// Produce implements Producer. It creates a new value from the Generator every
// interval, and sends it down the provided channel
func (p *BaseProducer) Produce(kill <-chan struct{}) <-chan []Output {
out := make(chan []Output)
go func() {
defer close(out)
t := util.NewTicker(p.Interval, true)
defer t.Kill()
for {
select {
case <-t.C:
data, err := p.Generate()
if err != nil {
fmt.Fprintf(os.Stderr, "Error generating output for %v: %v\n", p.Name, err)
data = []Output{{
FullText: fmt.Sprintf("ERROR from %v: %v", p.Name, err),
Color: DefaultColors.Crit,
Separator: true,
}}
}
// Attempt to send the output
p.sendOutput(out, data, kill)
case <-kill:
return
}
}
}()
return out
}
func (i *I3bar) loop() {
defer close(i.json)
t := util.NewTicker(i.interval, true)
defer t.Kill()
go output(i.json)
for {
select {
case update := <-i.in:
i.values[update.Key] = update.Out
case event := <-i.clicks:
producer, ok := i.producers[event.Name]
if !ok {
// Somebody didn't register with the right name, oh well
continue
}
clicker, ok := producer.(Clicker)
if !ok {
// Producer doesn't support clicking, oh well
continue
}
go clicker.Click(event)
case <-t.C:
items := i.collect()
select {
case <-i.kill:
return
case i.json <- items:
continue
}
case <-i.kill:
return
}
}
}
// generateIO generates a map of interface name to average disk IO for the
// past interval each interval, and sends it down the channel. Any errors are
// sent down the error channel
func generateIO(kill <-chan struct{}, interval time.Duration,
devices ...string) (<-chan map[string]float64, chan error) {
out := make(chan map[string]float64)
errCh := make(chan error)
go func() {
tick := util.NewTicker(interval, true)
defer tick.Kill()
secs := interval.Seconds()
// Keeps a record of our last checked IO count, so we can calculate our delta
prev := make(map[string]uint64, len(devices))
for {
select {
case <-tick.C:
send := make(map[string]float64, len(devices))
stats, err := currentIOStatus(devices...)
if err != nil {
errCh <- err
continue
}
for _, d := range devices {
// Retrieve the IO stats of this device
usage, ok := stats[d]
if !ok {
errCh <- fmt.Errorf("No device found: %v", d)
continue
}
// Retrieve previous value from cache
pr, ok := prev[d]
if !ok {
// If unavailable send zero, then update cache
prev[d] = usage
send[d] = 0
continue
}
diff := float64(usage - pr)
// Create average throughput by dividing by number of secs in interval
val := diff / secs
if diff == 0 {
val = 0.0
}
// Update map to send
send[d] = val
// Update cache
prev[d] = usage
}
out <- send
case <-kill:
return
}
}
}()
return out, errCh
}