woodpecker/cncd/queue/queue.go
2019-06-28 08:29:57 +02:00

138 lines
3.1 KiB
Go

package queue
import (
"context"
"errors"
)
var (
// ErrCancel indicates the task was cancelled.
ErrCancel = errors.New("queue: task cancelled")
// ErrNotFound indicates the task was not found in the queue.
ErrNotFound = errors.New("queue: task not found")
)
// Task defines a unit of work in the queue.
type Task struct {
// ID identifies this task.
ID string `json:"id,omitempty"`
// Data is the actual data in the entry.
Data []byte `json:"data"`
// Labels represents the key-value pairs the entry is lebeled with.
Labels map[string]string `json:"labels,omitempty"`
// Task IDs this task depend
Dependencies []string
// If dep finished sucessfully
DepStatus map[string]bool
// RunOn failure or success
RunOn []string
}
// ShouldRun tells if a task should be run or skipped, based on dependencies
func (t *Task) ShouldRun() bool {
if runsOnFailure(t.RunOn) && runsOnSuccess(t.RunOn) {
return true
}
if !runsOnFailure(t.RunOn) && runsOnSuccess(t.RunOn) {
for _, success := range t.DepStatus {
if !success {
return false
}
}
return true
}
if runsOnFailure(t.RunOn) && !runsOnSuccess(t.RunOn) {
for _, success := range t.DepStatus {
if success {
return false
}
}
return true
}
return false
}
func runsOnFailure(runsOn []string) bool {
for _, status := range runsOn {
if status == "failure" {
return true
}
}
return false
}
func runsOnSuccess(runsOn []string) bool {
if len(runsOn) == 0 {
return true
}
for _, status := range runsOn {
if status == "success" {
return true
}
}
return false
}
// InfoT provides runtime information.
type InfoT struct {
Pending []*Task `json:"pending"`
Running []*Task `json:"running"`
Stats struct {
Workers int `json:"worker_count"`
Pending int `json:"pending_count"`
Running int `json:"running_count"`
Complete int `json:"completed_count"`
} `json:"stats"`
Paused bool
}
// Filter filters tasks in the queue. If the Filter returns false,
// the Task is skipped and not returned to the subscriber.
type Filter func(*Task) bool
// Queue defines a task queue for scheduling tasks among
// a pool of workers.
type Queue interface {
// Push pushes a task to the tail of this queue.
Push(c context.Context, task *Task) error
// Push pushes a task to the tail of this queue.
PushAtOnce(c context.Context, tasks []*Task) error
// Poll retrieves and removes a task head of this queue.
Poll(c context.Context, f Filter) (*Task, error)
// Extend extends the deadline for a task.
Extend(c context.Context, id string) error
// Done signals the task is complete.
Done(c context.Context, id string) error
// Error signals the task is complete with errors.
Error(c context.Context, id string, err error) error
// Evict removes a pending task from the queue.
Evict(c context.Context, id string) error
// Wait waits until the task is complete.
Wait(c context.Context, id string) error
// Info returns internal queue information.
Info(c context.Context) InfoT
// Stops the queue from handing out new work items in Poll
Pause()
// Starts the queue again, Poll returns new items
Resume()
}