ProcessValues

Description

Retrieves a set of process value records (where each record includes value + time + quality, or VTQ) for the specified tags.

URL

/ProcessValues

Method

GET 

Required Parameters

• FQN=[string ]
  The fully qualified name for the tag. A fully qualified name uses the format: datasource.tagname.

• DateTime=[DateTimeOffset ]
  (v2 and later) Specified in UTC using the RFC3339 / ISO8601 format with the Z time zone designator. For example: 2016-09-03T18:44:09.352247Z.

Optional Parameters

• OPCQuality =[Int32 ]
  The data quality as reported by the source.

• Value =[Double ]
  0 or 1.

• Text=[String ]
  For string tags, contain the value.

  For discrete tags, contains the message associated the value (0 or 1).

Success Response

Code: 200 
Content: { fqn: plant12.pump6, datetime: 2016-09-03T18:44:09.352247Z}

Error Response

Code: 404 NOT FOUND 
Content: { error : "FQN doesn't exist" }

or

Code: 401 UNAUTHORIZED 
Content: { error : "You are unauthorized to make this request." }

Sample Query

Scenario 1

This query produces process values for a list of tags that end with "level". In this case, the user doesn't know the fully qualified name (FQN) of a specific tag and wants a short list of possible matches.

https://online.wonderware.[DOMAINSUFFIX]/apis/historian/v2/ProcessValues
?TagFilter=endswith(FQN, 'level').

See more TagFilter examples.

Scenario 2

This query returns process values for a specific tag identified by its fully qualified name (datasource.tagname). Using a"$filter" clause, it specifies a tag named tank_level within the Baytown data source. The result is a list of values for the tank_level tag.

https://online.wonderware.[DOMAINSUFFIX]/s/ik97r5/apis/historian/v2/ProcessValues
?$filter=FQN+eq+'Baytown.tank_level'

Scenario 3

This query includes a start date time, end date time, and other query parameters.

https://online.wonderware.[DOMAINSUFFIX]/s/ik97r5/apis/historian/v2/ProcessValues
?$filter=FQN+eq+'Baytown.tank_level'and DateTime ge 2014-07-04T23:57:29Z
and DateTime le 2014-07-05T00:02:29Z&RetrievalMode=BestFit&Resolution=6500

Sample Output

{

"odata.metadata": "https://online.wonderware.[DOMAINSUFFIX]/s/ik97r5/apis/historian/v2/
$metadata#ProcessValues",

"value": [

{

"FQN": "20140805AK.TestSkipToken_0",

"DateTime": "2014-08-06T17:25:19.216486Z",

"OpcQuality": 192,

"Value": 39816,

"Text": "39816"

},

{

"FQN": "20140805AK.TestSkipToken_0",

"DateTime": "2014-08-06T17:25:20.196Z",

"OpcQuality": 192,

"Value": 39817,

"Text": "39817"

}

],

}