|
| 1 | +package queue |
| 2 | + |
| 3 | +import ( |
| 4 | + "encoding/json" |
| 5 | + "fmt" |
| 6 | + "sync" |
| 7 | + "time" |
| 8 | + |
| 9 | + "github.com/sheenazien8/goplate/db" |
| 10 | + "github.com/sheenazien8/goplate/pkg/models" |
| 11 | +) |
| 12 | + |
| 13 | +// Task defines the work to be processed by the queue |
| 14 | +type Task func() |
| 15 | + |
| 16 | +// Queue represents a simple in-memory task queue with worker pool |
| 17 | +type Queue struct { |
| 18 | + tasks chan Task |
| 19 | + wg sync.WaitGroup |
| 20 | +} |
| 21 | + |
| 22 | +// New creates a new Queue with the specified buffer size |
| 23 | +func New(bufferSize int) *Queue { |
| 24 | + return &Queue{ |
| 25 | + tasks: make(chan Task, bufferSize), |
| 26 | + } |
| 27 | +} |
| 28 | + |
| 29 | +func (q *Queue) Start(workerCount int) { |
| 30 | + for i := 0; i < workerCount; i++ { |
| 31 | + go func() { |
| 32 | + for { |
| 33 | + var jobRecord models.Job |
| 34 | + err := db.Connect. |
| 35 | + Where("state = ? AND available_at <= ?", models.JobPending, time.Now()). |
| 36 | + Order("created_at ASC"). |
| 37 | + First(&jobRecord).Error |
| 38 | + |
| 39 | + if err != nil { |
| 40 | + time.Sleep(1 * time.Second) |
| 41 | + continue |
| 42 | + } |
| 43 | + |
| 44 | + job, err := ResolveJob(jobRecord.Type, jobRecord.Payload) |
| 45 | + if err != nil { |
| 46 | + failJob(&jobRecord, err) |
| 47 | + continue |
| 48 | + } |
| 49 | + |
| 50 | + start := time.Now() |
| 51 | + db.Connect.Model(&jobRecord).Updates(models.Job{ |
| 52 | + State: models.JobStarted, |
| 53 | + StartedAt: &start, |
| 54 | + }) |
| 55 | + |
| 56 | + err = job.Handle(jobRecord.Payload) |
| 57 | + |
| 58 | + if err != nil { |
| 59 | + jobRecord.Attempts++ |
| 60 | + if jobRecord.Attempts >= job.MaxAttempts() { |
| 61 | + failJob(&jobRecord, err) |
| 62 | + } else { |
| 63 | + db.Connect.Model(&jobRecord).Updates(models.Job{ |
| 64 | + State: models.JobPending, |
| 65 | + ErrorMsg: err.Error(), |
| 66 | + Attempts: jobRecord.Attempts, |
| 67 | + AvailableAt: time.Now().Add(job.RetryAfter()), |
| 68 | + }) |
| 69 | + } |
| 70 | + } else { |
| 71 | + db.Connect.Model(&jobRecord).Updates(models.Job{ |
| 72 | + State: models.JobFinished, |
| 73 | + FinishedAt: ptr(time.Now()), |
| 74 | + }) |
| 75 | + } |
| 76 | + } |
| 77 | + }() |
| 78 | + } |
| 79 | +} |
| 80 | + |
| 81 | +func failJob(job *models.Job, err error) { |
| 82 | + db.Connect.Model(job).Updates(models.Job{ |
| 83 | + State: models.JobFailed, |
| 84 | + ErrorMsg: err.Error(), |
| 85 | + FinishedAt: ptr(time.Now()), |
| 86 | + }) |
| 87 | +} |
| 88 | + |
| 89 | +func ptr[T any](v T) *T { |
| 90 | + return &v |
| 91 | +} |
| 92 | + |
| 93 | +// Registry maps job type string to a function that builds and returns a Job |
| 94 | +var registry = map[string]func() Job{} |
| 95 | + |
| 96 | +// RegisterJob registers a job handler with a type string |
| 97 | +func RegisterJob(job Job) { |
| 98 | + registry[job.Type()] = func() Job { |
| 99 | + return job |
| 100 | + } |
| 101 | +} |
| 102 | + |
| 103 | +// ResolveJob looks up and creates a job instance from type |
| 104 | +func ResolveJob(typeName string, payload json.RawMessage) (Job, error) { |
| 105 | + creator, exists := registry[typeName] |
| 106 | + if !exists { |
| 107 | + return nil, fmt.Errorf("job type '%s' not registered", typeName) |
| 108 | + } |
| 109 | + |
| 110 | + job := creator() |
| 111 | + |
| 112 | + // // optional: decode payload into the job struct if needed |
| 113 | + // if err := json.Unmarshal(payload, &job); err != nil { |
| 114 | + // return nil, fmt.Errorf("failed to unmarshal payload for '%s': %w", typeName, err) |
| 115 | + // } |
| 116 | + |
| 117 | + return job, nil |
| 118 | +} |
| 119 | + |
| 120 | +type JobEnqueueRequest struct { |
| 121 | + Type string |
| 122 | + Payload any |
| 123 | +} |
| 124 | + |
| 125 | +type Job interface { |
| 126 | + Type() string |
| 127 | + Handle(payload json.RawMessage) error |
| 128 | + MaxAttempts() int |
| 129 | + RetryAfter() time.Duration |
| 130 | +} |
| 131 | + |
| 132 | +func Dispatch(job Job, params ...any) error { |
| 133 | + _, err := SaveJobToDB(JobEnqueueRequest{ |
| 134 | + Type: job.Type(), |
| 135 | + Payload: params, |
| 136 | + }) |
| 137 | + if err != nil { |
| 138 | + return fmt.Errorf("failed to save job to DB: %w", err) |
| 139 | + } |
| 140 | + |
| 141 | + return nil |
| 142 | +} |
| 143 | + |
| 144 | +func SaveJobToDB(req JobEnqueueRequest) (*models.Job, error) { |
| 145 | + payloadJSON, err := json.Marshal(req.Payload) |
| 146 | + if err != nil { |
| 147 | + return nil, err |
| 148 | + } |
| 149 | + |
| 150 | + now := time.Now() |
| 151 | + |
| 152 | + job := models.Job{ |
| 153 | + Type: req.Type, |
| 154 | + Payload: payloadJSON, |
| 155 | + State: models.JobPending, |
| 156 | + Attempts: 0, |
| 157 | + AvailableAt: now, |
| 158 | + CreatedAt: now, |
| 159 | + } |
| 160 | + |
| 161 | + if err := db.Connect.Create(&job).Error; err != nil { |
| 162 | + return nil, err |
| 163 | + } |
| 164 | + return &job, nil |
| 165 | +} |
0 commit comments