Design Cron

• Cron 调度
  • 重复
    • pattern
    • every
  • 是否立即开始
  • timezone
    • timezone id
    • utc offset
• 任务调度
  • 是否并行 - 等待上一个完成

* * * * * *

• 秒
  • 0-59
• 分
  • 0-59
• 时
  • 0-23
• 日
  • 1-31
• 月
  • 1-12
  • JAN-DEC
• 周/星期 - day of week
  • 0-7
  • MIN-SUN
• 年 - 可选

symbol	for
*	all
/	step
,	list
-	range
?	ignore,no specific value
L	last
W	weekday
#	nth

alias	for
@reboot	重启后执行一次, crond
@yearly	0 0 1 1 *
@annually	@yearly
@monthly	0 0 1 * *
@weekly	0 0 * * 0
@daily	0 0 * * *
@midnight	@daily
@hourly	0 * * * *

e.g.	for	cn
6#3	third Friday of the month	每月第三个星期五
30 10 ? * 5L	0:30 AM on the last Thursday of every month	每月最后一个星期五上午10:30
0 0 0 LW * *	last weekday of the month at midnight	每月最后一个工作日午夜

quartz

• Quartz Scheduler
• org.quartz-scheduler:quartz
• 区分 Job 和 Trigger
• quartz-scheduler/quartz
• https://javadoc.io/doc/org.quartz-scheduler/quartz/latest/org/quartz/JobBuilder.html

K8S CronJob

• https://kubernetes.io/docs/concepts/workloads/controllers/cron-jobs/
• https://kubernetes.io/docs/reference/generated/kubernetes-api/v1.32/#cronjob-v1-batch

type CronJobSpec = {
  concurrencyPolicy: string;
  failedJobsHistoryLimit: number; // 保留失败任务的数量
  successfulJobsHistoryLimit: number; // 保留成功任务的数量
  schedule: string; // cron
  startingDeadlineSeconds: number;
  suspend: boolean; // 暂停
  timeZone: string;
  jobTemplate: JobTemplateSpec;
};

type JobTemplateSpec = {
  metadata: ObjectMeta;
  spec: JobSpec;
};
type JobSpec = {
  activeDeadlineSeconds: number; // 超时时间
  backoffLimit: number; // 重试次数
  backoffLimitPerIndex: number; //
  completionMode: string; // 完成模式
  completions: number; // 完成次数
  managedBy: string; // 管理者
  manualSelector: boolean; // 手动选择
  maxFailedIndexes: number; // 最大失败索引
  parallelism: number; // 并行度
  podFailurePolicy: PodFailurePolicy;
  podReplacementPolicy: string; // pod 替换策略
  successPolicy: SuccessPolicy;
  suspend: boolean; // 暂停
  ttlSecondsAfterFinished: number; // 完成后的存活时间
  selector: LabelSelector; // 选择器
  template: PodTemplateSpec; // pod 模板
};

Nomad Perriodic

type Periodic = {
  /**
   * @deprecated
   */
  cron: string;
  crons: string[];
  prohibit_overlap: boolean;
  time_zone: string;
  enabled: boolean;
};

job "docs" {
  periodic {
    cron             = "*/15 * * * * *"
    prohibit_overlap = true
  }
}

• https://developer.hashicorp.com/nomad/docs/job-specification/periodic

node cron

• https://github.com/kelektiv/node-cron

export type CronContext<C> = C extends null ? CronJob : NonNullable<C>;
export type CronCallback<C, WithOnCompleteBool extends boolean = false> = (
  this: CronContext<C>,
  onComplete: WithOnCompleteBool extends true ? CronOnCompleteCallback : never,
) => void | Promise<void>;
export type CronOnCompleteCallback = () => void | Promise<void>;
export type CronSystemCommand =
  | string
  | {
      command: string;
      args?: readonly string[] | null;
      options?: SpawnOptions | null;
    };
export type CronCommand<C, WithOnCompleteBool extends boolean = false> =
  | CronCallback<C, WithOnCompleteBool>
  | CronSystemCommand;

interface BaseCronJobParams<OC extends CronOnCompleteCommand | null = null, C = null> {
  cronTime: string | Date | DateTime;
  onTick: CronCommand<C, WithOnComplete<OC>>;
  onComplete?: OC;
  start?: boolean | null;
  context?: C;
  runOnInit?: boolean | null;
  unrefTimeout?: boolean | null;
  waitForCompletion?: boolean | null;
  errorHandler?: ((error: unknown) => void) | null;
}

export type CronJobParams<OC extends CronOnCompleteCommand | null = null, C = null> = BaseCronJobParams<OC, C> &
  (
    | {
        timeZone?: string | null;
        utcOffset?: never;
      }
    | {
        timeZone?: never;
        utcOffset?: number | null;
      }
  );

BullMQ

• Repeatable
• https://github.com/taskforcesh/bullmq

/**
 * Settings for repeatable jobs
 *
 * @see {@link https://docs.bullmq.io/guide/jobs/repeatable}
 */
export interface RepeatOptions extends Omit<ParserOptions, 'iterator'> {
  /**
   * A repeat pattern
   */
  pattern?: string;

  /**
   * Custom repeatable key. This is the key that holds the "metadata"
   * of a given repeatable job. This key is normally auto-generated but
   * it is sometimes useful to specify a custom key for easier retrieval
   * of repeatable jobs.
   */
  key?: string;

  /**
   * Number of times the job should repeat at max.
   */
  limit?: number;

  /**
   * Repeat after this amount of milliseconds
   * (`pattern` setting cannot be used together with this setting.)
   */
  every?: number;

  /**
   * Repeated job should start right now
   * ( work only with cron settings)
   */
  immediately?: boolean;

  /**
   * The start value for the repeat iteration count.
   */
  count?: number;

  /**
   * Offset in milliseconds to affect the next iteration time
   *
   * */
  offset?: number;

  /**
   * Internal property to store the previous time the job was executed.
   */
  prevMillis?: number;

  /**
   * Internal property to store de job id
   * @deprecated
   */
  jobId?: string;
}