Docs / Yamcs HTTP API / Parameter Values / List Parameter Data

List Parameter Data

List the history of values for the specified parameter:

GET /api/archive/:instance/parameters/:namespace/:name

Parameters

Name Type Description
start string Filter the lower bound of the parameter's generation time. Specify a date string in ISO 8601 format
stop string Filter the upper bound of the parameter's generation time. Specify a date string in ISO 8601 format
norepeat bool Whether to filter out consecutive identical values. Default no.
pos integer The zero-based row number at which to start outputting results. Default: 0
limit integer The maximum number of returned records per page. Choose this value too high and you risk hitting the maximum response size limit enforced by the server. Default: 100
order string The order of the returned results. Can be either asc or desc. Default: desc
norealtime boolean Disable loading of parameters from the parameter cache. Default: false
processor string The name of the processor from which to use the parameter cache. Default: realtime
source string Specifies how to retrieve the parameters. Either ParameterArchive or replay. If replay is specified, a replay processor will be created and data will be processed with the active XTCEDB. Note that this is much slower than receiving data from the ParameterArchive.
Default: ParameterArchive

The pos and limit allow for pagination. Keep in mind that in-between two requests extra data may have been recorded, causing a shift of the results. This generic stateless operation does not provide a reliable mechanism against that, so address it by overlapping your pos parameter with rows of the previous query. In this example we overlap by 4:

?pos=0&limit=50&order=desc
?pos=45&limit=50&order=desc 

When using CSV output some columns are hidden by default. You can add them via the extra flag:

Name Type Description
extra array of strings Extra columns added to the CSV output:
  • raw: Raw parameter values
  • monitoring: Monitoring status
Example: ?extra=raw,monitoring

Response

Status: 200 OK
{
  "parameter" : [ {
    "id" : {
      "name" : "BatteryVoltage2",
      "namespace" : "/YSS/SIMULATOR"
    },
    "rawValue" : {
      "type" : "UINT32",
      "uint32Value" : 144
    },
    "engValue" : {
      "type" : "UINT32",
      "uint32Value" : 144
    },
    "acquisitionTime" : 1447417449218,
    "generationTime" : 1447417432121,
    "acquisitionStatus" : "ACQUIRED",
    "processingStatus" : true,
    "monitoringResult" : "IN_LIMITS",
    "acquisitionTimeUTC" : "2015-11-13T12:23:33.218Z",
    "generationTimeUTC" : "2015-11-13T12:23:16.121Z",
    "expirationTime" : 1447417456218,
    "expirationTimeUTC" : "2015-11-13T12:23:40.218Z",
    "alarmRange" : [ {
      "level" : "WATCH",
      "minInclusive" : 50.0
    }, {
      "level" : "WARNING",
      "minInclusive" : 40.0
    }, {
      "level" : "DISTRESS",
      "minInclusive" : 30.0
    }, {
      "level" : "CRITICAL",
      "minInclusive" : 20.0
    }, {
      "level" : "SEVERE",
      "minInclusive" : 10.0
    } ]
  } ]
}

Alternative Media Types

CSV

Use HTTP header:

Accept: text/csv

Or, add this query parameter: format=csv.

Status: 200 OK
Content-Type: text/csv
Time    BatteryVoltage2
2015-11-13T12:21:55.199 157
2015-11-13T12:21:48.972 158
2015-11-13T12:21:42.750 159                       

Protobuf

Use HTTP header:

Accept: application/protobuf

Response is of type:

pvalue/pvalue.proto 
message ParameterData {
  repeated ParameterValue parameter = 1;
}