本地英文版地址: ../en/rollup-get-rollup-index-caps.html
Get rollup index capabilities APIedit
Returns the rollup capabilities of all jobs inside of a rollup index (e.g. the index where rollup data is stored).
This functionality is experimental and may be changed or removed completely in a future release. Elastic will take a best effort approach to fix any issues, but experimental features are not subject to the support SLA of official GA features.
Requestedit
GET <index>/_rollup/data
Prerequisitesedit
-
If the Elasticsearch security features are enabled, you must have the
readindex privilege on the index that stores the rollup results. For more information, see Security privileges.
Descriptionedit
A single rollup index may store the data for multiple rollup jobs, and may have a variety of capabilities depending on those jobs.
This API will allow you to determine:
- What jobs are stored in an index (or indices specified via a pattern)?
- What target indices were rolled up, what fields were used in those rollups and what aggregations can be performed on each job?
Path parametersedit
-
<index> - (Required, string) Index or index-pattern of concrete rollup indices to check for capabilities.
Examplesedit
Imagine we have an index named sensor-1 full of raw data. We know that the
data will grow over time, so there will be a sensor-2, sensor-3, etc.
Let’s create a rollup job that stores its data in sensor_rollup:
PUT _rollup/job/sensor
{
"index_pattern": "sensor-*",
"rollup_index": "sensor_rollup",
"cron": "*/30 * * * * ?",
"page_size" :1000,
"groups" : {
"date_histogram": {
"field": "timestamp",
"fixed_interval": "1h",
"delay": "7d"
},
"terms": {
"fields": ["node"]
}
},
"metrics": [
{
"field": "temperature",
"metrics": ["min", "max", "sum"]
},
{
"field": "voltage",
"metrics": ["avg"]
}
]
}
If at a later date, we’d like to determine what jobs and capabilities were
stored in the sensor_rollup index, we can use the get rollup index API:
GET /sensor_rollup/_rollup/data
Note how we are requesting the concrete rollup index name (sensor_rollup) as
the first part of the URL. This will yield the following response:
{
"sensor_rollup" : {
"rollup_jobs" : [
{
"job_id" : "sensor",
"rollup_index" : "sensor_rollup",
"index_pattern" : "sensor-*",
"fields" : {
"node" : [
{
"agg" : "terms"
}
],
"temperature" : [
{
"agg" : "min"
},
{
"agg" : "max"
},
{
"agg" : "sum"
}
],
"timestamp" : [
{
"agg" : "date_histogram",
"time_zone" : "UTC",
"fixed_interval" : "1h",
"delay": "7d"
}
],
"voltage" : [
{
"agg" : "avg"
}
]
}
}
]
}
}
The response that is returned contains information that is similar to the original rollup configuration, but formatted differently. First, there are some house-keeping details: the rollup job ID, the index that holds the rolled data, the index pattern that the job was targeting.
Next it shows a list of fields that contain data eligible for rollup searches.
Here we see four fields: node, temperature, timestamp and voltage. Each
of these fields list the aggregations that are possible. For example, you can
use a min, max, or sum aggregation on the temperature field, but only a
date_histogram on timestamp.
Note that the rollup_jobs element is an array; there can be multiple,
independent jobs configured for a single index or index pattern. Each of these
jobs may have different configurations, so the API returns a list of all the
various configurations available.
Like other APIs that interact with indices, you can specify index patterns instead of explicit indices:
GET /*_rollup/_rollup/data