I'm currently in the process of building an app in MeteorJS that allows users to create jobs and schedule them, e.g. Posting a link to social media every 2 hours. Are there any Meteor or Node packages that would make this possible? I've looked into https://github.com/percolatestudio/meteor-synced-cron, but I'm not sure that this would be the right approach for user submitted jobs (seems to be for jobs you create on app start-up). The idea would be that users could create these jobs and delete them later.
Thanks!
I've used https://github.com/percolatestudio/meteor-synced-cron in an app to check if invoices are due and then fire up email reminders. The jobs run on startup but if you set it to go through the collection of jobs, check the time they were created, and then fire something 2 hours after the creation, I'm sure you'll be able to get the work you need done
You can use a setInterval(); to loop every so often, maybe query a database or something for entries that are over 2 hours old, then act on them.
Related
I have been looking for a time based persistent scheduler. I looked into some applications (Agenda, node-cron, node-schedule). But I couldn't find anything that satisfies my criteria.
So my applications sends out reminders to our customers based on their event timings. I am hesitating to run a regular cronjob because I have to run every 15 mins or so in this case. And for each cronjob, I have to make a database call. I am trying not to use resources unnecessarily.
In addition to that, I am already running a lot of cronjobs. But in my case, when the job is completed, I want the cron to get cancelled/finished; not live on memory until the server restart happens.
I tried using the above specified applications by setting exact timestamps (agenda, node-cron, node-schedule). But the cron lives on forever even after the job is completed, and if i restart the server, all the scheduled jobs are cron. So persistence is also an issue I am facing.
My server uses node js. If there are any other languages/tools to make this work, I am all ears.
Looking forward to your help.
I tried following this solution. But this solution is for one predefined event. In my case, the number of reminders to be sent out are dynamic and jobs are to be scheduled on the fly.
I have a web application, where users can schedule different jobs.
I'am not sure how to proceed with this.
All the nodejs schedulers out there basically reads the schedule from within the code. I can of course implement this cron like schedule to be read from a database, but I'am not sure if its the most effective way?
If I back the solution with a database I would need to query that database, let say each second, to see if there is any schduled jobs that needs to be handled. I can't read them once a day, because new jobs might be added on a regular basis.
Keeping them in memory dosen't seem very efficient either?
Am I looking for a different kind of technology to handle this, than a scheduler+database?
We are talkning around 10.000 jobs for the time being (as a maximum). They are mostly related to sending emails and/or giving notifications within the application itself.
In Kentico (9) when I run the task "Delete inactive contacts" it never actually runs and the result is always "Rescheduled to delete more contacts in next off-peak period"
I've tried changing the settings to run once a week and I've tried creating a custom IDeleteContacts then setting it to use that custom class, but I always get the same result.
Any ideas?
By default, Kentico runs it's scheduled tasks in the tail of regular web requests. That's fine if you have traffic 24/7. If you don't, then you can run into all kinds of nastyness including the issue you're describing now because scheduled tasks are not executing.
If you're running on a Windows server you can setup a service to trigger scheduled tasks. If that's not an option, you can setup monitoring to hit your site every couple of minutes, for example UptimeRobot or Application Insights. You'll get the added bonus of being notified whenever the site goes down.
If you really need to clean up the EMS contacts because it's getting out of control, you can access the database directly and trigger the same stored procedure that the scheduled task uses. It's called [Proc_OM_Contact_MassDelete] and takes a where clause and a batch size. The where clause is where you specify the delete policy. For example
ContactCreated < GETDATE()-60 AND ([ContactEmail] IS NULL PR [ContactEmail]='')
With this where clause the stored proc would process contacts that were created over 60 days ago and don't have an e-mail address yet.
Please be aware that large volumes of EMS data will require database index tuning for this procedure to run within an acceptable period of time. This is true for EMS in general when your site has a decent amount of traffic.
If the standard Kentico cleanup doesn't work, for example because the database is unable to deal with millions of contacts, we've written a script to purge all EMS data. Use with caution ;)
do you have applied the latest hotfix (9.0.50) on your project? There was a bug when the deletion of inactive contacts took longer than 1 minute, the next run of the "Delete inactive contacts" scheduled task was not set, and the task did not execute again. You can download the package directly from this page: https://devnet.kentico.com/download/hotfixes
The "Delete inactive contacts" scheduled task only runs between 2am and 6am based on the servers time the site is running on. You can see this in the documentation. It only ever deletes a batch of 1000 contacts and never more. If you want to "trick" the site into running the scheduled task more, update the time on the server to 1:58am and restart the site.
I'm creating a project in Node & Express that allows users to schedule the server to run test scripts e.g. once every ten minutes. I looked into node-schedule which looks great however it seems that all scheduled tasks disappear if the server ever restarts Node.
Cron looks good too but it has the problem that it doesn't seem to have a way to delete scheduled tasks after they have been set up.
If you were doing this, how would you go about it? I really don't want anything that's going to be complex, just need to schedule tasks, be able to delete individual tasks, and keep tasks in the event of a server reboot.
Simplest solution is to store the configurations for Cron in a database (since it takes a string as a parameter). Load the jobs from the db every time the app starts.
I am developing an application using Azure Cloud Service and web api. I would like to allow users that create a consultation session the ability to change the price of that session, however I would like to allow all users 30 days to leave the session before the new price affects the price for all members currently signed up for the session. My first thought is to use queue storage and set the visibility timeout for the 30 day time limit, but this seems like this could grow the queue really fast over time, especially if the message should not run for 30 days; not to mention the ordering issues. I am looking at the task scheduler as well but the session pricing changes are not a recurring concept but more random. Is the queue idea a good approach or is there a better and more efficient way to accomplish this?
The stuff you are trying to do should be done with a relational database. You can use timestamps to record when prices for session changed. I wouldn't use a queue at all for this. A queue is more for passing messages in a distributed system. Your problem is just about tracking what prices changed on what sessions and when. That data should be modeled in a database.
I think this scenario is more suitable to use Azure Scheduler. Programatically create a Job with one time recurrence with set date as 30 days later to run once. Once this job gets triggered automatically by scheduler, assign an action to callback to one of your API/Service to do the price & other required updates and also remove this Job from the scheduler as part of this action to have a clean jobs list. Anyways premium plan of Azure Scheduler Job Collection will give you unlimited number of jobs to run.
Hope this is exactly what you were looking for...
I would consider using Azure WebJobs. A WebJob basically gives you the ability to run a .NET console application within the context of an Azure Web App. It can be run on demand, continuously, or in response to a reoccurring schedule. If your processing requirements are low and allow for it they can also run in the same process that your Web App is running in to save you $$$ as they are free that way.
You could schedule the WebJob to run once or twice per day and examine the situation and react as is appropriate. Since it's really just a .NET worker role you have ultimate flexibility.