public class PeriodicSequence extends PTransform<PCollection<PeriodicSequence.SequenceDefinition>,PCollection<Instant>>
PTransform
which generates a sequence of timestamped elements at given runtime
intervals.
Transform assigns each element some timestamp and will only output element when worker clock reach given timestamp. Transform will not output elements prior to target time. Transform can output elements at any time after target time.
Modifier and Type | Class and Description |
---|---|
static class |
PeriodicSequence.OutputRangeTracker |
static class |
PeriodicSequence.SequenceDefinition |
name, resourceHints
Modifier and Type | Method and Description |
---|---|
static PeriodicSequence |
create() |
PCollection<Instant> |
expand(PCollection<PeriodicSequence.SequenceDefinition> input)
Override this method to specify how this
PTransform should be expanded on the given
InputT . |
compose, compose, getAdditionalInputs, getDefaultOutputCoder, getDefaultOutputCoder, getDefaultOutputCoder, getKindString, getName, getResourceHints, populateDisplayData, setResourceHints, toString, validate, validate
public static PeriodicSequence create()
public PCollection<Instant> expand(PCollection<PeriodicSequence.SequenceDefinition> input)
PTransform
PTransform
should be expanded on the given
InputT
.
NOTE: This method should not be called directly. Instead apply the PTransform
should
be applied to the InputT
using the apply
method.
Composite transforms, which are defined in terms of other transforms, should return the output of one of the composed transforms. Non-composite transforms, which do not apply any transforms internally, should return a new unbound output and register evaluators (via backend-specific registration methods).
expand
in class PTransform<PCollection<PeriodicSequence.SequenceDefinition>,PCollection<Instant>>