vendor/github.com/apigee-labs/transicator/changeserver/changetracker_test.go

/*
Copyright 2016 The Transicator 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 main

import (
	"fmt"
	"math/rand"
	"sync/atomic"
	"time"

	"github.com/apigee-labs/transicator/common"
	. "github.com/onsi/ginkgo"
	. "github.com/onsi/gomega"
)

const (
	startIndex         = 2
	maxWait            = 10 * time.Microsecond
	trackerTestTimeout = 10 * time.Second
	trackerCount       = 1000
)

var tracker *changeTracker

var _ = Describe("Change tracker", func() {
	BeforeEach(func() {
		tracker = createTracker()
		tracker.update(common.MakeSequence(uint64(startIndex), 0), "")
	})

	AfterEach(func() {
		tracker.close()
	})

	It("Behind", func() {
		behind := tracker.wait(common.MakeSequence(1, 0), []string{""})
		Expect(behind.LSN).Should(BeEquivalentTo(2))
	})

	It("Behind with selectors", func() {
		tracker.update(common.MakeSequence(3, 0), "foo")
		tracker.update(common.MakeSequence(4, 0), "bar")
		behind := tracker.wait(common.MakeSequence(1, 0), []string{"foo"})
		Expect(behind.LSN).Should(BeEquivalentTo(3))
		behind = tracker.wait(common.MakeSequence(1, 0), []string{"bar"})
		Expect(behind.LSN).Should(BeEquivalentTo(4))
		behind = tracker.wait(common.MakeSequence(1, 0), []string{"foo", "bar"})
		Expect(behind.LSN).Should(BeEquivalentTo(4))
		behind = tracker.wait(common.MakeSequence(1, 0), []string{"bar", "foo"})
		Expect(behind.LSN).Should(BeEquivalentTo(4))
	})

	It("Caught up", func() {
		behind := tracker.wait(common.MakeSequence(2, 0), []string{""})
		Expect(behind.LSN).Should(BeEquivalentTo(2))
	})

	It("Caught up with selectors", func() {
		tracker.update(common.MakeSequence(3, 0), "foo")
		tracker.update(common.MakeSequence(4, 0), "bar")
		time.Sleep(time.Millisecond * 250)

		behind := tracker.wait(common.MakeSequence(2, 0), []string{"foo"})
		Expect(behind.LSN).Should(BeEquivalentTo(3))
		behind = tracker.wait(common.MakeSequence(2, 0), []string{"bar"})
		Expect(behind.LSN).Should(BeEquivalentTo(4))
		behind = tracker.wait(common.MakeSequence(2, 0), []string{"foo", "bar"})
		Expect(behind.LSN).Should(BeEquivalentTo(4))
	})

	It("Timeout", func() {
		blocked := tracker.timedWait(common.MakeSequence(3, 0), 250*time.Millisecond, []string{""})
		Expect(blocked.LSN).Should(BeEquivalentTo(0))
	})

	It("Up to date", func() {
		doneChan := make(chan uint64, 1)

		go func() {
			new := tracker.wait(common.MakeSequence(3, 0), []string{""})
			doneChan <- new.LSN
		}()

		tracker.update(common.MakeSequence(3, 0), "")
		Eventually(doneChan).Should(Receive(BeEquivalentTo(3)))
	})

	It("Up to date with timeout", func() {
		doneChan := make(chan uint64, 1)

		go func() {
			new := tracker.timedWait(common.MakeSequence(3, 0), 2*time.Second, []string{""})
			doneChan <- new.LSN
		}()

		tracker.update(common.MakeSequence(3, 0), "")
		Eventually(doneChan).Should(Receive(BeEquivalentTo(3)))
	})

	It("Behind with tags", func() {
		doneChanFoo := make(chan uint64, 1)
		doneChanBar := make(chan uint64, 1)

		go func() {
			new := tracker.wait(common.MakeSequence(4, 0), []string{"foo"})
			doneChanFoo <- new.LSN
		}()

		go func() {
			new := tracker.timedWait(common.MakeSequence(4, 0), 2*time.Second, []string{"bar"})
			doneChanBar <- new.LSN
		}()

		time.Sleep(250 * time.Millisecond)
		tracker.update(common.MakeSequence(4, 0), "foo")

