| 1 | package async |
| 2 | |
| 3 | import ( |
| 4 | "sync" |
| 5 | "sync/atomic" |
| 6 | "time" |
| 7 | |
| 8 | "go.bigb.es/auxilia/goroutine" |
| 9 | ) |
| 10 | |
| 11 | // TaskInfo holds metadata about a running task for debugging and investigation. |
| 12 | type TaskInfo struct { |
| 13 | ID uint64 |
| 14 | Tags []string |
| 15 | StartTime time.Time |
| 16 | GoroutineID uint64 |
| 17 | done <-chan struct{} |
| 18 | } |
| 19 | |
| 20 | // IsRunning reports whether the task is still running. |
| 21 | func (ti *TaskInfo) IsRunning() bool { |
| 22 | select { |
| 23 | case <-ti.done: |
| 24 | return false |
| 25 | default: |
| 26 | return true |
| 27 | } |
| 28 | } |
| 29 | |
| 30 | // Stacktrace returns the stack trace of the goroutine running this task. |
| 31 | // Returns empty string if the task has already finished. |
| 32 | func (ti *TaskInfo) Stacktrace() string { |
| 33 | if !ti.IsRunning() { |
| 34 | return "" |
| 35 | } |
| 36 | return goroutine.Stack(ti.GoroutineID) |
| 37 | } |
| 38 | |
| 39 | var taskIDSeq atomic.Uint64 |
| 40 | |
| 41 | // Registry stores metadata about all running tasks for investigation. |
| 42 | type Registry struct { |
| 43 | mu sync.RWMutex |
| 44 | tasks map[uint64]*TaskInfo |
| 45 | } |
| 46 | |
| 47 | // NewRegistry creates a new [Registry]. |
| 48 | func NewRegistry() *Registry { |
| 49 | return &Registry{ |
| 50 | tasks: make(map[uint64]*TaskInfo), |
| 51 | } |
| 52 | } |
| 53 | |
| 54 | func (r *Registry) register(done <-chan struct{}, goroutineID uint64, tags []string) uint64 { |
| 55 | id := taskIDSeq.Add(1) |
| 56 | info := &TaskInfo{ |
| 57 | ID: id, |
| 58 | Tags: tags, |
| 59 | StartTime: time.Now(), |
| 60 | GoroutineID: goroutineID, |
| 61 | done: done, |
| 62 | } |
| 63 | |
| 64 | r.mu.Lock() |
| 65 | r.tasks[id] = info |
| 66 | r.mu.Unlock() |
| 67 | |
| 68 | go func() { |
| 69 | <-done |
| 70 | r.mu.Lock() |
| 71 | delete(r.tasks, id) |
| 72 | r.mu.Unlock() |
| 73 | }() |
| 74 | |
| 75 | return id |
| 76 | } |
| 77 | |
| 78 | // Get returns the [TaskInfo] for a task by ID, or nil if not found. |
| 79 | func (r *Registry) Get(id uint64) *TaskInfo { |
| 80 | r.mu.RLock() |
| 81 | defer r.mu.RUnlock() |
| 82 | return r.tasks[id] |
| 83 | } |
| 84 | |
| 85 | // All returns a snapshot of all currently running tasks. |
| 86 | func (r *Registry) All() []*TaskInfo { |
| 87 | r.mu.RLock() |
| 88 | defer r.mu.RUnlock() |
| 89 | |
| 90 | out := make([]*TaskInfo, 0, len(r.tasks)) |
| 91 | for _, info := range r.tasks { |
| 92 | out = append(out, info) |
| 93 | } |
| 94 | return out |
| 95 | } |
| 96 | |
| 97 | // ByTag returns all running tasks that have the given tag. |
| 98 | func (r *Registry) ByTag(tag string) []*TaskInfo { |
| 99 | r.mu.RLock() |
| 100 | defer r.mu.RUnlock() |
| 101 | |
| 102 | var out []*TaskInfo |
| 103 | for _, info := range r.tasks { |
| 104 | for _, t := range info.Tags { |
| 105 | if t == tag { |
| 106 | out = append(out, info) |
| 107 | break |
| 108 | } |
| 109 | } |
| 110 | } |
| 111 | return out |
| 112 | } |
| 113 | |
| 114 | // Len returns the number of currently registered tasks. |
| 115 | func (r *Registry) Len() int { |
| 116 | r.mu.RLock() |
| 117 | defer r.mu.RUnlock() |
| 118 | return len(r.tasks) |
| 119 | } |
| 120 | |
| 121 | |
| 122 | |