prometheus/retrieval/scheduler_test.go
Matt T. Proud efe61c18fa Refactor target scheduling to separate facility.
``Target`` will be refactored down the road to support various
nuanced endpoint types.  Thusly incorporating the scheduling
behavior within it will be problematic.  To that end, the scheduling
behavior has been moved into a separate assistance type to improve
conciseness and testability.

``make format`` was also run.
2013-01-13 10:43:37 +01:00

112 lines
4.3 KiB
Go

// Copyright 2013 Prometheus Team
// 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 retrieval
import (
"testing"
"time"
)
type fakeHealthReporter struct {
index int
stateQueue []TargetState
}
func (h fakeHealthReporter) State() (state TargetState) {
state = h.stateQueue[h.index]
h.index++
return
}
type fakeTimeProvider struct {
index int
timeQueue []time.Time
}
func (t *fakeTimeProvider) Now() (time time.Time) {
time = t.timeQueue[t.index]
t.index++
return
}
func TestHealthScheduler(t *testing.T) {
now := time.Now()
var scenarios = []struct {
futureHealthState []TargetState
preloadedTimes []time.Time
expectedSchedule []time.Time
}{
// The behavior discussed in healthScheduler.Reschedule should be read
// fully to understand the whys and wherefores.
{
futureHealthState: []TargetState{UNKNOWN, ALIVE, ALIVE},
preloadedTimes: []time.Time{now, now.Add(time.Minute), now.Add(time.Minute * 2)},
expectedSchedule: []time.Time{now, now.Add(time.Minute), now.Add(time.Minute * 2)},
},
{
futureHealthState: []TargetState{UNKNOWN, UNREACHABLE, UNREACHABLE},
preloadedTimes: []time.Time{now, now.Add(time.Minute), now.Add(time.Minute * 2)},
expectedSchedule: []time.Time{now, now.Add(time.Second * 2), now.Add(time.Minute).Add(time.Second * 4)},
},
{
futureHealthState: []TargetState{UNKNOWN, UNREACHABLE, ALIVE},
preloadedTimes: []time.Time{now, now.Add(time.Minute), now.Add(time.Minute * 2)},
expectedSchedule: []time.Time{now, now.Add(time.Second * 2), now.Add(time.Minute * 2)},
},
{
futureHealthState: []TargetState{UNKNOWN, UNREACHABLE, UNREACHABLE, UNREACHABLE, UNREACHABLE, UNREACHABLE, UNREACHABLE, UNREACHABLE, UNREACHABLE, UNREACHABLE, UNREACHABLE, UNREACHABLE, UNREACHABLE},
preloadedTimes: []time.Time{now, now.Add(time.Minute), now.Add(time.Minute * 2), now.Add(time.Minute * 3), now.Add(time.Minute * 4), now.Add(time.Minute * 5), now.Add(time.Minute * 6), now.Add(time.Minute * 7), now.Add(time.Minute * 8), now.Add(time.Minute * 9), now.Add(time.Minute * 10), now.Add(time.Minute * 11), now.Add(time.Minute * 12)},
expectedSchedule: []time.Time{now, now.Add(time.Second * 2), now.Add(time.Minute * 1).Add(time.Second * 4), now.Add(time.Minute * 2).Add(time.Second * 8), now.Add(time.Minute * 3).Add(time.Second * 16), now.Add(time.Minute * 4).Add(time.Second * 32), now.Add(time.Minute * 5).Add(time.Second * 64), now.Add(time.Minute * 6).Add(time.Second * 128), now.Add(time.Minute * 7).Add(time.Second * 256), now.Add(time.Minute * 8).Add(time.Second * 512), now.Add(time.Minute * 9).Add(time.Second * 1024), now.Add(time.Minute * 10).Add(time.Minute * 30), now.Add(time.Minute * 11).Add(time.Minute * 30)},
},
}
for i, scenario := range scenarios {
provider := &fakeTimeProvider{}
for _, time := range scenario.preloadedTimes {
provider.timeQueue = append(provider.timeQueue, time)
}
reporter := fakeHealthReporter{}
for _, state := range scenario.futureHealthState {
reporter.stateQueue = append(reporter.stateQueue, state)
}
if len(scenario.preloadedTimes) != len(scenario.futureHealthState) || len(scenario.futureHealthState) != len(scenario.expectedSchedule) {
t.Fatalf("%d. times and health reports and next time lengths were not equal.", i)
}
timer := timer{
provider: provider,
}
scheduler := healthScheduler{
timer: timer,
target: reporter,
scheduledFor: now,
}
for j := 0; j < len(scenario.preloadedTimes); j++ {
futureState := scenario.futureHealthState[j]
scheduler.Reschedule(scenario.preloadedTimes[j], futureState)
nextSchedule := scheduler.ScheduledFor()
if nextSchedule != scenario.expectedSchedule[j] {
t.Errorf("%d.%d. Expected to be scheduled to %s, got %s", i, j, scenario.expectedSchedule[j], nextSchedule)
}
}
}
}