		Eventually(doneChanFoo).Should(Receive(BeEquivalentTo(4)))
		Eventually(doneChanBar, 5*time.Second).Should(Receive(BeZero()))
	})

	It("Tag never updated", func() {
		blocked := tracker.timedWait(common.MakeSequence(3, 0), 250*time.Millisecond, []string{"baz"})
		Expect(blocked.LSN).Should(BeEquivalentTo(0))
	})

	It("Less up to date with timeout", func() {
		doneChan := make(chan uint64, 1)

		go func() {
			new := tracker.timedWait(common.MakeSequence(4, 0), 2*time.Second, []string{""})
			doneChan <- new.LSN
		}()

		tracker.update(common.MakeSequence(3, 0), "")
		tracker.update(common.MakeSequence(4, 0), "")
		Eventually(doneChan).Should(Receive(BeEquivalentTo(4)))
	})

	It("Up to date timeout", func() {
		doneChan := make(chan uint64, 1)

		go func() {
			new := tracker.timedWait(common.MakeSequence(3, 0), 250*time.Millisecond, []string{""})
			doneChan <- new.LSN
		}()

		time.Sleep(1 * time.Second)
		tracker.update(common.MakeSequence(3, 0), "")
		Eventually(doneChan).Should(Receive(BeEquivalentTo(0)))
	})

	It("Update", func() {
		doneChan := make(chan uint64, 1)

		go func() {
			new := tracker.wait(common.MakeSequence(4, 0), []string{""})
			doneChan <- new.LSN
		}()

		time.Sleep(250 * time.Millisecond)
		tracker.update(common.MakeSequence(3, 0), "")
		time.Sleep(250 * time.Millisecond)
		tracker.update(common.MakeSequence(4, 0), "")
		Eventually(doneChan).Should(Receive(BeEquivalentTo(4)))
	})

	It("Update with selectors", func() {
		doneChan := make(chan uint64, 1)

		go func() {
			new := tracker.wait(common.MakeSequence(4, 0), []string{"baz"})
			doneChan <- new.LSN
		}()

		time.Sleep(250 * time.Millisecond)
		tracker.update(common.MakeSequence(3, 0), "baz")
		time.Sleep(250 * time.Millisecond)
		tracker.update(common.MakeSequence(4, 0), "baz")
		Eventually(doneChan).Should(Receive(BeEquivalentTo(4)))
	})

	It("Update with two selectors", func() {
		doneChan := make(chan uint64, 1)

		go func() {
			new := tracker.wait(common.MakeSequence(4, 0), []string{"bar", "baz"})
			doneChan <- new.LSN
		}()

		time.Sleep(250 * time.Millisecond)
		tracker.update(common.MakeSequence(3, 0), "foo")
		time.Sleep(250 * time.Millisecond)
		tracker.update(common.MakeSequence(4, 0), "baz")
		Eventually(doneChan).Should(Receive(BeEquivalentTo(4)))
	})

	It("Update twice", func() {
		doneChan := make(chan uint64, 1)
		doneChan2 := make(chan uint64, 1)

		go func() {
			new := tracker.wait(common.MakeSequence(4, 0), []string{""})
			doneChan <- new.LSN
		}()

		go func() {
			new2 := tracker.wait(common.MakeSequence(4, 0), []string{""})
			doneChan2 <- new2.LSN
		}()

		time.Sleep(250 * time.Millisecond)
		tracker.update(common.MakeSequence(3, 0), "")
		time.Sleep(250 * time.Millisecond)
		tracker.update(common.MakeSequence(4, 0), "")
		got := <-doneChan
		Expect(got).Should(BeEquivalentTo(4))
		got = <-doneChan2
		Expect(got).Should(BeEquivalentTo(4))
	})

