71 lines
1.8 KiB
Go
71 lines
1.8 KiB
Go
/*
|
|
Copyright 2015 The Kubernetes Authors.
|
|
|
|
Licensed under the Apache License, Version 2.0 (the "License");
|
|
you may not use this file except in compliance with the License.
|
|
You may obtain a copy of the License at
|
|
|
|
http://www.apache.org/licenses/LICENSE-2.0
|
|
|
|
Unless required by applicable law or agreed to in writing, software
|
|
distributed under the License is distributed on an "AS IS" BASIS,
|
|
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
|
See the License for the specific language governing permissions and
|
|
limitations under the License.
|
|
*/
|
|
|
|
package queue
|
|
|
|
// Decide whether a pre-existing deadline for an item in a delay-queue should be
|
|
// updated if an attempt is made to offer/add a new deadline for said item. Whether
|
|
// the deadline changes or not has zero impact on the data blob associated with the
|
|
// entry in the queue.
|
|
type DeadlinePolicy int
|
|
|
|
const (
|
|
PreferLatest DeadlinePolicy = iota
|
|
PreferEarliest
|
|
)
|
|
|
|
// Decide whether a pre-existing data blob in a delay-queue should be replaced if an
|
|
// an attempt is made to add/offer a new data blob in its place. Whether the data is
|
|
// replaced has no bearing on the deadline (priority) of the item in the queue.
|
|
type ReplacementPolicy int
|
|
|
|
const (
|
|
KeepExisting ReplacementPolicy = iota
|
|
ReplaceExisting
|
|
)
|
|
|
|
func (rp ReplacementPolicy) replacementValue(original, replacement interface{}) (result interface{}) {
|
|
switch rp {
|
|
case KeepExisting:
|
|
result = original
|
|
case ReplaceExisting:
|
|
fallthrough
|
|
default:
|
|
result = replacement
|
|
}
|
|
return
|
|
}
|
|
|
|
func (dp DeadlinePolicy) nextDeadline(a, b Priority) (result Priority) {
|
|
switch dp {
|
|
case PreferEarliest:
|
|
if a.ts.Before(b.ts) {
|
|
result = a
|
|
} else {
|
|
result = b
|
|
}
|
|
case PreferLatest:
|
|
fallthrough
|
|
default:
|
|
if a.ts.After(b.ts) {
|
|
result = a
|
|
} else {
|
|
result = b
|
|
}
|
|
}
|
|
return
|
|
}
|