// getWorkFromSpec forcibly retrieves a work unit from a work spec.
// It could create a work unit if spec is a continuous spec with no
// available units. It ignores other constraints, such as whether the
// work spec is paused.
func (w *worker) getWorkFromSpec(spec *workSpec, meta *coordinate.WorkSpecMeta) *attempt {
var unit *workUnit
now := w.Coordinate().clock.Now()
if len(spec.available) != 0 {
unit = spec.available.Next()
} else if meta.CanStartContinuous(now) {
// Make a brand new work unit. Its key is the string
// form of a time_t.
seconds := now.Unix()
nano := now.Nanosecond()
milli := nano / 1000000
name := fmt.Sprintf("%d.%03d", seconds, milli)
var exists bool
unit, exists = spec.workUnits[name]
if !exists {
unit = &workUnit{
name: name,
data: map[string]interface{}{},
workSpec: spec,
}
spec.workUnits[name] = unit
}
spec.meta.NextContinuous = now.Add(meta.Interval)
} else {
return nil
}
return w.makeAttempt(unit, time.Duration(0))
}
func (w *worker) requestAttemptsForSpec(req coordinate.AttemptRequest, spec *workSpec, meta *coordinate.WorkSpecMeta) ([]coordinate.Attempt, error) {
var (
attempts []coordinate.Attempt
count int
err error
)
// Adjust the work unit count based on what's possible here
count = req.NumberOfWorkUnits
if count < 1 {
count = 1
}
if meta.MaxAttemptsReturned > 0 && count > meta.MaxAttemptsReturned {
count = meta.MaxAttemptsReturned
}
if meta.MaxRunning > 0 && count > meta.MaxRunning-meta.PendingCount {
count = meta.MaxRunning - meta.PendingCount
}
// Now choose units and create attempts
err = withTx(w, func(tx *sql.Tx) error {
units, err := w.chooseWorkUnits(tx, spec, count)
if err != nil {
return err
}
now := w.Coordinate().clock.Now()
if len(units) == 0 && meta.CanStartContinuous(now) {
units, err = w.createContinuousUnits(tx, spec, meta)
}
if err != nil {
return err
}
length := time.Duration(15) * time.Minute
for _, unit := range units {
a, err := makeAttempt(tx, unit, w, length)
if err != nil {
return err
}
attempts = append(attempts, a)
}
return nil
})
return attempts, err
}