feat: add logic to get jobs

[immanuel192]

Changes

• Add tryLock argument for all the job schedule function. This argument is available in Scheduler but not being use in Schedule service
• Add getJobIds and getJobById. Just in case that we need to manually control the job.
• Update the readme
• For the cron job, safely use start time and end time
• Allow pass arguments when invoke a job. This will be useful when you want to manually trigger a job

[immanuel192]

@miaowing can u please help review this change. If possible I would like to have it asap for my project :) instead of using hacky way. thanks

[miaowing]

Thank your for your pull request.
Dynamic job is not support distribution now, because the job is not sync to other nodes in cluster, tryLock function in this has no effect. Maybe I will resolve it in the future.

[immanuel192]

I think it still ok for some cases. In my project, user can upload csv files. My app (which is running in multiple instances) will try to pick up the csv file to process data. In this case, I have to make sure that the mutex lock is good enough to not let other instances pick up the same file.

[meredian]

@miaowing Hi! Found that PR. I was looking for similar thing - personally I'm interested in "show info when next run happens" and considered exposing job.nextInvocation() from node-schedule.

I see PR is a little bit stale. So maybe I could rework bits of this to make it happen. How'd you think?