Stream GetChannel

Opens a channel that will send messages about any value changes for the specified stream. See Channels for more information.

Request

GET streams/{webId}/channel

URL Parameters

• webId

  The ID of the stream.See WebID for more information.

• includeInitialValues

  Specified if the channel should send a message with the current value of the stream after the connection is opened. The default is 'false'.

• heartbeatRate

  HeartbeatRate is an integer multiple of the Polling Interval.See Channels for more information. It specifies the rate at which a client will receive an empty message if there are no data updates. It can be used to check that the connection is still alive. Zero/negative values correspond to no heartbeat. By default, no empty messages will be sent to the user.

• webIdType

  Optional parameter. Used to specify the type of WebID. Useful for URL brevity and other special cases. Default is the value of the configuration item "WebIDType". See WebID Type for more information.

Status Codes

101: Switches to the Web Socket protocol.

Sample Response Body

{
  "Items": [
    {
      "WebId": "I1AbEDqD5loBNH0erqeqJodtALAYIKyyz2F5BGAxQAVXYRDBAGyPedZG1sUmxOOclp3Flwg",
      "Name": "Water",
      "Path": "\\\\MyAssetServer\\MyDatabase\\MyElement|Water",
      "Items": [
        {
          "Timestamp": "2014-07-22T14:00:00Z",
          "UnitsAbbreviation": "m",
          "Good": true,
          "Questionable": false,
          "Substituted": false,
          "Annotated": false,
          "Value": 12.3
        },
        {
          "Timestamp": "2014-07-22T14:00:00Z",
          "UnitsAbbreviation": "m",
          "Good": true,
          "Questionable": false,
          "Substituted": false,
          "Annotated": false,
          "Value": 12.3
        }
      ],
      "UnitsAbbreviation": "m",
      "Links": {
        "Self": "https://localhost.osisoft.int/piwebapi/attributes/I1AbEDqD5loBNH0erqeqJodtALAYIKyyz2F5BGAxQAVXYRDBAGyPedZG1sUmxOOclp3Flwg"
      }
    },
    {
      "WebId": "I1AbEDqD5loBNH0erqeqJodtALAYIKyyz2F5BGAxQAVXYRDBAGyPedZG1sUmxOOclp3Flwg",
      "Name": "Water",
      "Path": "\\\\MyAssetServer\\MyDatabase\\MyElement|Water",
      "Items": [
        {
          "Timestamp": "2014-07-22T14:00:00Z",
          "UnitsAbbreviation": "m",
          "Good": true,
          "Questionable": false,
          "Substituted": false,
          "Annotated": false,
          "Value": 12.3
        },
        {
          "Timestamp": "2014-07-22T14:00:00Z",
          "UnitsAbbreviation": "m",
          "Good": true,
          "Questionable": false,
          "Substituted": false,
          "Annotated": false,
          "Value": 12.3
        }
      ],
      "UnitsAbbreviation": "m",
      "Links": {
        "Self": "https://localhost.osisoft.int/piwebapi/attributes/I1AbEDqD5loBNH0erqeqJodtALAYIKyyz2F5BGAxQAVXYRDBAGyPedZG1sUmxOOclp3Flwg"
      }
    }
  ],
  "Links": {}
}