func TestRepeatingDelayOK(tst *testing.T) {
decoupler := NewDecoupler(10, nil, nil)
go decoupler.ProcessLoop(1 * time.Second)
l := latch.NewCountdownLatch(5)
latchShort := latch.NewCountdownLatch(1)
task := func() (executor.ExecutionResult, error) {
l.CountDown()
if !latchShort.Completed() {
latchShort.CountDown()
}
return executor.EX_OK, nil
}
decoupler.ExecuteEvery(1*time.Second, 1*time.Second, 5, task)
// We want this latch to time out.
if !latchShort.AwaitTimeout(1 * time.Second) {
tst.Fatal("Should fail.")
}
// This one should not time out.
if l.AwaitTimeout(12 * time.Second) {
tst.Fatal("Task did not complete", l.Canceled(), l.TimedOut())
}
decoupler.StopProcessLoop(1 * time.Second)
}
func TestErrorCalled(tst *testing.T) {
decoupler := NewDecoupler(10, nil, nil)
go decoupler.ProcessLoop(1 * time.Second)
l := latch.NewCountdownLatch(1)
errorLatch := latch.NewCountdownLatch(1)
decoupler.SetOnError(func(*Decoupler, *executor.TaskCell) executor.ExecutionResult {
errorLatch.CountDown()
return executor.EX_DROP
})
task := func() (executor.ExecutionResult, error) {
l.CountDown()
return executor.EX_FAILED, errors.New("Aardvark application error")
}
decoupler.ExecuteEvery(1*time.Second, 1*time.Second, 5, task)
// We want this latch to time out.
if errorLatch.AwaitTimeout(5 * time.Second) {
tst.Fatal("Error latch failed to fire.")
}
// This one should not time out.
if l.AwaitTimeout(5 * time.Second) {
tst.Fatal("Task did not complete", l.Canceled(), l.TimedOut())
}
decoupler.StopProcessLoop(1 * time.Second)
}
func TestDropCalled(tst *testing.T) {
decoupler := NewDecoupler(1, nil, nil)
go decoupler.ProcessLoop(1 * time.Second)
dropLatch := latch.NewCountdownLatch(2)
decoupler.SetOnDrop(func(*Decoupler, *executor.TaskCell) {
dropLatch.CountDown()
})
task := func() (executor.ExecutionResult, error) {
time.Sleep(2 * time.Second)
return executor.EX_OK, nil
}
time.AfterFunc(2*time.Second, func() {
decoupler.Execute(task) // This may get picked up immediately.
decoupler.Execute(task) // So we need three to ensure while the first is blocking
decoupler.Execute(task) // The remainder attempt to overflow.
})
// We want this latch to time out.
if dropLatch.AwaitTimeout(5 * time.Second) {
tst.Fatal("Error latch failed to fire.")
}
decoupler.StopProcessLoop(1 * time.Second)
}
func (c *CatServiceProviderLocal) AddCat(name string, legs int) {
l := latch.NewCountdownLatch(1)
acr := addCatRequest{name, legs, l, c}
c.dec.Execute(acr.Run)
l.Await() // Use the timeout version if you wish..
}
//
// Set a value on the map.
//
func (r *Register) AddEntry(name string) {
ltch := latch.NewCountdownLatch(1)
task := registerAddTask{r, ltch, name}
r.dec.Execute(task.Run)
ltch.Await()
}
func TestNormalExecute(tst *testing.T) {
decoupler := NewDecoupler(10, nil, nil)
go decoupler.ProcessLoop(1 * time.Second)
l := latch.NewCountdownLatch(1)
task := func() (executor.ExecutionResult, error) {
l.CountDown()
return executor.EX_OK, nil
}
decoupler.ExecuteAfter(2*time.Second, task)
// This one should not time out.
if l.AwaitTimeout(3 * time.Second) {
tst.Fatal("Task did not complete", l.Canceled(), l.TimedOut())
}
decoupler.StopProcessLoop(1 * time.Second)
}
// NewFutureWithListener with an optional listener.
//
func NewFutureWithListener(onValue func(bool, interface{})) *Future {
return &Future{latch.NewCountdownLatch(1), nil, 0, &sync.Mutex{}, &sync.Mutex{}, onValue}
}
// NewFuture creates a new future with no listener.
//
func NewFuture() *Future {
return &Future{latch.NewCountdownLatch(1), nil, 0, &sync.Mutex{}, &sync.Mutex{}, nil}
}
func main() {
sites := []string{"http://www.theage.com.au", "http://www.cisco.com", "http://www.dilbert.com", "www.google.com"}
results := make([]*QueryResult, len(sites))
l := latch.NewCountdownLatch(len(sites))
// A function that fetches the content of a web page and sets a pointer to the content into a result array.
search := func(resultIndex int, query string) {
//
// Note the order of declaration of each defer statement.
//
defer func() {
// If the await has completed(finished an await) then an attempt to count down will fail.
// We can catch this and squash it for the sake of the example.
r := recover()
if r != nil {
if lerr, ok := r.(latch.LatchError); ok {
println(query, lerr.Error())
}
}
}()
//
// Attempt a latch countdown.
//
defer l.CountDown()
resp, err := http.Get(query)
if err != nil {
results[resultIndex] = &QueryResult{Error: err}
return
}
defer resp.Body.Close()
body, err := ioutil.ReadAll(resp.Body)
if err != nil {
results[resultIndex] = &QueryResult{Error: err}
return
}
results[resultIndex] = &QueryResult{query, nil, body}
}
//
// Spin up a new go routine for each query.
//
for t, v := range sites {
go search(t, v)
}
//
// Wait 2 seconds for the requests to complete..
//
if l.AwaitTimeout(2 * time.Second) {
// An issue occurred.
if l.Canceled() {
// It was canceled.
}
if l.TimedOut() {
println("Distributed query timed out..")
}
}
//
// Print the results.
//
for t, v := range results {
if v == nil {
println("Query ", t, "Did not return in time.")
continue
}
println(t, "Query: ", v.Query)
if v.Error != nil {
println(" Error:", v.Error.Error())
} else {
println(" Body Length: ", len(v.Body))
}
}
}
