Guide to migrate from delayed_job to resque? - ruby-on-rails

Does anyone have or know of a guide for how to migrate from Delayed Job to Resque? I can't find any on Google and figure I must not be the first one doing this. Just a general list of changes that need to made and things to watch out for would be great.

I have just found this guide.

There is no guide that I could find, but the missing piece of the puzzle is Resque scheduler. Once you get all the Resque stuff running on your server, the actual Rails code changes are incredibly simple. So if you happen to be doing this look for Resque Scheduler and then have at it.

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Rails Background Process (Heroku Rails 3+)

I'm am going to set up some functionality for my app that is Rails 3.2.3 and on Heroku. The idea is to have a task, or job (or whatever you want to call it) run every day, to make sure user information from the external API is up to date with the user information in my db. I'm curious what is the the best way to set this up? Should it be a cron job that runs a rake task?
Seems like there are quite a few ways to do this and I'm interested in the ways others are doing this. The only way I can think to do it is to run a rake task in a cron job, but would love to figure out what best practices are, or the most simple way to do it. Seems like there are a lot of ways to skin this cat... lots of different tools out there too.
If there was a pure rails way to do this, I think that would be better so I don't have to screw around with every system I place my app onto.
For a simple sync job that runs once a day, I believe having a cronjob would be sufficient and likely more stable in the long run.
Honestly, solutions such as Resque and Sidekiq is a bit overkill in my opinion (for your needs). You're still required to use a scheduler to send messages to these systems.
Check out the gem 'whenever' if you're looking at making the deployment and writing of crontabs easier: https://github.com/javan/whenever/
Railscasts regarding 'whenever': http://railscasts.com/episodes/164-cron-in-ruby
There are two options. They're better than options you mentioned in your question
Resque.
Sidekiq.
Try the later one. It is faster, lightweight and based on multithreading so there isn't interference with system. You'll need to look into scheduler of both the gem for processing everyday.
Hope this helps!
Use the Heroku scheduler add on to the handle scheduling itself. You can have it run a rake task, resque, or whatever.
Here is a few to choose from :
resque (with resque-scheduler. But you have to use redis with it)
rufus-scheduler ( if you want something simple, resque uses rufus-scheduler itself)
You may try delayed_job with a few tricks like this one. Not that great for scheduling but can use your application database.

Best current rails background task method?

I am trying to find out the best way to run scripts in the background. I have been looking around and found plenty of options, but many/most seem to have become inactive in the past few years. Let me describe my needs.
The rails app is basically a front-end to configure when and how these scripts will be run. The scripts run and generate reports and send email alerts. So the user must be able to configure the start times and how often these scripts will run dynamically. The scripts themselves should have access to the rails environment in order to save the resulting reports in the DB.
Just trying to figure out the best method from the myriad of options.
I think you're looking for a background job queuing system.
For that, you're either looking for resque or delayed_job. Both support scheduling tasks at some point in the future -- delayed_job does this natively, whereas resque has a plugin for it called resque_scheduler.
You would enqueue jobs in the background with parameters that you specify, and then at the time you selected they'll be executed. You can set jobs to recur indefinitely or a fixed number of times (at least with resque-scheduler, not sure about delayed_job).
delayed_job is easier to set up since it saves everything in the database. resque is more robust but requires you to have redis in your stack -- but if you do already it's pretty much the ideal solution for your problem.
I recently learned about Sidekiq, and I think it is really great.
There's also a RailsCast about it - Sidekiq.
Take a look at the gem whenever at https://github.com/javan/whenever.
It allows you to schedule tasks like cron jobs.
Works very well under linux, and the last commit was 14 days ago. A friend of mine used it in a project and was pretty satisfied with it.
edit: take a look at the gem delayed_job as well, it is good for executing long tasks in the background. Useful when creating a cron job only to start other tasks.

