes
'opc-tcp'

`data_map`

An array of objects. Each object has a type key and an alias key. The top-level key is the address of the tag to be written on the OPC-UA server, in OPC-UA XML Notation.

The type value is the data type to be written. It corresponds to one of the types described in Key Concept - Flat JSON format.
The alias value is an array of strings. If the string "X" is in alias, then any JSON in flat JSON format received where data.X is a key will have data.X.val written to the OPC-UA server.

Note: The data_map field's structure is different for the OPC-UA Sub/Poll Flat and the OPC-UA Sink Flat blocks. To see the structure for each block, see that block's section below.

`log_level` and `log_name`

For details about the log_level and log_name fields, see the Generic CDP Blocks section of the Protocol Adapters documentation page.

`trace_level`

The trace_level enables logging for the underlying client that connects to the OPC-UA device. It should be set once for the adapter and will affect every OPC-UA block (poll, subscription, etc.) in the configuration file. When used multiple times, the first trace_level encountered will be used. The default value is none.


Possible Values
`content`, `debug`, `info`, `warning`, `error`, `none`

`options`


Field	Type	Required	Default	Description
username	String	yes if using username/password authentication		Username for OPC-UA username/password authentication
password	String	yes if using username/password authentication		Password for private key in `client_private_key_path`when using certificate authentication or `username`when using username/password authentication
client_private_key_path	String			Path to the private key for OPC-UA certificate authentication. This private key should be kept secret and not moved to any other server. Interchangeable with `user_private_key_path`.
client_cert_path	String			Path to the public certificate for OPC-UA certificate authentication. The file at this path should be added to your OPC-UA server’s trust store. Interchangeable with `user_cert_path`.
user_cert_path	String			Path to the public certificate this client uses for user authentication. Only DER encoded files are currently supported. The certificate should match with the private key specified by user_private_key_path. Interchangeable with `client_cert_path.`
user_private_key_path	String			Path to the private key this client uses for user certificate. Only PEM encoded private keys are supported. Interchangeable with `client_private_key_path`
user_cert_password	String			Password to the private key this client uses for user certificate. Only PEM encoded private keys are supported.
encryption_cert_path	String			Path to the public certificate this client uses for encrypted connection. Only DER encoded files are currently supported. The certificate should match with the private key specified by `encryption_private_key_path`.
encryption_private_key_path	String			Path to the private key this client uses for encrypted connection. Only PEM encoded private keys are supported.
encryption_cert_password	String			Password to the private key this client uses for encrypted connection. Only PEM encoded private keys are supported.
application_uri	String		urn:ge.edge.research.com:GEPredix:OPCUAClient	The application URI for this client. Must match the URI in the client’s encryption certificate.
pki_root_path	String			The path where the client PKI structure is created if encryption connection is used. Only applies if encryption certificate is used.
security_mode	String			Specifies the security policy to use for encrypted connection. Only applies if encryption certificate is used.
session_timeout	Integer		1200000 (20 minutes)	Indicates how long, in milliseconds, the server will retain a connection without receiving a message from the client.
connect_timeout	Integer		5000	The length of time, in milliseconds, a client will wait for a reply to a connect request.
watchdog_interval	Integer		5000	The number of milliseconds between watchdog checks.
watchdog_timeout	Integer		5000	The maximum amount of time, in milliseconds, a client will wait for a response to a watchdog request. After the first failure, the watchdog timeout doubles; after a second failure, the connection ends.
publishing_interval	Integer		1000	Controls how often, in milliseconds, the client will check for available data (to which the client is subscribed). Note: Used only by blocks that support subscription.
sampling_interval	Integer		200	Controls how often, in milliseconds, the server samples the value of a tag. Note: Valid only for OPC-UA adapters that subscribe to tags (otherwise the option is ignored).
lifetime_count	Integer		1200	Controls the lifetime, in seconds, of the subscription (as opposed to the lifetime of the session). The lifetime of the subscription is set to publishing interval * lifetime count. The default is 1200 (20 minutes). Note: Used only by blocks that support subscription.
max_batch_size	Integer		200	The maximum number of tags that can be subscribed to in a single network request. For example, an adapter with 1000 tags and a max_batch_size of 200 would send five network requests. Note: Used only by blocks that support subscription.
max_nodes_per_sub	Integer		800	The maximum number of subscription tags that can be associated with a single subscription. Once this limit is reached, a new subscription is created. Note: Valid only for OPC-UA adapters that subscribe to tags (otherwise the option is ignored).
queue_size	Integer		1	The number of data samples queued for publication. Used when the sampling interval is less than the publishing interval. A value of 0 or 1 results in only the most recent value being published. Note: Valid only for OPC-UA adapters that subscribe to tags (otherwise the option is ignored).