OPC UA Browse

Overview

You can use this Snap to browse the node hierarchy of a connected OPC UA server. It navigates the OPC UA server’s address space to discover nodes and hierarchy and apply filters to refine the results.


OPC UA Browse Overview

Snap views

View Description Examples of upstream and downstream Snaps
Input This Snap has one document input view.
Output This Snap has one document output view. It retreives child nodes, their attributes, and references.
Error

Error handling is a generic way to handle errors without losing data or failing the Snap execution. You can handle the errors that the Snap might encounter when running the pipeline by choosing one of the following options from the When errors occur list under the Views tab. The available options are:

  • Stop Pipeline Execution Stops the current pipeline execution when an error occurs.
  • Discard Error Data and Continue Ignores the error, discards that record, and continues with the remaining records.
  • Route Error Data to Error View Routes the error data to an error view without stopping the Snap execution.

Learn more about Error handling in Pipelines.

Snap settings

Legend:
  • Expression icon (): Allows using JavaScript syntax to access SnapLogic Expressions to set field values dynamically (if enabled). If disabled, you can provide a static value. Learn more.
  • SnapGPT (): Generates SnapLogic Expressions based on natural language using SnapGPT. Learn more.
  • Suggestion icon (): Populates a list of values dynamically based on your Snap configuration. You can select only one attribute at a time using the icon. Type into the field if it supports a comma-separated list of values.
  • Upload : Uploads files. Learn more.
Learn more about the icons in the Snap settings dialog.
Field / Field set Type Description
Label String

Required. Specify a unique name for the Snap. Modify this to be more appropriate, especially if more than one of the same Snaps is in the pipeline.

Default value: OPC UA Browse

Example: Browse data
Starting node ID String/Expression

Required. Specify the node ID from which the browsing should start.

Default value: N/A

Example: ns=0;i=85
Browse direction Dropdown list/Expression
Required. Choose the direction for browsing the node hierarchy. Available options are:
  • Forward
  • Inverse
  • Both: If browse direction is both, depth must be either 0 or 1.

It supports recursive browsing to explore the entire address space.

Default value: Forward

Example: Both
Depth Integer/Expression
Required. Specify the maximum number of levels to recursively browse from the starting node. Depth is restricted to 0-1 if Browse direction is Both for recursive browsing.
Note: For unlimited browsing depth, use -1 as the value.

Default value: 1

Example: 3
Reference type filter String/Expression

Specify the reference type to filter the nodes.

Default value: N/A

Example: Organizes, HasComponent
Include subtypes Checkbox/Expression

Appears when you enable Reference type filter field.

Select this checkbox to include subtypes of the selected reference type in the results.

Default status: Selected
Node class filters Use this field set to filter the node types based on node classes such Object and Variable.
Node class filter String/Expression/ Suggestion

Specify or select the type of node class filter to include in the results.

  • Object
  • Variable
  • Method
  • ReferenceType
  • DataType
Note: When the Depth is greater than 1, and if you select only the target node class (e.g., Variable, ObjectType) in the Node class filter, the Snap does not return the nodes nested under Object or Method nodes. This is because the traversal requires matching NodeClasses at each level to continue.

Workaround: To get the deeper level variables, you must specify the parent node class in the Node class filter field.

For example, if you want to get the Variable nodes located at deeper levels from the Variable Node Class when the Depth is more than 1, then specify the parent Node Classes (such as Object or Method) also in the filter.

Default value: N/A

Example: Variable
Max references per node Integer/Expression

Specify the maximum number of references to return per node. A node refers to any item within a UA server, including tags and folders. A reference, on the other hand, is a link to another node.

This setting is useful in scenarios where the address space is completely flat, as a large number of adjacent nodes may exceed the maximum message size. In such cases, increasing this property’s value can be beneficial. However, most systems do not require changes to this setting.

Default value: N/A

Example: 100
Snap execution Dropdown list
Choose one of the three modes in which the Snap executes. Available options are:
  • Validate & Execute: Performs limited execution of the Snap and generates a data preview during pipeline validation. Subsequently, performs full execution of the Snap (unlimited records) during pipeline runtime.
  • Execute only: Performs full execution of the Snap during pipeline execution without generating preview data.
  • Disabled: Disables the Snap and all Snaps that are downstream from it.

Default value: Validate & Execute

Example: Execute