Background process in Rails 3

I am writing a Web app that will need to run a background process that will poll a web service every minute or so and then query my Rails db and send out alerts to users of the app via Twitter. I have researched this a lot but I feel I am just going around in circles. I have come across delayed_job, background_job and a few other options like creating a custom daemon suggested in a Railscast. Does anyone have any suggestions for the best way to do this? The process will have to run constantly in the background and won't be triggered by an event in the front end. Any help or guidance would be appreciated.
Why don't you just create a rake task and add it to your CRON execution?
You can even use Whenever to configure this for you.
I used Beanstalkd for this and can recommend it.
http://railscasts.com/episodes/243-beanstalkd-and-stalker
You can simply use cron for tasks that has to be executed every X minutes, hours etc.
gem whenever is usefull to setup this with rails: https://github.com/javan/whenever
I don't know much about delayed_job. But you can check out some tutorials, for example this article on heroku: http://devcenter.heroku.com/articles/delayed-job
I used delayed_job for our application.
While working on this, we researched many sites and finally we are able to apply it.
We apply our experiences in the following link
http://www.kyybaventures.com/blog/rails-delayed-job#more-2916
Hope this will help to get started with background process in rails 3.
We can either use backgroundrb or unix crontab.
Crontab will do the job if you don't want to send any heavy loaded process to run asynchronously during the request process cycle of the application.
Backgroundrb consumes lot of memory and cpu in production environment if any of the process hangs out. Also we need to configure a monitor tool to make sure that the background process is running.

Real time Alternative to polling in ruby on rails (Jruby)

I have a long running operation that I activate by placing a message on a ruby resque queue. The endpoint does the work which might take many minutes.
I was going to periodically poll the database every few second but I think the world has moved on from polling. Is there a better way using ruby on rails to get the results as a push, perhaps using something like web sockets or comet?
Can anyone suggest anything to start my research?
Websockets is the thing to research, and Pusher is a good way to get started with it.
em-websocket..or websocket-rails

Spinning Background Tasks in Rails

What is the preferred way to create a background task for a Rails application? I've heard of Starling/Workling and the good ol' script/runner, but I am curious which is becoming the defacto way to manage this need?
Thanks!
Clarification: I like the idea of Rake in Background, but the problem is, I need something that is running constantly or every 10 hours. I am not going to have the luxury of sitting on a web request, it will need to be started by the server asynchronous to the activities occurring on my site.
Ryan Bates created three great screencasts that might really help you:
Rake in Background
Starling and Workling
Custom Daemon
He talks about the various pros and cons for using each one. This should help you get started.
It depends on your needs.
Try out delayed_job, which was created by Tobi delayed_job (last updated 2011), a Shopify founder.
There are forks by DHH deleayed_job (last updated 2008), and collectiveidea delayed_job (last updated 20 days ago as of 6/28/2018).
I usually rely on cronjob scheduling as it gives the flexibility without having to write separate code to schedule it. Anything that can be executed from shell, can be scheduled! Be it any script (ruby / rake task / py / bash / any other you like), cronjob scheduling can be easily achieved.
If running on windows, one can use scheduled tasks
Hope this helps.
async_observer is the best. It doesn't do all kinds of dumb busy wait stuff or lose jobs on worker crashes like starling, no DB polling, etc... and it integrates into rails remarkably well.
I push tons of jobs through it and it pretty much doesn't care.
Most of the plugins that have been mentioned will do the job, but if all you need is a Rake task run on a set schedule, then there's really no need to start throwing more architecture at it.
Just add a cron job which executes
"cd /path/to/rails/app; RAILS_ENV=production rake run:my:task"
Why reinvent the wheel, when Unix like operating systems have been running tasks on a schedule for decades?
I have used the daemons plugin in the past.
While I don't know if it is becoming a standard, I have had great success with BackgroundRB. I have several workers, some are long running tasks triggered by a user action while others are started on a schedule.
Have a look at Taskr. It's basically like cron, but with a RESTful web interface. You can use it to schedule tasks to periodically connect to your Rails app and trigger arbitrary code (via the Taskr4rails plugin). It's meant to fit nicely into a system built around RESTful services, plus it can notify you if a task returns an error, fails to run, etc.

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