Rails deployment missing piece, filled in

http://github.com/javan/whenever/tree/master

by koops • 17 years ago

41 27 17 years ago

tjogin• 17 years ago

Very good addition to Rails, truly a missing piece as putting stuff in cronjobs spreads the logic of the app around. This makes it more readable as well.

koops2• 17 years ago

Right--whatever your session cleanup strategy is, it's got to be run from cron.

It's great that the author includes a cap task in the documentation, though the role should usually be db, not app.

teej3• 17 years ago

> whatever your session cleanup strategy is

... not really. If you're using cookie-store (the Rails default) or mem-cache-store (the fast, scalable option) there isn't any need for a session cleanup strategy.

I can definitely agree with the point on documentation - killer docs with real-life scenario examples are really key in adoption for stuff like this.

javan4• 17 years ago

I'm the author -- thanks. To keep things very clean, we created a :cron role for our deployment (which happens to be the same server as our :db). I imagine that many people are running on one server and so the :app role is fine. The point is that you can deploy different cron schedules to your various server types using roles.

stephenjudkins2• 17 years ago

Why not just use cron for this? Yes, the syntax for this does look a lot cleaner, but cron really isn't that hard to use. Why add another layer of complexity (which may break and be difficult to debug) when you could simply add lines to a crontab?

Bonus feature: "USING THE "—write-crontab" OPTION WILL COMPLETELY OVERWRITE ANY EXISTING CRONTAB ENTRIES!"

Wow. I like Ruby but many in the community's obsession with reinventing the wheel (with slightly more syntactic sugar and a hip github page) is pretty difficult for me to understand.

koops2• 17 years ago

Because if you have more than one machine running your app, you've got to reinstall the crontab everywhere. This keeps it DRY.

patio11• 17 years ago

It also means that your crontab just went in source control, which is a detail a lot of people (i.e. me) forget.

stephenjudkins2• 17 years ago

Why not just keep the crontab file in your repo? A rake task that does `cp #{project_dir}/crontab /etc/crontab` would be sufficient to meet the same needs.

javan4• 17 years ago

Whenever simply generates your crontab file for you using a cleaner syntax. It hasn't reinvented anything or added any complexity. You are just using cron.

Tichy• 17 years ago

But presumably you have to learn the new syntax?

tlrobinson• 17 years ago

Indeed, Ruby fans (I refuse to call them "Rubyists") love to talk about how Ruby is a great language for creating DSLs, which is true, but that doesn't mean you should create a new DSL for everything just because you can.

herval• 17 years ago

in this specific case, it's a bit more than 'just because you can'. Maybe it can be more like 'just because you don't want to have bugs popping around when you add new servers to your infrastructure because you forgot to setup a cronjob'

also, other languages usually offer the same kind of stuff - like Java EE's cron-like mechanisms, for instance (with or without DSLs)..

sunkencity• 17 years ago

just bite the bullet and learn to use crontab ffs.

nice sugar though...

juliend22• 17 years ago

nice, but is it possible to use it somewhere else than Rails, like say, Merb or Sinatra?

teej3• 17 years ago

Not without a little hacking. After a little digging, it looks like it has an implicit Rails dependency (http://github.com/javan/whenever/blob/f036675e94cd9dd9b21d2c...)

javan4• 17 years ago

It will work FINE without Rails. The code you're pointing to simply finds the Rails root if it exists as a convenience. If one doesn't, you have to manually tell Whenever your path: set :path, "/path/to/my/app"

jcapote• 17 years ago

I wrote something very similar to this a little while ago that's framework agnostic, http://www.github.com/jcapote/theman

juliend22• 17 years ago

cool, i didnt know about http://rufus.rubyforge.org/rufus-scheduler/ , that you're using in this project.

acangiano2• 17 years ago

Nice, but does it work on Windows?

javan4• 17 years ago

Do cron jobs work on Windows?

acangiano2• 17 years ago

No, they don't. My question asked whether yours was a convenient wrapper for cron jobs or if you implemented the same functionality in a cross-platform manner. Thanks for your answer.

Hexstream• 17 years ago

Cool. I'm in support of any syntax front-end that brings us closer to a future where everyone uses s-expressions for everything. ;P

(it's not s-expressions, but it's a step in the right direction)

fizx• 17 years ago

Lol, I wrote "RailsCron" in 2005-2006. Funny to see how the ruby community iterates.

Rails deployment missing piece, filled in

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