Configuration

Queue capacity, worker count, timeouts, and named presets.

Config

Pass a *Config to New. A nil config uses all defaults.

type Config struct {
    Workers int                     // default = CPU * 2
    Size    int                     // default = Workers * 64
    Timeout time.Duration           // default = 30 * seconds
    Preset  map[string]PresetConfig // default = empty
}

Field	Type	Default	Description
`Workers`	`int`	`runtime.NumCPU() * 2`	Number of worker goroutines
`Size`	`int`	`Workers * 64`	Maximum pending heap capacity
`Timeout`	`time.Duration`	`30 * time.Second`	Base timeout used for derivation and promotion
`Preset`	`map[string]PresetConfig`	empty map	Named priority and timeout presets

Zero values for Workers, Size, and Timeout fall back to defaults. A non-nil Preset map is deep-copied into the queue config.

PresetConfig

type PresetConfig struct {
    Priority Priority
    Timeout  time.Duration
}

Field	Description
`Priority`	Task priority when this preset name is used in `Enqueue`
`Timeout`	When `> 0`, overrides base `Config.Timeout` before priority scaling; when `0`, uses base timeout

Example

q := goQueue.New(&goQueue.Config{
    Workers: 4,
    Size:    256,
    Timeout: 30 * time.Second,
    Preset: map[string]goQueue.PresetConfig{
        "urgent": {Priority: goQueue.PriorityImmediate},
        "batch":  {Priority: goQueue.PriorityLow, Timeout: 60 * time.Second},
    },
})

Timeout Derivation

Resolved timeout for each enqueue (before WithTimeout override):

Start from Config.Timeout.
If the preset name exists and PresetConfig.Timeout > 0, use that value instead.
Scale by the preset's Priority.
Clamp to 15s–120s.

Priority	Formula
Immediate	`timeout / 4`
High	`timeout / 2`
Retry	`timeout / 2`
Normal	`timeout`
Low	`timeout * 2`

WithTimeout(d) replaces the derived value entirely for that enqueue.

Priority Promotion Thresholds

Promotion wait times are derived once at New from Config.Timeout:

From	Wait	To
Low	`clamp(Timeout, 30s, 120s)`	Normal
Normal	`clamp(Timeout*2, 30s, 120s)`	High

Changing Timeout after New has no effect — the promotion map is fixed at construction.

Enqueue Options

Per-task overrides applied at enqueue time:

Option	Effect
`WithTaskID(id)`	Sets task ID; empty/omitted → auto UUID
`WithTimeout(d)`	Overrides derived timeout
`WithCallback(fn)`	Runs `fn(id)` in a new goroutine after success
`WithRetry(max...)`	Enables retry; optional max (default 3)

Defaults Summary

Setting	Default
Workers	`runtime.NumCPU() * 2`
Size	`Workers * 64`
Timeout	`30s`
Min derived timeout	`15s`
Max derived timeout	`120s`
Retry max (when enabled, no arg)	`3`
Empty preset name priority	`PriorityImmediate` (zero value of unset map entry)