OPC UA API reference

OPC UA connector programming specifications for FairCom Edge

FairCom provides special API actions for OPC UA connectors and transforms. The OPC UA service must be enabled in order to complete FairCom OPC UA actions.

Request examples

Note

The FairCom createInput JSON action is used to define the specifics of a connector device and the desired data.

Minimal example

{
  "api": "hub",
  "action": "createInput",
  "params": {
    "inputName": "opcDS1",
    "serviceName": "opcua",
    "settings": {
      "opcServerUrl": "opc.tcp://MyOPCDevice.com:4840",
      "propertyMapList": [
        {
          "propertyPath": "the_answer",
          "opcNamespace": 1,
          "opcNodeName": "the.answer"
        }
      ]
    },
    "tableName": "opcTable1"
  },
  "authToken": "replaceWithAuthTokenFromCreateSession"
}

Maximal example

{
  "requestId": "19",
  "api": "hub",
  "apiVersion": "1.0",
  "action": "createInput",
  "params": {
    "inputName": "opcDS2",
    "serviceName": "opcua",
    "dataPersistenceStrategy": "onChange", 
    "dataCollectionIntervalMilliseconds": 5000,
    "immediatelyCollectDataOnStart": true,
    "dataCollectionBufferCount": 2,
    "settings": {
      "opcServerUrl": "opc.tcp://MyOPCDevice.com:4840",
      "opcServerUser": "MyUser",
      "opcServerPassword": "MyPassword",
      "propertyMapList": [
        {
          "propertyPath": "temperature",
          "opcNamespace": 1,
          "opcNodeName": "OPC-temperature-datasource"
        },
        {
          "propertyPath": "humidity",
          "opcNamespace": 1,
          "opcNodeName": "OPC-humidity-datasource"
        },
        {
          "propertyPath": "pressure",
          "opcNamespace": 1,
          "opcNodeName": "OPC-pressure-datasource"
        },
        {
          "propertyPath": "quality",
          "opcNamespace": 1,
          "opcNodeName": "OPC-quality-datasource"
        }
      ]
    },
    "ownerName": "admin",
    "tableName": "opcTable2",
    "databaseName": "faircom",
    "retentionPolicy": "autoPurge",
    "retentionPeriod": 30,
    "retentionUnit": "day",
    "metadata": {
    }
  },
  "authToken": "replaceWithAuthTokenFromCreateSession"
}

OPC UA connector programming specifications for FairCom Edge

API referenceJSON Hub APIOPC UAOPC UA connectorOPC UA API reference

`"params"`

The "params" property is an object that contains an action's parameters. Each action defines its own required and optional properties.

Note

See createInput for "params" properties that are common to all connectors.

Table 1. OPC UA specific connector "params" properties summary

Property

Description

Default

Type

Limits (inclusive)

dataCollectionBufferCount

(optional) specifies the number of times the collector retrieves and caches data from the device before writing the data to the integration table

1

integer

1 to 65535

dataCollectionIntervalMilliseconds

(optional) specifies the number of milliseconds to wait until reading PLC data again. For example, 15000 means 15 seconds

10000

integer

0 and negative values are invalid

dataPersistenceStrategy

(optional) specifies when the connector writes collected data to the specified table

"onSchedule"

string

"onSchedule"

"onChange"

immediatelyCollectDataOnStart

(optional) configures the input to collect data immediately when the server or connector starts. This occurs even if the data persistence strategy is to collect data changes

false

Boolean

true

false

serviceName

specifies which type of input to create

string

"opcua"

settings

specifies properties needed to configure the data source of the input

array of objects

settings

.opcServerUrl

specifies the IP or URL to your OPC UA device, including the port

string

settings

.opcServerUser

(optional) specifies the username for your OPC UA device

""

string

settings

.opcServerPassword

(optional) specifies the password for your OPC UA device

""

string

settings

.propertyMapList

specifies properties that represent the data being requested

array of objects

settings

.propertyMapList

.propertyPath

specifies the JSON path in the JSON document where the connector puts the data it collects. It is the tag name of the data being collected

string

JSON path

settings

.propertyMapList

.opcNamespace

specifies the OPC UA namespace that this variable exists in

int16

0 to 32767

settings

.propertyMapList

.opcNodeName

specifies the name of the OPC UA variable for this data

string

`"propertyPath"`

The "propertyPath" property is a required string that specifies the JSON Path in the JSON document where the connector puts the data it collects. It is the tag name of the data being collected. You can use this property to take collected data and store it in any location in the JSON document generated by the connector. For example, the setting "propertyPath": "temperature" causes the server to take a value it collects, such as 20.1, and store it in a "temperature" property, such as { "temperature": 20.1 }.

`"settings"`

The "settings" property is an array of objects that contains properties needed to configure the data source of the input. It is required and has no default.

Property summary

Table 2. "settings" property summaries

Property	Description	Default	Type	Limits
opcServerUrl	contains the IP or URL to your OPC UA device, including the port	Required - No default value	string
opcServerUser	contains the username for your OPC UA device	""	string
opcServerPassword	contains the password for your OPC UA device	""	string
opcDataCollectionIntervalMilliseconds	specifies how often the data should be requested in milliseconds. Setting it to `0` causes the data to be requested only when data values change	Required - No default value	int32	`0` to `2147483647`
propertyMapList	contains properties that represent the data being requested	Required - No default value	array of objects

`"propertyMapList"`

The "propertyMapList" property is an array of objects that contains properties that represent the data being requested. It is required and has no default.

Property summary

Table 3. "propertyMapList" property summaries

Property	Description	Default	Type	Limits
propertyPath	specifies the JSON property that this data will be identified by	Required - No default value	string
opcNamespace	specifies the OPC UA namespace that this variable exists in	Required - No default value	int16	`0` to `32767`
opcNodeName	specifies the name of the OPC UA variable for this data	Required - No default value	string