com.netflix.spectator.atlas.impl

Interface DataExpr

All Known Subinterfaces:

DataExpr.AggregateFunction

All Known Implementing Classes:

DataExpr.All, DataExpr.Count, DataExpr.DropRollup, DataExpr.GroupBy, DataExpr.KeepRollup, DataExpr.Max, DataExpr.Min, DataExpr.Sum

public interface DataExpr

Data expressions for defining how to aggregate values. For more information see Atlas docs.

Classes in this package are only intended for use internally within spectator. They may change at any time and without notice.

Nested Class Summary

Nested Classes

Modifier and Type	Interface and Description
static interface	DataExpr.AggregateFunction Base type for simple aggregate functions.
static interface	DataExpr.Aggregator Helper for incrementally computing an aggregate of a set of tag values.
static class	DataExpr.All Includes all datapoints that match the query expression.
static class	DataExpr.Count Aggregates all datapoints that match the query to a single datapoint that is the number of input values.
static class	DataExpr.DropRollup Rollup inputs by dropping the specified keys.
static class	DataExpr.GroupBy Compute a set of time series matching the query and grouped by the specified keys.
static class	DataExpr.KeepRollup Rollup inputs by only keeping the specified keys.
static class	DataExpr.Max Aggregates all datapoints that match the query to a single datapoint that is the maximum of the input values.
static class	DataExpr.Min Aggregates all datapoints that match the query to a single datapoint that is the minimum of the input values.
static class	DataExpr.Sum Aggregates all datapoints that match the query to a single datapoint that is the sum of the input values.

Method Summary

Modifier and Type	Method and Description
default DataExpr.Aggregator	aggregator(boolean shouldCheckQuery) Get an aggregator that can be incrementally fed values.
DataExpr.Aggregator	aggregator(Map<String,String> tags, boolean shouldCheckQuery) Get an aggregator that can be incrementally fed values.
default Iterable<TagsValuePair>	eval(Iterable<TagsValuePair> input) Evaluate the data expression over the input.
boolean	isAccumulating() Returns true if the aggregation type is accumulating (sum or count).
default boolean	isCount() Returns true if the aggregation type is count.
Query	query() Query for selecting the input measurements that should be aggregated.
Map<String,String>	resultTags(Map<String,String> tags) Get the set of result tags for a particular datapoint.

Method Detail

query

Query query()

Query for selecting the input measurements that should be aggregated.

isAccumulating

boolean isAccumulating()

Returns true if the aggregation type is accumulating (sum or count).

isCount

default boolean isCount()

Returns true if the aggregation type is count.

resultTags

Map<String,String> resultTags(Map<String,String> tags)

Get the set of result tags for a particular datapoint. The result tags will include everything with an exact match in the query clause and keys used in a group by clause.

Parameters:

tags - Full set of tags for a datapoint.

Returns:

Result tags for a datapoint.

aggregator

DataExpr.Aggregator aggregator(Map<String,String> tags,
                               boolean shouldCheckQuery)

Get an aggregator that can be incrementally fed values. See eval(Iterable) if you already have the completed list of values.

Parameters:

tags - The set of tags for the final aggregate.

shouldCheckQuery - If true, then values will be checked against the query before applying to the aggregate. Otherwise, it is assumed that the user has already verified that the datapoint matches before passing it in.

Returns:

Aggregator for this data expression.

aggregator

default DataExpr.Aggregator aggregator(boolean shouldCheckQuery)

Get an aggregator that can be incrementally fed values. See eval(Iterable) if you already have the completed list of values.

Parameters:

shouldCheckQuery - If true, then values will be checked against the query before applying to the aggregate. Otherwise, it is assumed that the user has already verified that the datapoint matches before passing it in.

Returns:

Aggregator for this data expression.

eval

default Iterable<TagsValuePair> eval(Iterable<TagsValuePair> input)

Evaluate the data expression over the input.

Parameters:

input - Set of data values. The data will get filtered based on the query, that does not need to be done in advance.

Returns:

Aggregated data values.