	It("Multi Update", func() {
		prematureDoneChan := make(chan uint64, 1)
		doneChan := make(chan uint64, 1)

		go func() {
			oldNew := tracker.wait(common.MakeSequence(10, 0), []string{""})
			prematureDoneChan <- oldNew.LSN
		}()

		go func() {
			new := tracker.wait(common.MakeSequence(4, 0), []string{""})
			doneChan <- new.LSN
		}()

		time.Sleep(250 * time.Millisecond)
		tracker.update(common.MakeSequence(3, 0), "")
		time.Sleep(250 * time.Millisecond)
		tracker.update(common.MakeSequence(4, 0), "")

		// No loop -- we expect that the first case arrive before the second
		select {
		case gotVal := <-doneChan:
			Expect(gotVal).Should(BeEquivalentTo(4))
		case <-prematureDoneChan:
			Expect(true).Should(BeFalse())
		}
	})

	It("Close", func() {
		tracker = createTracker()
		tracker.update(common.MakeSequence(2, 0), "")
		done := make(chan uint64, 1)

		go func() {
			new := tracker.wait(common.MakeSequence(3, 0), []string{""})
			done <- new.LSN
		}()

		time.Sleep(250 * time.Millisecond)
		tracker.close()

		Eventually(done).Should(Receive(BeEquivalentTo(2)))
	})

	It("Stress 1, 1", func() {
		trackerStress(1, 1, trackerCount)
	})

	It("Stress 100, 1", func() {
		trackerStress(100, 1, trackerCount)
	})

	It("Stress 1, 100", func() {
		trackerStress(1, 100, trackerCount)
	})

	It("Stress 100, 100", func() {
		trackerStress(100, 100, trackerCount)
	})

	It("Stress 100, 1000", func() {
		trackerStress(100, 1000, trackerCount)
	})
})

func trackerStress(producers, consumers int, max int64) {
	// Make a separate tracker here. The global pointer may get shared
	// by multiple tests otherwise as one shuts down while the next starts.
	stressTracker := createTracker()
	defer stressTracker.close()

	var start int64 = startIndex

	prodDone := make(chan bool, producers)
	consDone := make(chan bool, consumers)
	allDone := make(chan bool, 1)

	go func() {
		ticker := time.NewTicker(time.Second)
		count := 0
		for {
			select {
			case <-ticker.C:
				fmt.Fprintf(GinkgoWriter, "%d: %d\n", count, atomic.LoadInt64(&start))
				count++
			case <-allDone:
				return
			}
		}
	}()

	for i := 0; i <= producers; i++ {
		go func() {
			for atomic.LoadInt64(&start) < max {
				waitTime := rand.Int63n(int64(maxWait))
				time.Sleep(time.Duration(waitTime))
				val := atomic.AddInt64(&start, 1)
				seq := common.MakeSequence(uint64(val), 0)
				stressTracker.update(seq, "")
			}
			prodDone <- true
		}()
	}

	for i := 0; i <= consumers; i++ {
		go func() {
			var last int64 = startIndex
			for last < max {
				waitTime := rand.Int63n(int64(maxWait))
				seq := common.MakeSequence(uint64(last+1), 0)
				lastSeq := stressTracker.timedWait(seq, time.Duration(waitTime), []string{""})
				last = int64(lastSeq.LSN)
			}
			consDone <- true
		}()
	}

	prodCount := 0
	consCount := 0

	timeout := time.NewTimer(trackerTestTimeout)
	for prodCount < producers || consCount < consumers {
		select {
		case <-prodDone:
			prodCount++
		case <-consDone:
			consCount++
		case <-timeout.C:
			fmt.Fprintf(GinkgoWriter,
				"Test timed out after %d producers and %d consumers. last = %d\n",
				prodCount, consCount, atomic.LoadInt64(&start))
			//stacks := make([]byte, 1000000)
			//stackLen := runtime.Stack(stacks, true)
			//fmt.Fprintf(GinkgoWriter, string(stacks[:stackLen]))
			Expect(false).Should(BeTrue())
			allDone <- true
			return
		}
	}
	allDone <- true
}